Battery Source [Archive] - AviationBanter

bumper

September 28th 05, 04:01 AM

Well it does limit the options, your right. However, ELK products does have
a nice little 6 volt 7.5 amp hour that could be connect in series (2) for a
12 volt 7.5 amp hour pack, or series parallel (4) for a 12 volt 15 amp hour
pack, and would fit (at least two of 'em would) as the smallest dimension is
1.34 inches. These are sealed lead acid AGM batteries - - - bumper

ELK-0675 6 Volts, 7.5 Ah
ELK Sealed Lead Acid Batteries are excellent for the following
applications with regard to size, Amp hour rating, and proper terminal
connections: battery backup (for Access Control Systems, Fire Alarm Systems,
and Security Alarm Systems), emergency lights, lighted exit signs, and
uninterruptible power supplies.

SPECIFICATIONS:
. Nominal Voltage:
. Rated Capacity:
. Length:
. Width:
. Height:
. Total Height w/ terminals:
. Weight:
. Terminals: 6 Volts
7.5 AH (20 hour rate)
5.91" (150mm)
1.34" (34mm)
3.70 (94mm)
3.90" (99mm)
3.08 lbs (1.4kg)
F1-Faston Tab No. 187

"David Kinsell" > wrote in message
. ..
> Mike the Strike wrote:
>> I am looking for a US source for a rechargeable (preferably gel or
>> sealed lead-acid) for the fin battery box of a Schempp-Hirth. I need
>> the extra power as well as the tail weight! Dimensions are
>> approximately 10 inches long, 4 inches wide and 1-1/2 inches deep.
>>
>> I've found a few single-cell solutions that I could make work but
>> wondered if there was an off-the shelf item that would fit?
>>
>> Thanks....
>>
>> Mike
>>
>
> That 1 1/2 inch depth constraint really limits your options. Feel
> fortunate if you can make up your own solution from single cells,
> or find a battery shop to do it for you.
>
> -Dave

David Kinsell

September 28th 05, 04:18 AM

> "David Kinsell" > wrote in message
> . ..
>> Mike the Strike wrote:
>>> I am looking for a US source for a rechargeable (preferably gel or
>>> sealed lead-acid) for the fin battery box of a Schempp-Hirth. I need
>>> the extra power as well as the tail weight! Dimensions are
>>> approximately 10 inches long, 4 inches wide and 1-1/2 inches deep.
>>>
>>> I've found a few single-cell solutions that I could make work but
>>> wondered if there was an off-the shelf item that would fit?
>>>
>>> Thanks....
>>>
>>> Mike
>>>
>> That 1 1/2 inch depth constraint really limits your options. Feel
>> fortunate if you can make up your own solution from single cells,
>> or find a battery shop to do it for you.
>>
>> -Dave
>
>

bumper wrote:
> Well it does limit the options, your right. However, ELK products does have
> a nice little 6 volt 7.5 amp hour that could be connect in series (2) for a
> 12 volt 7.5 amp hour pack, or series parallel (4) for a 12 volt 15 amp hour
> pack, and would fit (at least two of 'em would) as the smallest dimension is
> 1.34 inches. These are sealed lead acid AGM batteries - - - bumper
>
> ELK-0675 6 Volts, 7.5 Ah
> ELK Sealed Lead Acid Batteries are excellent for the following
> applications with regard to size, Amp hour rating, and proper terminal
> connections: battery backup (for Access Control Systems, Fire Alarm Systems,
> and Security Alarm Systems), emergency lights, lighted exit signs, and
> uninterruptible power supplies.
>
>
> SPECIFICATIONS:
> . Nominal Voltage: 6 Volts
> . Rated Capacity: 7.5 AH (20 hour rate)
> . Length: 5.91" (150mm)
> . Width: 1.34" (34mm)
> . Height: 3.70" (94mm)
> . Total Height w/ terminals: 3.90" (99mm)
> . Weight: 3.08 lbs (1.4kg)
> . Terminals: F1-Faston Tab No. 187
>
>

Top posting mistake corrected, and formatting problems fixed.
Please folks, no top posting, it screws up the readability when
you do that. Particularly when the correct bottom-posting has
been established. It's like joining a thermal in the wrong
direction, but in this case, there's only one right way to
circle.

Back to the battery. Each battery has a length of almost
6 inches, so you can't fit even two of them in the 10 inches
provided. Four would take a real trash-masher to squeeze
them in.

Plus, you'd end up with a 12 volt battery trying to power
a 14 volt radio, so you'd get about half the rated capacity
before the transmitter craps out. But that's a little
too technical for this crowd.

-Dave

Eric Greenwell

September 28th 05, 05:28 AM

David Kinsell wrote:
>
>> "David Kinsell" > wrote in message
>> . ..
>>
>>> Mike the Strike wrote:
>>>
>>>> I am looking for a US source for a rechargeable (preferably gel or
>>>> sealed lead-acid) for the fin battery box of a Schempp-Hirth. I need
>>>> the extra power as well as the tail weight! Dimensions are
>>>> approximately 10 inches long, 4 inches wide and 1-1/2 inches deep.
>>>>
>>>> I've found a few single-cell solutions that I could make work but
>>>> wondered if there was an off-the shelf item that would fit?
>>>>
>>>> Thanks....
>>>>
>>>> Mike
>>>>
>>> That 1 1/2 inch depth constraint really limits your options. Feel
>>> fortunate if you can make up your own solution from single cells,
>>> or find a battery shop to do it for you.
>>>
>>> -Dave
>>
>>
>>
>
> bumper wrote:
> > Well it does limit the options, your right. However, ELK products
> does have
> > a nice little 6 volt 7.5 amp hour that could be connect in series (2)
> for a
> > 12 volt 7.5 amp hour pack, or series parallel (4) for a 12 volt 15
> amp hour
> > pack, and would fit (at least two of 'em would) as the smallest
> dimension is
> > 1.34 inches. These are sealed lead acid AGM batteries - - - bumper
> >
> > ELK-0675 6 Volts, 7.5 Ah
> > ELK Sealed Lead Acid Batteries are excellent for the
> following
> > applications with regard to size, Amp hour rating, and proper terminal
> > connections: battery backup (for Access Control Systems, Fire Alarm
> Systems,
> > and Security Alarm Systems), emergency lights, lighted exit signs, and
> > uninterruptible power supplies.
> >
> >
> > SPECIFICATIONS:
> > . Nominal Voltage: 6 Volts
> > . Rated Capacity: 7.5 AH (20 hour rate)
> > . Length: 5.91" (150mm)
> > . Width: 1.34" (34mm)
> > . Height: 3.70" (94mm)
> > . Total Height w/ terminals: 3.90" (99mm)
> > . Weight: 3.08 lbs (1.4kg)
> > . Terminals: F1-Faston Tab No. 187
> >
> >
>
>
> Top posting mistake corrected,

I'd call it a preference instead of a mistake, but I also prefer bottom
posting.

> and formatting problems fixed.
> Please folks, no top posting, it screws up the readability when
> you do that. Particularly when the correct bottom-posting has
> been established. It's like joining a thermal in the wrong
> direction, but in this case, there's only one right way to
> circle.
>
> Back to the battery. Each battery has a length of almost
> 6 inches, so you can't fit even two of them in the 10 inches
> provided. Four would take a real trash-masher to squeeze
> them in.
>
> Plus, you'd end up with a 12 volt battery trying to power
> a 14 volt radio, so you'd get about half the rated capacity
> before the transmitter craps out. But that's a little
> too technical for this crowd.

Now, now, Dave, Mike didn't indicate it was for a 14 volt radio, or even
that it was for a radio at all. Maybe it's to back up his logger and
vario. And, 14 volts might not be compatible with his other battery(s).
Before prescribing solutions, the volt doctor should determine the problem!

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

David Kinsell

September 28th 05, 06:30 AM

Eric Greenwell wrote:
> David Kinsell wrote:
>>
>>> "David Kinsell" > wrote in message
>>> . ..
>>>
>>>> Mike the Strike wrote:
>>>>
>>>>> I am looking for a US source for a rechargeable (preferably gel or
>>>>> sealed lead-acid) for the fin battery box of a Schempp-Hirth. I need
>>>>> the extra power as well as the tail weight! Dimensions are
>>>>> approximately 10 inches long, 4 inches wide and 1-1/2 inches deep.
>>>>>
>>>>> I've found a few single-cell solutions that I could make work but
>>>>> wondered if there was an off-the shelf item that would fit?
>>>>>
>>>>> Thanks....
>>>>>
>>>>> Mike
>>>>>
>>>> That 1 1/2 inch depth constraint really limits your options. Feel
>>>> fortunate if you can make up your own solution from single cells,
>>>> or find a battery shop to do it for you.
>>>>
>>>> -Dave
>>>
>>>
>>>
>>
>> bumper wrote:
>> > Well it does limit the options, your right. However, ELK
>> > products does have a nice little 6 volt 7.5 amp hour that
>> > could be connect in series (2) for a 12 volt 7.5 amp hour
>> > pack, or series parallel (4) for a 12 volt 15 amp hour
>> > pack, and would fit (at least two of 'em would) as the
>> > smallest dimension is 1.34 inches. These are sealed lead
>> > acid AGM batteries - - - bumper
>> >
>> > ELK-0675 6 Volts, 7.5 Ah
>> > ELK Sealed Lead Acid Batteries are excellent for the
>> > following applications with regard to size, Amp hour rating, and
>> > proper terminal connections: battery backup (for Access Control
>> > Systems, Fire AlarmSystems, and Security Alarm Systems), emergency
>> > lights, lighted exitsigns, and uninterruptible power supplies.
>> >
>> >
>> > SPECIFICATIONS:
>> > . Nominal Voltage: 6 Volts
>> > . Rated Capacity: 7.5 AH (20 hour rate)
>> > . Length: 5.91" (150mm)
>> > . Width: 1.34" (34mm)
>> > . Height: 3.70" (94mm)
>> > . Total Height w/ terminals: 3.90" (99mm)
>> > . Weight: 3.08 lbs (1.4kg)
>> > . Terminals: F1-Faston Tab No. 187
>> >
>> >
>>
>>
>> Top posting mistake corrected,
>
> I'd call it a preference instead of a mistake, but I also prefer bottom
> posting.
>

Doing top-posting after bottom posting had been initiated in a string is
a mistake by any reasonable definition.

A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What's the most annoying thing on Usenet and in email?

http://www.caliburn.nl/topposting.html

>> and formatting problems fixed.
>> Please folks, no top posting, it screws up the readability when
>> you do that. Particularly when the correct bottom-posting has
>> been established. It's like joining a thermal in the wrong
>> direction, but in this case, there's only one right way to
>> circle.
>>
>> Back to the battery. Each battery has a length of almost
>> 6 inches, so you can't fit even two of them in the 10 inches
>> provided. Four would take a real trash-masher to squeeze
>> them in.
>>
>> Plus, you'd end up with a 12 volt battery trying to power
>> a 14 volt radio, so you'd get about half the rated capacity
>> before the transmitter craps out. But that's a little
>> too technical for this crowd.
>
> Now, now, Dave, Mike didn't indicate it was for a 14 volt radio, or even
> that it was for a radio at all.

And what radio do you suppose he's using if it's not a 14 volt radio?

> Maybe it's to back up his logger and
> vario.

Both of which would work better on 14 volts. You do know it's been
the standard for small aircraft electrical systems for what, 50,
75 years now?? A bunch of cheap-ass glider pilots aren't about to
change that fact, are they?

> And, 14 volts might not be compatible with his other battery(s).

You don't think he's going to actually hook the batteries together
do you? That would blow the tail clean off the glider, if you believe
what you read in RAS!!

> Before prescribing solutions, the volt doctor should determine the problem!

It's not real hard to divine the problem with most electrical systems.
Not enough volts, too many pounds of dead weight in improper batteries.
Not a hard diagnosis at all.

-Dave

Mike the Strike

September 28th 05, 07:01 AM

Thanks for all the suggestions. Actually, I've used 12-volt batteries
in all my gliders and never had a problem. This 12/14 V argument is
really unnecessary! Good German instruments like the Becker and Dittel
radios are quite happy with a 12-volt supply.

The solution to my problem is a two-pack of 6V 7 Ah batteries which fit
the space quite nicely.

David Kinsell

September 29th 05, 01:50 PM

Mike the Strike wrote:
> Thanks for all the suggestions. Actually, I've used 12-volt batteries
> in all my gliders and never had a problem. This 12/14 V argument is
> really unnecessary! Good German instruments like the Becker and Dittel
> radios are quite happy with a 12-volt supply.

Happy?? With a fresh battery, they work for a while, but die after only
part of the rated capacity is used up. Understanding such a complex
issue is way beyond the comprehension of most glider pilots, apparently.

If your current batteries were working so well, I don't suppose you'd be
needing to add yet another one. Seems like the people who run 12 volts
are the ones always looking to find somewhere to cram more batteries
into their glider. Gee, I wonder why??

Paul Remde

September 29th 05, 02:22 PM

Hi David,

You crack me up.

I highly recommend 12V systems in gliders. You can save yourself a lot of
money and hassle by using 12V batteries.

The design of radios has changed a lot in recent years. Good radios don't
require 14V batteries. Low cost and old radios do prefer 14V power.

Good Soaring,

Paul Remde

"David Kinsell" > wrote in message
...
> Mike the Strike wrote:
>> Thanks for all the suggestions. Actually, I've used 12-volt batteries
>> in all my gliders and never had a problem. This 12/14 V argument is
>> really unnecessary! Good German instruments like the Becker and Dittel
>> radios are quite happy with a 12-volt supply.
>
> Happy?? With a fresh battery, they work for a while, but die after only
> part of the rated capacity is used up. Understanding such a complex
> issue is way beyond the comprehension of most glider pilots, apparently.
>
> If your current batteries were working so well, I don't suppose you'd be
> needing to add yet another one. Seems like the people who run 12 volts
> are the ones always looking to find somewhere to cram more batteries
> into their glider. Gee, I wonder why??
>
>

[email protected]

September 29th 05, 03:57 PM

David Kinsell wrote:
> Happy?? With a fresh battery, they work for a while, but die after only
> part of the rated capacity is used up. Understanding such a complex
> issue is way beyond the comprehension of most glider pilots, apparently.

Dave,

I prefer 14 volt batteries and used them for many years. But I've used
12 volts in my ASW 24 for nearly 14 years with no problems. Currently
(no pun intended), I'm running a Dittel radio, LNAV, GPS-NAV, and
Compaq Aero 1550 with a common 7 amp-hour sealed lead-acid cell. If I
add a transponder, I'll be looking to add a battery but until then I'm
OK. The second battery in the vertical fin (i.e., what Mike is seeking)
is a backup that I've only used a few times when my primary battery was
failing (as in: I had to buy a new one). I've had experts tell me
(somewhat more politely) that 14 volts doesn't really buy me much
unless I increase the amp-hour capacity of the battery pack. My
response was always that radio transmitters start to perform badly
below about 11 volts even if everything else works OK down to, say, 9v,
so 14 volts gives me a little more transmit time (and I think that's
what your point is). The battery box in my '24 holds a 12v cell nicely,
however, so that's what I use. I saw a slightly taller 12v battery with
significantly more amp-hours recently that would also fit but haven't
heard whether it's real or just marketing hype. [Larry, were you going
to report on the PowerSonic PSH-12100 10.5 AH battery?]

Speaking of preferences, so is top (or bottom) posting. I agree that
bottom posting (i.e., adding one's response after the quoted text from
the previous author's posting rather than before) is a recommended
convention. But top posting isn't on my personal list of "most annoying
things on the Usenet." A lot of folks (including me) use Google Groups
to read newsgroups so top posting works fine: quoted text is [mostly]
suppressed anyway so each posting follows the previous one and
preserves the order in which people read them. If I'm responding
point-by-point, I'll bottom post or interleave quoted text with
responses but it's situational. And strictly a preference, not a
requirement.

Perhaps at the top of my own list of most annoying things on the Usenet
is people who insult or belittle readers in an attempt to advance their
own views. I'm being harsh on you because you've made a number of
excellent contributions to this group in the past. Apparently this
thread hit a couple of sensitive points. If I may offer a suggestion,
it's that readers still tend to weigh the merits of what one says with
less regard for the vehemence with which it's expressed.

So in an agitated exchange, the message survives. What suffers is one's
reputation for civility. I'd be unhappy to see this occur to any of the
valued and knowledgeable contributors to this group.

Chip Bearden

[email protected]

September 29th 05, 03:58 PM

Robert Backer

September 29th 05, 04:46 PM

I am very pleased with the powersonic 8.5 ah battery which is exactly
the same size as the typical 7 ah battery. Running a 302, Ipaq, becker
3201 radio and becker transponder (with encoder) and on flights of up to
6 hours have yet to switch to the backup battery.

Bob

wrote:
> David Kinsell wrote:
>
>>Happy?? With a fresh battery, they work for a while, but die after only
>>part of the rated capacity is used up. Understanding such a complex
>>issue is way beyond the comprehension of most glider pilots, apparently.
>
>
> Dave,
>
> I prefer 14 volt batteries and used them for many years. But I've used
> 12 volts in my ASW 24 for nearly 14 years with no problems. Currently
> (no pun intended), I'm running a Dittel radio, LNAV, GPS-NAV, and
> Compaq Aero 1550 with a common 7 amp-hour sealed lead-acid cell. If I
> add a transponder, I'll be looking to add a battery but until then I'm
> OK. The second battery in the vertical fin (i.e., what Mike is seeking)
> is a backup that I've only used a few times when my primary battery was
> failing (as in: I had to buy a new one). I've had experts tell me
> (somewhat more politely) that 14 volts doesn't really buy me much
> unless I increase the amp-hour capacity of the battery pack. My
> response was always that radio transmitters start to perform badly
> below about 11 volts even if everything else works OK down to, say, 9v,
> so 14 volts gives me a little more transmit time (and I think that's
> what your point is). The battery box in my '24 holds a 12v cell nicely,
> however, so that's what I use. I saw a slightly taller 12v battery with
> significantly more amp-hours recently that would also fit but haven't
> heard whether it's real or just marketing hype. [Larry, were you going
> to report on the PowerSonic PSH-12100 10.5 AH battery?]
>
> Speaking of preferences, so is top (or bottom) posting. I agree that
> bottom posting (i.e., adding one's response after the quoted text from
> the previous author's posting rather than before) is a recommended
> convention. But top posting isn't on my personal list of "most annoying
> things on the Usenet." A lot of folks (including me) use Google Groups
> to read newsgroups so top posting works fine: quoted text is [mostly]
> suppressed anyway so each posting follows the previous one and
> preserves the order in which people read them. If I'm responding
> point-by-point, I'll bottom post or interleave quoted text with
> responses but it's situational. And strictly a preference, not a
> requirement.
>
> Perhaps at the top of my own list of most annoying things on the Usenet
> is people who insult or belittle readers in an attempt to advance their
> own views. I'm being harsh on you because you've made a number of
> excellent contributions to this group in the past. Apparently this
> thread hit a couple of sensitive points. If I may offer a suggestion,
> it's that readers still tend to weigh the merits of what one says with
> less regard for the vehemence with which it's expressed.
>
> So in an agitated exchange, the message survives. What suffers is one's
> reputation for civility. I'd be unhappy to see this occur to any of the
> valued and knowledgeable contributors to this group.
>
> Chip Bearden
>

01-- Zero One

September 29th 05, 04:46 PM

" > wrote in message
ups.com:

> David Kinsell wrote:
> > Happy?? With a fresh battery, they work for a while, but die after only
> > part of the rated capacity is used up. Understanding such a complex
> > issue is way beyond the comprehension of most glider pilots, apparently.
>
> Dave,
>
> I prefer 14 volt batteries and used them for many years. But I've used
> 12 volts in my ASW 24 for nearly 14 years with no problems. Currently
> (no pun intended), I'm running a Dittel radio, LNAV, GPS-NAV, and
> Compaq Aero 1550 with a common 7 amp-hour sealed lead-acid cell. If I
> add a transponder, I'll be looking to add a battery but until then I'm
> OK. The second battery in the vertical fin (i.e., what Mike is seeking)
> is a backup that I've only used a few times when my primary battery was
> failing (as in: I had to buy a new one). I've had experts tell me
> (somewhat more politely) that 14 volts doesn't really buy me much
> unless I increase the amp-hour capacity of the battery pack. My
> response was always that radio transmitters start to perform badly
> below about 11 volts even if everything else works OK down to, say, 9v,
> so 14 volts gives me a little more transmit time (and I think that's
> what your point is). The battery box in my '24 holds a 12v cell nicely,
> however, so that's what I use. I saw a slightly taller 12v battery with
> significantly more amp-hours recently that would also fit but haven't
> heard whether it's real or just marketing hype. [Larry, were you going
> to report on the PowerSonic PSH-12100 10.5 AH battery?]
>

Chip,

I bought and installed a couple of these before Uvalde. Have not had a
chance to 'characterize' them but they certainly lasted a lot longer
than the previous (admittedly older) smaller batteries.

So far, I am pleased.

Larry

Papa3

September 29th 05, 05:15 PM

Paul Remde wrote:
> Hi David,
>
> I highly recommend 12V systems in gliders. You can save yourself a lot of
> money and hassle by using 12V batteries.
>
> The design of radios has changed a lot in recent years. Good radios don't
> require 14V batteries. Low cost and old radios do prefer 14V power.
>
> Good Soaring,
>
> Paul Remde
>

Mike et. al.

I used to be a "14 volter", using the old Gates Cells and later Sealed
Lead Acid. My new ship has all modern electronics (LNav, GPSNav,
Becker), and I have absolutely no issues running 12 Volts. I've
primarily used the Powersonic PSH-12100 (12V, 12AH) with good success.
I can easily get in a full weekend of flying (8-10hrs) on a single
charge. With reasonable care (storing in a cool, dry environment,
recharging after flying), they seem to last about 3-4 seasons (probably
about 150-200 cycles with my flying schedule). If you look at the
discharge charts, there's not a huge difference in useful time at our
typical discharge rates (on average less than 1 amp draw) between the
12AH and 10AH models, but it's only a couple of bucks more to buy the
higher capacity battery.

None of which, I guess, answers your original question.... The largest
capacity Powersonic that fits your specs is the PS-1229, which is only
2.9AH and 2.2lbs. Sufficient as a "get home" backup if you turn off
the radio but not what you'd want to run for a whole day of flying.
Also, in this case, there is some need to consider voltage drop across
the long wire you will have running back to the tail. You can make up
a 14 Volt kit by attaching an additional 2V 6AH cell that they have,
though in general they recommend matching the load ratings more
closely.

P3

Paul M. Cordell

September 29th 05, 07:07 PM

David Kinsell wrote:
> Mike the Strike wrote:
>
>> Thanks for all the suggestions. Actually, I've used 12-volt batteries
>> in all my gliders and never had a problem. This 12/14 V argument is
>> really unnecessary! Good German instruments like the Becker and Dittel
>> radios are quite happy with a 12-volt supply.
>
>
> Happy?? With a fresh battery, they work for a while, but die after only
> part of the rated capacity is used up. Understanding such a complex
> issue is way beyond the comprehension of most glider pilots, apparently.
>
> If your current batteries were working so well, I don't suppose you'd be
> needing to add yet another one. Seems like the people who run 12 volts
> are the ones always looking to find somewhere to cram more batteries
> into their glider. Gee, I wonder why??
>
>
This response is worth replying to....Mike the Strike.....AKA a Chief
Scientist (PHD) in a consulting company specializing in Power Quality
and Electromagnetic Environment It’s my guess that he understands the
“Complex” issues involved in sailplane electrical systems.

Eric Greenwell

September 29th 05, 07:42 PM

David Kinsell wrote:

> Happy?? With a fresh battery, they work for a while, but die after only
> part of the rated capacity is used up. Understanding such a complex
> issue is way beyond the comprehension of most glider pilots, apparently.

But not this one - electrical engineer for 33 years.

> If your current batteries were working so well, I don't suppose you'd be
> needing to add yet another one. Seems like the people who run 12 volts
> are the ones always looking to find somewhere to cram more batteries
> into their glider. Gee, I wonder why??

Maybe this will clear it up: they've added an Ipaq (250-500 ma), a
logger (100-200 ma), another vario (50-100 ma), a transponder (450-650
ma), a TPAS (50 ma?). Or they screwed up, left a switch on overnight,
ran the battery down, and decided they needed a backup. Or it's simply
inconvenient to charge everyday. Or they are obsessive. Or they needed
tail weight, and thought the lead back there might just as well be doing
something useful in a battery instead of just sitting there.

And since most glider pilots are using 12 volts, it isn't so strange
they are the ones we hear from. Also, it's my observation that the
gliders with the older radios and 14 volt battery, besides being a
smaller number each year as these radios die, simply aren't getting the
new equipment I've listed. They typically belong to a club or local
flyer that has no need for more equipment.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Mike the Strike

September 29th 05, 08:06 PM

David:

Complex?

Modern glider instruments (including radios) are designed to operate on
a nominal 12 V supply. My Dittel FSG-71 gives the voltage range as
13.8 V+ 10% -20%, which translates into 11 V to 15 V. My SN-10
specifies 10 V to 15 V.

A fully-charged lead-acid or gel has a voltage somewhere in the 12.5 V
range and drops to around 11.5 V as it is discharged to 50% of its
capacity. A voltage of 11 V or below means the battery is pretty much
dead - either old or over-drained. (Standard data gives final cell
voltage of 1.83 V for a moderately slowly-drained battery at normal
temperatures, but it could be lower).

Many low-voltage indication problems are not just battery issues but
wiring problems - thin wiring, corroded connectors with high-resistance
joints. (being such a smart guy, you're no doubt familiar with Ohm's
Law)

Of course, a 14 V battery will give you a bit more power and enable you
to run the batteries down further, but the tradeoff is usually a
cobbled-together non-standard battery stack that you can't charge with
an off-the-shelf charger.

In my Discus, my added batteries are nothing to do with lack of
performance of the existing system which is flawless, but I am adding a
power-hungry transponder. I am reconfiguring the batteries accordingly
and adding a fin battery as backup for my main panel instruments. I
need 6 pounds of weight in the tail anyway, so it makes more sense to
put a useful lead battery there than just dead weight.

Please keep your comments civil.

Andy

September 29th 05, 09:05 PM

It's probably also worth noting that a 14volt pack hot off the charger
has a terminal voltage greater than 15 volts and will exceed the
maximum voltage specs for many modern glider systems.

Andy

Udo Rumpf

September 29th 05, 09:42 PM

"T o d d P a t t i s t" wrote:
>
>>Of course, a 14 V battery will give you a bit more power and enable you
>>to run the batteries down further, but the tradeoff is usually a
>>cobbled-together non-standard battery stack that you can't charge with
>>an off-the-shelf charger.
>
> I've run 12 volts and I've run 14 volts. The charger
> comment above is the main disadvantage of 14 volts. The
> secondary disadvantage is the "non-standard battery stack"
> may not want to fit into your standard-sized battery
> location.
>
> An advantage to 14 volt is more radio power/longer range on
> transmit. Modern radios don't cut out at lower voltage, like
> older radios that assumed 13.8 volts, but they all drive the
> output stages off the full voltage - the more voltage, the
> more output power.
>
> Other advantages are that you can run the battery longer
> before it gets too low, and for any switchmode DC-DC
> downconverters, such as I use for my IPAQ's 5 volt
> requirements, you get less current draw and the battery
> lasts longer (which it should since you've got more stored
> energy). For me, the advantages of 14 volts outweigh the
> disadvantages on my primary battery (it fits into the space
> available), but not for my backup battery (the larger 14
> volt battery won't fit there.)
>
> It ultimately comes down to preference.

I agree with above.
I fly with a Dittle Radio.
If the radio is on but I do not talk, my 7AH 12V battery lasts
about 4.5 hour with the usual LNav, logger and 1530 Ipaq.
The battery will read about 11.8 volts after that time. At that
point if I make a call on the radio the chances are I will not be
heard unless I am close to the field. That is due in large part
the hand held radios seem not to do very well when it comes
to receiving a call from a radio with lower battery power. I have
made it a habit of switching to the reserve battery for my final
glide and use this battery again the next day while I charge
up the other one over night. I had an experience recently
whereby heaved in the cockpit. I tried to make a call, that I
would land in about 1/2 hour. I needed a bucket of hot water
and clean closing. I was not received as I forgot to switch the
battery. Lucky for me my call was being relayed and my wife
was ready with the goods.
Regards
Udo

Eric Greenwell

September 30th 05, 03:57 AM

Udo Rumpf wrote:

> I fly with a Dittle Radio.
> If the radio is on but I do not talk, my 7AH 12V battery lasts about 4.5
> hour with the usual LNav, logger and 1530 Ipaq. The battery will read
> about 11.8 volts after that time. At that point if I make a call on the
> radio the chances are I will not be heard unless I am close to the
> field. That is due in large part the hand held radios seem not to do
> very well when it comes to receiving a call from a radio with lower
> battery power.

You didn't say which Dittel, but the brochure for the one I looked (FSG
2T) indicated plenty of power (>5 watts) at 11 volts. Perhaps yours is
an older model, but even @ 2 watts (like the Becker 4201 and Microair),
the range would drop off only about 40% compared the nominal 5 watts at
13.75 volts.

It's possible you have a problem not related to the voltage; e.g., maybe
the voltage is dropping well below the 11.8 volts when the transmitter
is keyed, or the radio is not functioning within specifications.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

David Kinsell

September 30th 05, 01:23 PM

Paul Remde wrote:
> Hi David,
>
> You crack me up.
>
> I highly recommend 12V systems in gliders. You can save yourself a lot of
> money and hassle by using 12V batteries.

You want me to be like Mike/Strike and put in multiple 12 volt batteries
in hopes of getting enough juice to run a panel? After a while, he'll
figure out that switching batteries glitches his FR, computer, and radio,
so he starts throwing in the monster capacitors, the power Shottkies,
the microprocessor-controlled reed relays, and all the other garbage people
use to try to get around the problems. Seems like when people try to be
cheap and lazy, it ends up costing them time and money in the long run.
It's one of those false economies type of things.

My little 14 volt tail battery (singular) powers the panel just fine even
after being cold-soaked at 18 grand for 5 hours. In fact, at the end of
the flight, it delivers more juice to the panel than people flying around
with 20 A-H of batteries have at take off. Been running a FR for about
six years, and haven't had a single glitch in the data in all that time.
If you have some actual information about why running undervoltage batteries
is such a great idea, I'd like to hear it, but you really haven't offered
anything but personal opinion with no facts to back it up.

>
> The design of radios has changed a lot in recent years. Good radios don't
> require 14V batteries. Low cost and old radios do prefer 14V power.
>

Really? You need to immediately contact the German manufacturers and share
your revelations with them. Since you know more about the radios than they
do, they'll be happy to correct all the wrong information in their manuals.
If you should happen to actually read the manuals, you'll see they all
have nominal input voltages of 13.8 volts, just like always, but since
you're so much smarter than they are, you can rewrite the manuals for them.
Obviously, they all have no idea what they're talking about, since they're
only the ones who designed the radios.

Dave

Udo Rumpf

September 30th 05, 02:12 PM

>> I fly with a Dittle Radio.
>> If the radio is on but I do not talk, my 7AH 12V battery lasts about 4.5
>> hour with the usual LNav, logger and 1530 Ipaq. The battery will read
>> about 11.8 volts after that time. At that point if I make a call on the
>> radio the chances are I will not be heard unless I am close to the field.
>> That is due in large part the hand held radios seem not to do very well
>> when it comes to receiving a call from a radio with lower battery power.

>
> You didn't say which Dittel, but the brochure for the one I looked (FSG
> 2T) indicated plenty of power (>5 watts) at 11 volts. Perhaps yours is an
> older model, but even @ 2 watts (like the Becker 4201 and Microair), the
> range would drop off only about 40% compared the nominal 5 watts at 13.75
> volts.
>
> It's possible you have a problem not related to the voltage; e.g., maybe
> the voltage is dropping well below the 11.8 volts when the transmitter is
> keyed, or the radio is not functioning within specifications.

>
> Eric Greenwell

I have a 720A Dittle radio
Power requirements;
Receive .1 - .4 amps
Transmit (tone) 1.4 amps (.8 amps unmodulated)
The 11.8 volts I was referring to is before transmit.
If I remember correctly when the battery is fully charged
and I hit the transmit button the voltage drops from 12.7 to 12.2.
Udo

Bert Willing

September 30th 05, 02:18 PM

I'm flying with a 12V/12Ah battery with a full panel (calculator, radio,
Colibri, Ipaq, FLARM), and after 10h of operation the battery shows still
12.4V with the radio transmitting.

So what exactly do you need the 14V for?

--
Bert Willing

ASW20 "TW"

"David Kinsell" > a écrit dans le message de news:
...
> Paul Remde wrote:
>> Hi David,
>>
>> You crack me up.
>>
>> I highly recommend 12V systems in gliders. You can save yourself a lot of
>> money and hassle by using 12V batteries.
>
> You want me to be like Mike/Strike and put in multiple 12 volt batteries
> in hopes of getting enough juice to run a panel? After a while, he'll
> figure out that switching batteries glitches his FR, computer, and radio,
> so he starts throwing in the monster capacitors, the power Shottkies,
> the microprocessor-controlled reed relays, and all the other garbage
> people
> use to try to get around the problems. Seems like when people try to be
> cheap and lazy, it ends up costing them time and money in the long run.
> It's one of those false economies type of things.
>
> My little 14 volt tail battery (singular) powers the panel just fine even
> after being cold-soaked at 18 grand for 5 hours. In fact, at the end of
> the flight, it delivers more juice to the panel than people flying around
> with 20 A-H of batteries have at take off. Been running a FR for about
> six years, and haven't had a single glitch in the data in all that time.
> If you have some actual information about why running undervoltage
> batteries
> is such a great idea, I'd like to hear it, but you really haven't offered
> anything but personal opinion with no facts to back it up.
>
>>
>> The design of radios has changed a lot in recent years. Good radios
>> don't require 14V batteries. Low cost and old radios do prefer 14V
>> power.
>>
>
> Really? You need to immediately contact the German manufacturers and
> share
> your revelations with them. Since you know more about the radios than
> they
> do, they'll be happy to correct all the wrong information in their
> manuals.
> If you should happen to actually read the manuals, you'll see they all
> have nominal input voltages of 13.8 volts, just like always, but since
> you're so much smarter than they are, you can rewrite the manuals for
> them.
> Obviously, they all have no idea what they're talking about, since they're
> only the ones who designed the radios.
>
> Dave
>
>

John Wilton

September 30th 05, 02:20 PM

"David Kinsell" > wrote in message
...
> Paul Remde wrote:
>> Hi David,
>>
>> You crack me up.
>>
>> I highly recommend 12V systems in gliders. You can save yourself a lot of
>> money and hassle by using 12V batteries.
>
> You want me to be like Mike/Strike and put in multiple 12 volt batteries
> in hopes of getting enough juice to run a panel? After a while, he'll
> figure out that switching batteries glitches his FR, computer, and radio,
> so he starts throwing in the monster capacitors, the power Shottkies,
> the microprocessor-controlled reed relays, and all the other garbage
> people
> use to try to get around the problems. Seems like when people try to be
> cheap and lazy, it ends up costing them time and money in the long run.
> It's one of those false economies type of things.
>
> My little 14 volt tail battery (singular) powers the panel just fine even
> after being cold-soaked at 18 grand for 5 hours. In fact, at the end of
> the flight, it delivers more juice to the panel than people flying around
> with 20 A-H of batteries have at take off. Been running a FR for about
> six years, and haven't had a single glitch in the data in all that time.
> If you have some actual information about why running undervoltage
> batteries
> is such a great idea, I'd like to hear it, but you really haven't offered
> anything but personal opinion with no facts to back it up.
>
>>
>> The design of radios has changed a lot in recent years. Good radios
>> don't require 14V batteries. Low cost and old radios do prefer 14V
>> power.
>>
>
> Really? You need to immediately contact the German manufacturers and
> share
> your revelations with them. Since you know more about the radios than
> they
> do, they'll be happy to correct all the wrong information in their
> manuals.
> If you should happen to actually read the manuals, you'll see they all
> have nominal input voltages of 13.8 volts, just like always, but since
> you're so much smarter than they are, you can rewrite the manuals for
> them.
> Obviously, they all have no idea what they're talking about, since they're
> only the ones who designed the radios.
>
> Dave
>
>

I don't have a manual for my Becker AR3201 so I had a look on the
manufacturer's website for the current equivalent model and found this:

http://www.becker-avionics.com/product/files/ar4201.pdf

The top of page 2 states:
Supply Voltage: 12.4 - 15.1 V
Emergency Supply Voltage: 10.0 V

I am now confused ! Please can you explain what you mean by nominal input
voltage - is that the average of the maximum and the minimum ? Any idea
what is meant by Emergency Supply Voltage?

Regards,
John Wilton

[email protected]

September 30th 05, 02:21 PM

Eric Greenwell wrote:
> It's possible you have a problem not related to the voltage; e.g., maybe
> the voltage is dropping well below the 11.8 volts when the transmitter
> is keyed, or the radio is not functioning within specifications.

Many of us use the LNAV battery voltage screen to check batteries (I
assume the CAI 302 and other vario/flight computers offer the same
thing). That seems to be pretty accurate and has the advantage of
reading the voltage at the instrument where it counts, not at the
battery before current must traverse small diameter wiring, corroded
connectors, etc., with subsequent loss in voltage.

BUT...one must key the radio mike and hold it down for several seconds
(don't everyone do this at once on the local glider frequency) to get
an updated reading for the voltage under full transmit load. That's
nearly always lower. I've never checked to see whether the LNAV readout
takes a while to register the new voltage or whether the battery
actually sags after several seconds under load. I'm not sure it matters
since few pilots seem to be able to limit their tranmissions to less
than 5 seconds, though. :)

Chip Bearden

Paul Remde

September 30th 05, 02:30 PM

Hi David,

I think your observations are interesting.

One part that is interesting is that you talk about how so many pilots that
use 12V systems are having problems. I have heard from both 12V and 14V
advocates that have problems with their batteries. Like you, I have never
had any problems with my batteries. I use 12V batteries.

I think that the majority of "battery problems" are owner induced. It is
difficult to remember when you purchased a battery. Most people naturally
underestimate the age of their batteries. I think many pilots are flying
with old batteries that have not been cared for and then they complain about
them.

I take care of my batteries. I don't let them sit for more than 3 months
without recharging, I charge them before flying, I replace them every 2
years. Every time I get a new battery I put the date on it so that I will
know when to replace it. I don't want a battery failure during a record
flight or contest flight - or any flight for that matter.

I stock a lot of Power-Sonic batteries for sale to glider pilots. My
calendar reminds me to charge them every 3 months so they will not be
damaged.

Many pilots fly with 12V systems and we really are very happy with them.
People can hear our radio transmissions from very far away and we are heard
clearly. People who take care of their 14V systems will also have good
results. They may truly have a few more watts of transmit power. To me the
issues involved with 14V systems are not worth the extra small percentage of
transmit power. Many glider pilots agree with me that 12V systems are
great. Many glider pilots prefer 14V systems. I think it will always be
that way.

Issues with 14V systems.
- Most glider battery compartments are designed to hold 12V batteries so it
is difficult to secure a 14V battery well. Radio manufacturers make
extremely rugged and easy to use battery boxes for 12V batteries, but 14V
batteries don't fit into them.
- It is difficult to match 12V and 2V batteries well so that they charge
equally. I have tried running 14V systems in my gliders in the past. I
found that the 2V battery was completely dead at the end of every soaring
season. That is the main reason I switched to 12V systems.
- 14V chargers are more difficult to find and more expensive. After you
invest in one and later come to the conclusions that many of us have (that
12V systems are fine) you will throw away your expensive 14V charger and
invest in a 12V charger.

I find your comment about German radio manufacturers to be funny. They all
sell 12V batteries and battery boxes. So they are endorsing the use of 12V
batteries. They must agree with me (and many other glider pilots) that 12V
systems are acceptable and, dare I say it... preferable.

Uh Oh... I just top posted! (my preference)

Good Soaring,

Paul Remde

"David Kinsell" > wrote in message
...
> Paul Remde wrote:
>> Hi David,
>>
>> You crack me up.
>>
>> I highly recommend 12V systems in gliders. You can save yourself a lot of
>> money and hassle by using 12V batteries.
>
> You want me to be like Mike/Strike and put in multiple 12 volt batteries
> in hopes of getting enough juice to run a panel? After a while, he'll
> figure out that switching batteries glitches his FR, computer, and radio,
> so he starts throwing in the monster capacitors, the power Shottkies,
> the microprocessor-controlled reed relays, and all the other garbage
> people
> use to try to get around the problems. Seems like when people try to be
> cheap and lazy, it ends up costing them time and money in the long run.
> It's one of those false economies type of things.
>
> My little 14 volt tail battery (singular) powers the panel just fine even
> after being cold-soaked at 18 grand for 5 hours. In fact, at the end of
> the flight, it delivers more juice to the panel than people flying around
> with 20 A-H of batteries have at take off. Been running a FR for about
> six years, and haven't had a single glitch in the data in all that time.
> If you have some actual information about why running undervoltage
> batteries
> is such a great idea, I'd like to hear it, but you really haven't offered
> anything but personal opinion with no facts to back it up.
>
>>
>> The design of radios has changed a lot in recent years. Good radios
>> don't require 14V batteries. Low cost and old radios do prefer 14V
>> power.
>>
>
> Really? You need to immediately contact the German manufacturers and
> share
> your revelations with them. Since you know more about the radios than
> they
> do, they'll be happy to correct all the wrong information in their
> manuals.
> If you should happen to actually read the manuals, you'll see they all
> have nominal input voltages of 13.8 volts, just like always, but since
> you're so much smarter than they are, you can rewrite the manuals for
> them.
> Obviously, they all have no idea what they're talking about, since they're
> only the ones who designed the radios.
>
> Dave
>
>

Tim Mara

September 30th 05, 03:57 PM

What "Dittel" Radio?
I hear this very commonly that "I have a Dittel" radio.....and I'm sure most
people "assume" (and we all know what that means) that a "Dittel" radio is a
"Walter Dittel" radio .....If it's an ATR (Dittel) of any kind then it is an
"AVIONIC DITTEL" which is far from the "WALTER DITTEL" radio is all
respects, quality, design, function and format.......No question the Walter
Dittel radio's are among the very best ever produced for glider use....and a
Walter Dittel (current models) radio draws and operates on lower current
than nearly all the rest, operating 100% even well below 11 volts.
Voltage (level) isn't however the only criteria, you have to have Amps
(Capacity) also....
Always question your voltmeter as well.......if you are relying on the
voltmeter in an L/Nav or for that matter, in any flight computer or even a
separate voltmeters you are reading what that voltmeter (was) calibrated
to....and often they are misleading, you can also have volts and not
capacity...so though the voltmeter may show a higher value at idle, when
loaded, transmitting for instance, with a low capacity battery source you
will lose voltage quickly. Also, voltage at the meter (Voltmeter in computer
or otherwise) may not be the same voltage at the transmitter......cable
size, cable length, fuses, circuit breakers, all have a diminishing effect
on available current and voltage at the final source (Radio). And without
enough amperage capacity the voltage at the radio may be too low to Tx even
though at lower voltage the Rx will be OK.
As to others receiving your transmissions, it will make no difference if
they are using a cheaper handheld radio or the best panle mounted receiver
.....radio transmissions are either good or bad....and battery voltage will
have very little to do with Tx range or the receivers ability on the other
end.....if you have a low voltage, too low for the transmitter it will
normally come off as a garbled to whatever receiver gets your signal.
Finally, some radios are more voltage sensitive than others, and won't
operate fully at too low a voltage, where others can, and of course some
draw more current on standby than others. Most people "assume" that because
a radio has a very low standby current requirement, that it will be much
easier on batteries, Standby currents are almost always very low on most
radios we would commonly use in gliders since few if any have bright LED
displays or need to run warm like older tube radios did, and "most" will
draw very similar currents on Tx, as long as their output power is
similar..so if you get High Tx power ratings, you will also get high current
requirements in your choice of radios....for our purposes, even 1 watt
(carrier) transmitters will be more than enough providing your antenna is
good and proper.
Finally..since most better radios will operate at reasonable low (and high)
voltages I suggest using 12V battery set-ups over 14 Volts.....providing you
are using the same physical size (lead and acid) since in the 12V set-up you
will be able to carry a larger capacity battery (Amp hours)..also if you
feed the radio and other equipment at higher voltage, the capacity
(use)(((amps))) will be drawn at a higher rate as well....meaning the
battery will be drained more quickly at higher voltage.and though it has
further to fall to get to the critical level than the lower voltage set, it
will fall quicker.and with any battery, once it gets used and the capacity
becomes lower, it will fall very, very fast to where it is unusable.
I hope my explanations are correct and not too rambling.....
Tim
Wings & Wheels
www.wingsandwheels.com

> I fly with a Dittle Radio.
> If the radio is on but I do not talk, my 7AH 12V battery lasts about 4.5
> hour with the usual LNav, logger and 1530 Ipaq. The battery will read
> about 11.8 volts after that time. At that point if I make a call on the
> radio the chances are I will not be heard unless I am close to the field.
> That is due in large part the hand held radios seem not to do very well
> when it comes to receiving a call from a radio with lower battery power. I
> have made it a habit of switching to the reserve battery for my final
> glide and use this battery again the next day while I charge up the other
> one over night. I had an experience recently whereby heaved in the
> cockpit. I tried to make a call, that I would land in about 1/2 hour. I
> needed a bucket of hot water and clean closing. I was not received as I
> forgot to switch the battery. Lucky for me my call was being relayed and
> my wife
> was ready with the goods.
> Regards Udo
>
>

Bill Daniels

September 30th 05, 04:39 PM

"Tim Mara" > wrote in message
...
> What "Dittel" Radio?
> I hear this very commonly that "I have a Dittel" radio.....and I'm sure
most
> people "assume" (and we all know what that means) that a "Dittel" radio is
a
> "Walter Dittel" radio .....If it's an ATR (Dittel) of any kind then it is
an
> "AVIONIC DITTEL" which is far from the "WALTER DITTEL" radio is all
> respects, quality, design, function and format.......No question the
Walter
> Dittel radio's are among the very best ever produced for glider use....and
a
> Walter Dittel (current models) radio draws and operates on lower current
> than nearly all the rest, operating 100% even well below 11 volts.
> Voltage (level) isn't however the only criteria, you have to have Amps
> (Capacity) also....
> Always question your voltmeter as well.......if you are relying on the
> voltmeter in an L/Nav or for that matter, in any flight computer or even a
> separate voltmeters you are reading what that voltmeter (was) calibrated
> to....and often they are misleading, you can also have volts and not
> capacity...so though the voltmeter may show a higher value at idle, when
> loaded, transmitting for instance, with a low capacity battery source you
> will lose voltage quickly. Also, voltage at the meter (Voltmeter in
computer
> or otherwise) may not be the same voltage at the transmitter......cable
> size, cable length, fuses, circuit breakers, all have a diminishing effect
> on available current and voltage at the final source (Radio). And without
> enough amperage capacity the voltage at the radio may be too low to Tx
even
> though at lower voltage the Rx will be OK.
> As to others receiving your transmissions, it will make no difference if
> they are using a cheaper handheld radio or the best panle mounted receiver
> ....radio transmissions are either good or bad....and battery voltage will
> have very little to do with Tx range or the receivers ability on the other
> end.....if you have a low voltage, too low for the transmitter it will
> normally come off as a garbled to whatever receiver gets your signal.
> Finally, some radios are more voltage sensitive than others, and won't
> operate fully at too low a voltage, where others can, and of course some
> draw more current on standby than others. Most people "assume" that
because
> a radio has a very low standby current requirement, that it will be much
> easier on batteries, Standby currents are almost always very low on most
> radios we would commonly use in gliders since few if any have bright LED
> displays or need to run warm like older tube radios did, and "most" will
> draw very similar currents on Tx, as long as their output power is
> similar..so if you get High Tx power ratings, you will also get high
current
> requirements in your choice of radios....for our purposes, even 1 watt
> (carrier) transmitters will be more than enough providing your antenna is
> good and proper.
> Finally..since most better radios will operate at reasonable low (and
high)
> voltages I suggest using 12V battery set-ups over 14 Volts.....providing
you
> are using the same physical size (lead and acid) since in the 12V set-up
you
> will be able to carry a larger capacity battery (Amp hours)..also if you
> feed the radio and other equipment at higher voltage, the capacity
> (use)(((amps))) will be drawn at a higher rate as well....meaning the
> battery will be drained more quickly at higher voltage.and though it has
> further to fall to get to the critical level than the lower voltage set,
it
> will fall quicker.and with any battery, once it gets used and the capacity
> becomes lower, it will fall very, very fast to where it is unusable.
> I hope my explanations are correct and not too rambling.....
> Tim
> Wings & Wheels
> www.wingsandwheels.com
>

Tim, your post is both enlightening and, as usual, very helpful.

It leads me to think that transceivers have different power demand
characteristics than varios and glide computers. Might not this lead to two
different battery packs, one optimized for the high current demand of
transceivers and one optimized for the low current demand of varios and
glide computers?

Bill Daniels

Tim Mara

September 30th 05, 05:17 PM

I don't think so......a "good" battery should easily meet the demands we as
glider owners and pilots might have....you'll find most variometers and
flight computers as well as radios have quite wide voltage ranges and as
radios typically are happy at about 11-15 volts and most variometers can
handle quite well even wider ranges, typically from 9-16 volts a single
"good" battery should work nicely....having a back-up for the minimum
essential like the 9v battery back-up offered on Borgelt B-40's is a nice
extra reserve to get you home......but aside from that, if you are having
more than the very occasional main battery failure you probably just need to
replace the old battery if it's getting weak, or up the AH capacity of the
battery to a larger size...I am a very firm believer of the KISS
principal...
good luck and best regards
Tim
Wings & Wheels
www.wingsandwheels.com

"Bill Daniels" > wrote in message
...
> Tim, your post is both enlightening and, as usual, very helpful.
>
> It leads me to think that transceivers have different power demand
> characteristics than varios and glide computers. Might not this lead to
> two
> different battery packs, one optimized for the high current demand of
> transceivers and one optimized for the low current demand of varios and
> glide computers?
>
> Bill Daniels
>
>

bumper

September 30th 05, 06:06 PM

By now, most will realize that electricity is pretty dangerous stuff and not
to be trifled with. Yeah, it's maybe okay in small doses, flashlight
batteries come to mind as being pretty safe if not swallowed.

Not a believer? If you want to see the incredible destructive power that
lurks in seemingly innocent, but higher voltage batteries, try touching the
terminals on a cute little 9 volt battery to a scrap of fine steel wool!!
(use caution and make sure the steel wool in on a surface that won't burn)

Yup, 12 volts DC is right at the maximum sane voltage. Any more is downright
foolish. In fact, the force fields that result from adding just 2 additional
volts (14 volts DC) will cause the hapless pilot to undergo some sort of
cultish brain damage. In some cases these poor deranged pilots will then
start preaching on street corners, warning those who use lesser voltages
that the end is near and they will be discharged.

Curiously, by abandoning the idea of using DC (direct current), and
switching all systems over to AC, alternating current, one can safely
increase voltage doses up to about 120 VAC or so, with little attendent risk
of dain bramage. Beyond that, there is the ever present risk of
vaporization. Which is, of course, why pilots should do their best to avoid
high voltage transmission lines.

all the best,

bumper (12 volts DC and proud of it)

Paul Remde

September 30th 05, 07:09 PM

OK. I'm laughing out loud at that one. Well done.

Paul Remde

"bumper" > wrote in message ...
> By now, most will realize that electricity is pretty dangerous stuff and
> not to be trifled with. Yeah, it's maybe okay in small doses, flashlight
> batteries come to mind as being pretty safe if not swallowed.
>
> Not a believer? If you want to see the incredible destructive power that
> lurks in seemingly innocent, but higher voltage batteries, try touching
> the terminals on a cute little 9 volt battery to a scrap of fine steel
> wool!! (use caution and make sure the steel wool in on a surface that
> won't burn)
>
> Yup, 12 volts DC is right at the maximum sane voltage. Any more is
> downright foolish. In fact, the force fields that result from adding just
> 2 additional volts (14 volts DC) will cause the hapless pilot to undergo
> some sort of cultish brain damage. In some cases these poor deranged
> pilots will then start preaching on street corners, warning those who use
> lesser voltages that the end is near and they will be discharged.
>
> Curiously, by abandoning the idea of using DC (direct current), and
> switching all systems over to AC, alternating current, one can safely
> increase voltage doses up to about 120 VAC or so, with little attendent
> risk of dain bramage. Beyond that, there is the ever present risk of
> vaporization. Which is, of course, why pilots should do their best to
> avoid high voltage transmission lines.
>
> all the best,
>
> bumper (12 volts DC and proud of it)
>

Mike the Strike

September 30th 05, 08:18 PM

When I started this thread, all I was looking for was a source for a
battery for my Discus fin box. My backup battery under my panel is
about to be switched to a dedicated source to my new transponder and I
like the idea of having a separate source for my main panel instruments
and radio just in case. I lost my main battery in a glider some years
ago when a wire joint failed at the faston tab at the battery, so I
believe that a backup source is common sense.

I was considering using a 14 V seven-stack of D+ del cells for my tail
fin to take account of the extra voltage drop in the longer wiring to
the fin but decided it wasn't worth the hassle when I calculated 12 V
would work fine for the hour or two I might need it.

In any case, I hadn't intended starting rival polemics about 12 V
versus 14 V systems!

Having said that, some of the arguments for 14 V sources don't seem to
make much sense. One main argument seems to be that the higher voltage
removes the need for a second backup. Presumably using this thinking
the authors have installed heavy-duty tires on their cars and removed
their spares.

The extra 20% to 30% power from a radio transmitter also makes very
little difference. If the radio quits because of low voltage, that's a
different matter, but the extra power from a working radio is
inconsequential. Most communication problems arise from either bad
antennas or defective ones. The rubber duckies on handhelds are a
particular example of this and are horribly inefficient. Some years
ago, I did tests on the 144 MHz FM amateur frequencies from a glider
and using standard commercial equipment with good antennas was able to
maintain perfect communications with 1 watt at up to a hundred miles
with line-of-sight conditions. The 120 MHz AM aircraft radios might
not be quite so good, but a couple of watts should be good enough for
50 miles or more.

Eric Greenwell

October 1st 05, 04:26 AM

Udo Rumpf wrote:

>> It's possible you have a problem not related to the voltage; e.g.,
>> maybe the voltage is dropping well below the 11.8 volts when the
>> transmitter is keyed, or the radio is not functioning within
>> specifications.
>>
>> Eric Greenwell
>
>
> I have a 720A Dittle radio
> Power requirements;
> Receive .1 - .4 amps
> Transmit (tone) 1.4 amps (.8 amps unmodulated)
> The 11.8 volts I was referring to is before transmit.
> If I remember correctly when the battery is fully charged
> and I hit the transmit button the voltage drops from 12.7 to 12.2.
> Udo

With the battery run down to 11.8 volts, measure the voltage right at
the radio connector while keying the transmitter for 5-10 seconds. If it
drops more than it does when the battery is fully (or nearly so)
charged, the problem might be the battery.

However....
I found a German manual for the ATR720A (and ATR70C in English) on the
Filser site (I think they took over the radios from Avionic Dittel).
The specifications don't make any mention of what voltage range the
radio will function over, so I suspect 12 volt battery operation wasn't
on their minds when it was designed. This appears to be an older design
radio, and likely is one that would benefit from 14 volt operation.

So, if it's not the battery, your choices seem to be a modern radio
(like the Walter Dittel FSG 2T I mentioned) or going to a 14 volt
battery pack. Or waiting till you get closer to the airfield to make
your call :^)

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Udo Rumpf

October 1st 05, 01:35 PM

>> I have a 720A Dittle radio
>> Power requirements;
>> Receive .1 - .4 amps
>> Transmit (tone) 1.4 amps (.8 amps unmodulated)
>> The 11.8 volts I was referring to is before transmit.
>> If I remember correctly when the battery is fully charged
>> and I hit the transmit button the voltage drops from 12.7 to 12.2.
>> Udo
>
> With the battery run down to 11.8 volts, measure the voltage right at
> the radio connector while keying the transmitter for 5-10 seconds. If it
> drops more than it does when the battery is fully (or nearly so)
> charged, the problem might be the battery.
>
> However....
> I found a German manual for the ATR720A (and ATR70C in English) on the
> Filser site (I think they took over the radios from Avionic Dittel).
> The specifications don't make any mention of what voltage range the
> radio will function over, so I suspect 12 volt battery operation wasn't
> on their minds when it was designed. This appears to be an older design
> radio, and likely is one that would benefit from 14 volt operation.
>
> So, if it's not the battery, your choices seem to be a modern radio
> (like the Walter Dittel FSG 2T I mentioned) or going to a 14 volt
> battery pack. Or waiting till you get closer to the airfield to make
> your call :^)
>
> Eric Greenwell

I have this Radio now for many years.
Based on what you and Tim are saying, I concluded that
this radio does not perform very well at lower voltage.
Only in the past couple of years while flying a glider with restrictive
space for a batteries (the standard 12v 7amp) have I noticed any
deficiency at low voltage even with fresh sets of batteries.
also this radio seem to eat more on stand by.
Prior to this I had no restriction in capacity and the problem never
came up. Other then that the radio works fine and has good range
when the voltage is up.
Thanks
Udo

bumper

October 1st 05, 03:20 PM

Paul Remde mentioned that he replaces his batteries after two years of use.

The sealed lead acid batteries we use, start life with a given capacity,
rated in amp hours. After manufacture, and during the first several
charge/discharge cycles, these batteries will actually gain a small amount
of capacity. After that, it's all downhill, with the battery losing capacity
over time and discharge cycles.

In the alarm industry, we replace the batteries at 5 year intervals. At this
point, most of the batteries will be down to about 70% of capacity. However,
these batteries have a pretty easy life, rarely being called upon to provide
power and generally not bieng discharged deeply.

In a glider, life for a battery is tough. Deep discharge cycles and wild
temperature swings being the norm. Generally, discharging a lead acid below
80% charge will have an impact on its remaining life, below 50% is not
recommended. So life will be short, so to speak.

I agree with Paul, replacing batteries often is cheap insurance. I change
mine at 3 years and always store them fully charged.

all the best,

bumper (12 volts and proud of it!)

Eric Greenwell

October 1st 05, 04:10 PM

Udo Rumpf wrote:

>> So, if it's not the battery, your choices seem to be a modern radio
>> (like the Walter Dittel FSG 2T I mentioned) or going to a 14 volt
>> battery pack. Or waiting till you get closer to the airfield to make
>> your call :^)
>>
>> Eric Greenwell
>
>
> I have this Radio now for many years.
> Based on what you and Tim are saying, I concluded that
> this radio does not perform very well at lower voltage.
> Only in the past couple of years while flying a glider with restrictive
> space for a batteries (the standard 12v 7amp) have I noticed any
> deficiency at low voltage even with fresh sets of batteries.
> also this radio seem to eat more on stand by.
> Prior to this I had no restriction in capacity and the problem never
> came up. Other then that the radio works fine and has good range when
> the voltage is up.

It's possible the radio is not performing as well at low voltages as it
did when new. Electronic parts do age, particularly capacitors. If this
is the problem, a clever and determined technician might be able to
discover the correct parts to replace. A couple calls to people that
repair these would be worth the effort - perhaps there are common
problems that are cheaply fixed.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Graeme Cant

October 3rd 05, 02:26 PM

T o d d P a t t i s t wrote:

> I've run 12 volts and I've run 14 volts. The charger
> comment above is the main disadvantage of 14 volts. The
> secondary disadvantage is the "non-standard battery stack"
> may not want to fit into your standard-sized battery
> location.
>
> An advantage to 14 volt is more radio power/longer range on
> transmit. Modern radios don't cut out at lower voltage, like
> older radios that assumed 13.8 volts, but they all drive the
> output stages off the full voltage - the more voltage, the
> more output power.
>
> Other advantages are that you can run the battery longer
> before it gets too low, and for any switchmode DC-DC
> downconverters, such as I use for my IPAQ's 5 volt...

What about getting the best of both worlds? It seems agreed that only
the radio's performance improves with higher voltage. Why not keep a
12V system with its easy charging and standard sizes but add a DC-DC UP
converter into the radio circuit so that a constant 13-14V is supplied
to the radio even though the battery supply voltage drops?

I have no technical skill in electronics - meaning my ego isn't involved
if I'm told it's a stupid idea. Would it just be a further drain on the
battery or would it usefully improve the radio's range? Does such a
converter exist?

More specifically on batteries, my glider has 4 x 6V 12ah cells arranged
in two series pairs connected in parallel (no, not my idea, the
manufacturer did it) which have reached the end of their life. The
original cells are clearly a carefully matched set (marked 6.47, 6.47,
6.45, 6.46).

How important is it that I match the replacements - and on which
characteristics? The Yuasa website seems to imply that the only
important things are that the cells be the same and the same age.

Oh ...and the cells are almost impossible to remove from the glider so
they have to be charged in place in the series/parallel configuration.

Any advice welcomed.

Graeme Cant

bumper

October 3rd 05, 04:25 PM

"Graeme Cant" > wrote in message
...
>T o d d P a t t i s t wrote:
> What about getting the best of both worlds? It seems agreed that only the
> radio's performance improves with higher voltage. Why not keep a 12V
> system with its easy charging and standard sizes but add a DC-DC UP
> converter into the radio circuit so that a constant 13-14V is supplied to
> the radio even though the battery supply voltage drops?

By the time most modern radios would start to falter, the battery is already
pretty much discharged. Using an up-converter is this circumstance would
only result in a very limited amount of additional radio use - - along with
a very discharged battery!

Better and cheaper to insure you have adequate battery capacity by replacing
batteries on a regular basis, as these batteries lose capacity with time (I
replace mine at 3 year intervals - - 2 years is probably better). If room
allows, consider adding an additional battery pack.

Fortunately, Schleicher was kind enough to install two 12 volt 18 amp hour
batteries in my ASH26E (bless their little hearts!).

bumper

Eric Greenwell

October 3rd 05, 05:04 PM

Graeme Cant wrote:

> What about getting the best of both worlds? It seems agreed that only
> the radio's performance improves with higher voltage. Why not keep a
> 12V system with its easy charging and standard sizes but add a DC-DC UP
> converter into the radio circuit so that a constant 13-14V is supplied
> to the radio even though the battery supply voltage drops?
>
> I have no technical skill in electronics - meaning my ego isn't involved
> if I'm told it's a stupid idea. Would it just be a further drain on the
> battery or would it usefully improve the radio's range?

Older radios would generally benefit, but modern radios would see less
improvement.

> Does such a
> converter exist?

Yes; in fact, modern radios often have exactly this kind of power supply
built into them (my Becker transponder is an example of this). A
potential problem with an "add-on" external unit is the losses of the
conversion might overcome the value of the improved operation. I hope
someone will determine what's available out there and let's us know how
good they are.

>
> More specifically on batteries, my glider has 4 x 6V 12ah cells arranged
> in two series pairs connected in parallel (no, not my idea, the
> manufacturer did it) which have reached the end of their life.

I've always wondered why DG thought that was a good idea.

> The
> original cells are clearly a carefully matched set (marked 6.47, 6.47,
> 6.45, 6.46).
>
> How important is it that I match the replacements - and on which
> characteristics? The Yuasa website seems to imply that the only
> important things are that the cells be the same and the same age.

The DG owners here seem to just buy 4 batteries at the same time from
the same place and not worry about matching them. If you don't get a
good answer here, try the DG owners group listed on the
www.motorglider.org site.

>
> Oh ...and the cells are almost impossible to remove from the glider so
> they have to be charged in place in the series/parallel configuration.

Again, the DG owners group will offer a plethora of ideas, but this is
common for motorgliders anyway. The batteries are usually large enough
that they have to be mounted more firmly than the usual 7 AH unit,
making it hard to remove them. A solar panel on the trailer is a
favorite (or one placed next to the glider if it's tied down). I just
put charger on mine while it's at home in the trailer, then remove it
after it's charged. There's no need to keep it "topped up" if you are
flying at least once every month or so.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Malcolm Austin

October 4th 05, 08:51 AM

Hi,
Just to dive in here, with a slightly off track comment. The
benefits of extra
voltage on the radio transmit are not worth the effort. A quick trawl
through
the figures shows that you need to make an x10 output improvement in output
to
hear/notice it at the other end.

Changing the coax feeding the antenna to a good quality low loss grade,
followed
by tuning the antenna for the frequency range your using, would give more
useful benefits. The receive improvement gained here, is also not to be
sniffed at.

I wonder how many have put a VSWR meter on their setup? Any SWR above 1.5
is going to be a detrimental. On most gliders I would estimate that the
power reaching
the antenna is only 50% of that, that left the radio!!

Malcolm - G3REM (but only a poor, K6 pilot)

"T o d d P a t t i s t" > wrote in message
...
> "bumper" > wrote:
>
>>By the time most modern radios would start to falter, the battery is
>>already
>>pretty much discharged. Using an up-converter is this circumstance would
>>only result in a very limited amount of additional radio use - - along
>>with
>>a very discharged battery!
>
> I don't think he was advocating an up-converter to increase
> voltage when the battery was dying. I think he was
> suggesting it for the additional transmitted power you would
> get from 14 volts even when the 12V battery is fresh. Even
> if it was practical (which I doubt) you'd be losing battery
> capacity to gain the higher voltage - that's probably not a
> good trade-off for reasons discussed in Tim Mara's post.
>
>
> T o d d P a t t i s t - "WH" Ventus C
> (Remove DONTSPAMME from address to email reply.)

Tony Verhulst

October 4th 05, 02:12 PM

> Changing the coax feeding the antenna to a good quality low loss grade,
> followed
> by tuning the antenna for the frequency range your using, would give more
> useful benefits. The receive improvement gained here, is also not to be
> sniffed at.

Just how do you tune an antenna? In the old CB days we would ajdust the
lenght of the antenna until we got a good SWR. I can't see cutting into
the tail of my LS6 to do that.

Tony V.

David Kinsell

October 4th 05, 02:31 PM

Tony Verhulst wrote:
>
>> Changing the coax feeding the antenna to a good quality low loss
>> grade, followed
>> by tuning the antenna for the frequency range your using, would give more
>> useful benefits. The receive improvement gained here, is also not to
>> be sniffed at.
>
> Just how do you tune an antenna? In the old CB days we would ajdust the
> lenght of the antenna until we got a good SWR. I can't see cutting into
> the tail of my LS6 to do that.
>
> Tony V.

I measured it in my LS4 once, and saw something really good, about 1.1:1.

If Malcolm believes you need a 10X factor in transmitter power to make
a noticeable improvement, then I suppose he'd also believe you need to
increase the radiated power 10X by tuning in order to make a difference.
No factory installation is going to be subject to that kind of
improvement, unless you have an open or short somewhere in the system.

-Dave

Eric Greenwell

October 4th 05, 07:17 PM

T o d d P a t t i s t wrote:
> Eric Greenwell > wrote:
>
>
>>> Does such a converter exist?
>>
>>Yes; in fact, modern radios often have exactly this kind of power supply
>>built into them (my Becker transponder is an example of this).
>
> Does your Becker upconvert the voltage to the power output
> transistors, or just the control electronics?

I'm sure it controls the voltage to the output stage. Whether it's
upping or downing it probably depends on the input voltage (supply
voltage is given at 9.5-32.2 volts), but I don't know what voltage the
output stage operates at. The rest of the radio might could just use a
voltage regulator off the incoming voltage, but again, just a guess.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

[email protected]

October 4th 05, 10:42 PM

That is just pure nonsense (the up vs down part). You can buy a 30W
(15V @ 2A) dc-dc converter for $62 from Mouser (search for
UHE-15/2000-Q12). The description says the input is 24V, but it really
is 9-36V, which should cover just about any battery you want to come up
with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
lower power ones even cheaper. If that makes your 14V heart feel
better, go for it (it won't damage your radio).

Tom Seim
2G DG-400

David Kinsell

October 5th 05, 02:21 AM

Eric Greenwell wrote:
> Graeme Cant wrote:
>
>> What about getting the best of both worlds? It seems agreed that only
>> the radio's performance improves with higher voltage. Why not keep a
>> 12V system with its easy charging and standard sizes but add a DC-DC
>> UP converter into the radio circuit so that a constant 13-14V is
>> supplied to the radio even though the battery supply voltage drops?
>>

>> Does such a converter exist?
>
> Yes; in fact, modern radios often have exactly this kind of power supply
> built into them (my Becker transponder is an example of this).

The truth is virtually no aircraft radios have upconverters built into them.
They switch high currents at high voltage at low RF frequencies. A nasty
thing to be building into a radio with a sensitive receiver. The converters
put out harmonics from their high-power square waves going well into the
aircraft band.

The only reason transponders have them built in is they have to generate
high voltage internally to create the multi-hundred watt pulses they put out.
Certainly not to humor a bunch of glider pilots too cheap to put together
a decent battery.

-Dave

Jim Kelly

October 5th 05, 07:18 AM

Another interesting observation:

In a recent evaluation of our club's glider batteries (all 7AH
12v), we observed a very significant variation in weight. Is it
reasonable to deduce that a light battery cannot provide the same
hours of operation as a well designed heavier battery of the same
physical size? If so then we should also be watching out for
cheap-and-nasty batteries, where the manufacturer is skimping on
the lead content!

Cheers,

Jim Kelly.

"Malcolm Austin" > wrote in message
...
Hi,
Just to dive in here, with a slightly off track comment.
The
benefits of extra
voltage on the radio transmit are not worth the effort. A quick
trawl
through
the figures shows that you need to make an x10 output improvement
in output
to
hear/notice it at the other end.

Changing the coax feeding the antenna to a good quality low loss
grade,
followed
by tuning the antenna for the frequency range your using, would
give more
useful benefits. The receive improvement gained here, is also
not to be
sniffed at.

I wonder how many have put a VSWR meter on their setup? Any SWR
above 1.5
is going to be a detrimental. On most gliders I would estimate
that the
power reaching
the antenna is only 50% of that, that left the radio!!

Malcolm - G3REM (but only a poor, K6 pilot)

"T o d d P a t t i s t" > wrote in
message
...
> "bumper" > wrote:
>
>>By the time most modern radios would start to falter, the
>>battery is
>>already
>>pretty much discharged. Using an up-converter is this
>>circumstance would
>>only result in a very limited amount of additional radio
>>use - - along
>>with
>>a very discharged battery!
>
> I don't think he was advocating an up-converter to increase
> voltage when the battery was dying. I think he was
> suggesting it for the additional transmitted power you would
> get from 14 volts even when the 12V battery is fresh. Even
> if it was practical (which I doubt) you'd be losing battery
> capacity to gain the higher voltage - that's probably not a
> good trade-off for reasons discussed in Tim Mara's post.
>
>
> T o d d P a t t i s t - "WH" Ventus C
> (Remove DONTSPAMME from address to email reply.)

Jim Vincent

October 5th 05, 03:36 PM

> wrote in message
oups.com...
> That is just pure nonsense (the up vs down part). You can buy a 30W
> (15V @ 2A) dc-dc converter for $62 from Mouser (search for
> UHE-15/2000-Q12). The description says the input is 24V, but it really
> is 9-36V, which should cover just about any battery you want to come up
> with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
> lower power ones even cheaper. If that makes your 14V heart feel
> better, go for it (it won't damage your radio).
>
> Tom Seim
> 2G DG-400
>

Get one of these for $45 and it will take your 12 V input and upconvert it
to 14V, handle 2A and be about 83% efficient.

http://www.dimensionengineering.com/AnyVolt.htm

I wish I had been available two years ago when I built my own 13.9V
upconverter.

Eric Greenwell

October 5th 05, 05:00 PM

Jim Vincent wrote:
> > wrote in message
> oups.com...
>
>>That is just pure nonsense (the up vs down part). You can buy a 30W
>>(15V @ 2A) dc-dc converter for $62 from Mouser (search for
>>UHE-15/2000-Q12). The description says the input is 24V, but it really
>>is 9-36V, which should cover just about any battery you want to come up
>>with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
>>lower power ones even cheaper. If that makes your 14V heart feel
>>better, go for it (it won't damage your radio).
>>
>>Tom Seim
>>2G DG-400
>>
>
>
> Get one of these for $45 and it will take your 12 V input and upconvert it
> to 14V, handle 2A and be about 83% efficient.
>
> http://www.dimensionengineering.com/AnyVolt.htm
>
> I wish I had been available two years ago when I built my own 13.9V
> upconverter.

Did you use it with your glider transceiver? How has it worked out, and
do you have any problems with noise in the receiver from the converter?

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Paul Remde

October 5th 05, 05:04 PM

Hi,

It is my belief that all the work required to make an "upconverter" will
lead to only minimal increases in your radios transmit power (10 to 20%?).
It doesn't seem worth it to me. I vote 12V.

Paul Remde

"Jim Vincent" > wrote in message
. ..
>
> > wrote in message
> oups.com...
>> That is just pure nonsense (the up vs down part). You can buy a 30W
>> (15V @ 2A) dc-dc converter for $62 from Mouser (search for
>> UHE-15/2000-Q12). The description says the input is 24V, but it really
>> is 9-36V, which should cover just about any battery you want to come up
>> with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
>> lower power ones even cheaper. If that makes your 14V heart feel
>> better, go for it (it won't damage your radio).
>>
>> Tom Seim
>> 2G DG-400
>>
>
> Get one of these for $45 and it will take your 12 V input and upconvert it
> to 14V, handle 2A and be about 83% efficient.
>
> http://www.dimensionengineering.com/AnyVolt.htm
>
> I wish I had been available two years ago when I built my own 13.9V
> upconverter.
>
>
>

[email protected]

October 5th 05, 05:36 PM

Jim Vincent wrote:
> > wrote in message
> oups.com...
> > That is just pure nonsense (the up vs down part). You can buy a 30W
> > (15V @ 2A) dc-dc converter for $62 from Mouser (search for
> > UHE-15/2000-Q12). The description says the input is 24V, but it really
> > is 9-36V, which should cover just about any battery you want to come up
> > with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
> > lower power ones even cheaper. If that makes your 14V heart feel
> > better, go for it (it won't damage your radio).
> >
> > Tom Seim
> > 2G DG-400
> >
>
> Get one of these for $45 and it will take your 12 V input and upconvert it
> to 14V, handle 2A and be about 83% efficient.
>
> http://www.dimensionengineering.com/AnyVolt.htm
>
> I wish I had been available two years ago when I built my own 13.9V
> upconverter.

This looks like a hobbyist product that would have to put into an
enclosure before using in a glider. What I found is a commercial dc-dc
converter that is in volume production from a company that has an
established reputation. It is also a much smaller package, has
over-voltage protection & short circuit protection, and meets all
specifications at -40 C. I doubt that the other unit has even been
tested at anything but room temperature. The level of testing and
quality assurance that a company like Datel has to offer should not be
underestimated.

Tom Seim
2G DG-400

Eric Greenwell

October 5th 05, 05:41 PM

Paul Remde wrote:

> Hi,
>
> It is my belief that all the work required to make an "upconverter" will
> lead to only minimal increases in your radios transmit power (10 to 20%?).
> It doesn't seem worth it to me. I vote 12V.

Even a 30% power output increase would yield only about 15% range
increase, so if one is otherwise happy with the radio's performance, I
agree. It might let you operate the radio for a longer time off the same
12 volt battery, if the radio isn't working satisfactorily below, say,
11.8 volts or so. If so, a $45-$60 converter would be a lot cheaper than
a new radio, easier and cheaper than trying to squeeze in a 2 volt cell
and buying a 14 volt charger to go with it, or fumbling with a handheld
when the panel radio quits.

As Dave K. suggests, noise from the switcher is a potential concern, but
I believe an external unit like the ones mentioned shouldn't be a
problem. We already have one or more switchers without problems in our
gliders to run the Ipaqs and transponders, and transceivers are well
shielded.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Jim Vincent

October 5th 05, 05:47 PM

"Eric Greenwell" > wrote in message
...
> Jim Vincent wrote:
>> > wrote in message
>> oups.com...
>>
>>>That is just pure nonsense (the up vs down part). You can buy a 30W
>>>(15V @ 2A) dc-dc converter for $62 from Mouser (search for
>>>UHE-15/2000-Q12). The description says the input is 24V, but it really
>>>is 9-36V, which should cover just about any battery you want to come up
>>>with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
>>>lower power ones even cheaper. If that makes your 14V heart feel
>>>better, go for it (it won't damage your radio).
>>>
>>>Tom Seim
>>>2G DG-400
>>>
>>
>>
>> Get one of these for $45 and it will take your 12 V input and upconvert
>> it to 14V, handle 2A and be about 83% efficient.
>>
>> http://www.dimensionengineering.com/AnyVolt.htm
>>
>> I wish I had been available two years ago when I built my own 13.9V
>> upconverter.
>
> Did you use it with your glider transceiver? How has it worked out, and do
> you have any problems with noise in the receiver from the converter?
>
>
> --
> Change "netto" to "net" to email me directly
>
> Eric Greenwell
> Washington State
> USA

Eric, I have not used the one I reference here. I have only used the one I
built. It has worked fine.I have not experienced any noise issues.

My premise for adding this to my ship is for the rare situation when the
battery is near death and I need to make an emergency transmission. I flip
one switch to make the GPS and Palm Pilot run off their own internal
batteries and flip another to activate the upconverter. BTW, I have a third
switch that selects either the main battery or a small backup battery
dedicated to the GPS secure data logger for badge purposes.

Jim Vincent

October 5th 05, 05:55 PM

> wrote in message
oups.com...
>
> Jim Vincent wrote:
>> > wrote in message
>> oups.com...
>> > That is just pure nonsense (the up vs down part). You can buy a 30W
>> > (15V @ 2A) dc-dc converter for $62 from Mouser (search for
>> > UHE-15/2000-Q12). The description says the input is 24V, but it really
>> > is 9-36V, which should cover just about any battery you want to come up
>> > with. The thing is 88% efficient and occupies 1.5 in^3. You can buy
>> > lower power ones even cheaper. If that makes your 14V heart feel
>> > better, go for it (it won't damage your radio).
>> >
>> > Tom Seim
>> > 2G DG-400
>> >
>>
>> Get one of these for $45 and it will take your 12 V input and upconvert
>> it
>> to 14V, handle 2A and be about 83% efficient.
>>
>> http://www.dimensionengineering.com/AnyVolt.htm
>>
>> I wish I had been available two years ago when I built my own 13.9V
>> upconverter.
>
> This looks like a hobbyist product that would have to put into an
> enclosure before using in a glider. What I found is a commercial dc-dc
> converter that is in volume production from a company that has an
> established reputation. It is also a much smaller package, has
> over-voltage protection & short circuit protection, and meets all
> specifications at -40 C. I doubt that the other unit has even been
> tested at anything but room temperature. The level of testing and
> quality assurance that a company like Datel has to offer should not be
> underestimated.
>
> Tom Seim
> 2G DG-400
>
Tom, my guess is the product is built with off the shelf components that are
more than adequate for our purposes. If I was to get one, I would pull the
display and Amp/Volt switch and mount them on my panel. The rest I would
put in a standard Radio Shack enclosure, drilled out for cooling/venting
purposes.

Regarding Datel, do you think they're in compliance with MILSPEC-1540B and
have been fully vibe/shock/thermal tested....I doubt it. Great that you
found another vendor, but please don't dis a vendor because they cater to
hobbyists. Dimension Engineering caters to radio control aircraft, which as
you surely know experience diverse environments. If their reliability was
bad, they'd be out of business in no time...s**t listed too on every
newsgroup. I'm sure either vendor would work just fine.

Bill Daniels

October 5th 05, 06:22 PM

> Paul Remde wrote:
>
> > Hi,
> >
> > It is my belief that all the work required to make an "upconverter" will
> > lead to only minimal increases in your radios transmit power (10 to
20%?).
> > It doesn't seem worth it to me. I vote 12V.
>

I agree. 14V seems to be a magnificent solution to a non-existent
problem.;)

This summer I was sitting on an airport ramp after 8 hours in the air and
talking to glider pilots 200 miles away - on a single '12V' - 7.5 AH SLA
battery that was 2 years old. The battery still showed 12.5 V while
transmitting.

I do get the impression that newer SLA's perform better than those sold a
few years ago. It's pretty clear that newer radios work much better on
lower voltages. Taken together, it's hard to see what improvements are
needed.

If I ever see the need for more power, I'll replace it with a 12 AH version
and not fool with two batteries and an 'A-B" switch. I'll replace the 7.5AH
before next season even if it seems to be working fine.

My regimen is to make sure the battery goes on a very good charger right
after each use where it remains under trickle charge until I need it again.
I never leave a battery partially charged.

Bill Daniels

Andy

October 5th 05, 07:15 PM

If the battery is near death will it provide the current required by
the upconverter? It's not magic and you can't get more power out of
the upconverter than you put in. I'm curious to know if you have
measured the performance with a "battery near death"?

An upconverter can't solve the available capacity problem. It can only
make it worse. (About 15 percent worse for the referenced converters).
They seem to be of no value except for powering equipment that will not
operate properly unless the available voltage is increased.

My prefered solution for emergencies is to have a handheld tranceiver
with an alkaline battery pack.

Jim Vincent

October 5th 05, 07:43 PM

"Andy" > wrote in message
oups.com...
> If the battery is near death will it provide the current required by
> the upconverter? It's not magic and you can't get more power out of
> the upconverter than you put in. I'm curious to know if you have
> measured the performance with a "battery near death"?
>
> An upconverter can't solve the available capacity problem. It can only
> make it worse. (About 15 percent worse for the referenced converters).
> They seem to be of no value except for powering equipment that will not
> operate properly unless the available voltage is increased.
>
> My prefered solution for emergencies is to have a handheld tranceiver
> with an alkaline battery pack.
>
Haven't tested near death, but actually was part of the thinking. If the
battery is near death, it has a little juice left. If the radio would not
tolerate a low voltage, then I could upconvert. Other part was optimizing
the power demands of the Dittle FSG-50 radio and Cambridge vario. Found no
real difference in performance between 12V and 13.9.
And yes, I do recognize the power losses.

[email protected]

October 6th 05, 09:38 PM

I do this stuff for a living, and have over 30 years experience. In
that time I have developed methods and instincts for evaluating vendors
(after you are burned a few times you get to be really careful). First,
I have been using Datel products for 30+ years and have a real comfort
zone with them. Second, I read the data sheet (which you can also do).
Except that you can't do that with Dimension Engineering because there
isn't one! Now, that is a major red flag in my book (maybe not yours).
And don't assume that just because somebody is selling something that
it works as advertised. That is, perhaps, the silliest thing you said.

If you want a MIL SPEC qualified dc-dc, they are available too. Try
Vicor. You'll just pay A LOT more. The Datel unit is known as COTS (for
commercial off the shelf).

I said that it looks like a hobbyist product, and it does. Since when
is that *DISSING* anybody? Furthermore, what I was saying was that it
was MADE by hobbyists. That are lots of well designed commercial
products FOR hobbyists, but that is not the situation here.

I stand by my original comments and would recommend for the Datel unit
and strongly against the Dimension Engineering. You, of course, are
entitled to your own opinion.

Tom Seim
2G DG-400

Jim Vincent

October 6th 05, 10:05 PM

> wrote in message
ups.com...
>I do this stuff for a living, and have over 30 years experience. In
> that time I have developed methods and instincts for evaluating vendors
> (after you are burned a few times you get to be really careful). First,
> I have been using Datel products for 30+ years and have a real comfort
> zone with them. Second, I read the data sheet (which you can also do).
> Except that you can't do that with Dimension Engineering because there
> isn't one! Now, that is a major red flag in my book (maybe not yours).
> And don't assume that just because somebody is selling something that
> it works as advertised. That is, perhaps, the silliest thing you said.
>
> If you want a MIL SPEC qualified dc-dc, they are available too. Try
> Vicor. You'll just pay A LOT more. The Datel unit is known as COTS (for
> commercial off the shelf).
>
> I said that it looks like a hobbyist product, and it does. Since when
> is that *DISSING* anybody? Furthermore, what I was saying was that it
> was MADE by hobbyists. That are lots of well designed commercial
> products FOR hobbyists, but that is not the situation here.
>
> I stand by my original comments and would recommend for the Datel unit
> and strongly against the Dimension Engineering. You, of course, are
> entitled to your own opinion.
>
> Tom Seim
> 2G DG-400
>

I'll be sure to keep this in mind the next time I buy a radio control system
from Futaba or JR or any of the other well known vendors in radio control
space that provide receivers, motors, batteries and other flight critical
devices used in radio control aircraft. In my thirty years of radio control
aircraft, I can think of very few, if any, devices that have not worked as
promised. Oh yeah, very few of them have data sheets.

At what point does a company mature from a start up to what you consider a
bonafide COTS? Oh, just because a product was made by hobbyists, it is not
as legit as one made for hobbyists? Your critical thinking skills sure are
sharp...note the sarcasm here, Tom.

I am glad your instincts and methods were so correct in determining DE's
reliability and suitability. I guess I just have to rely on my ten silly
years of testing, system engineering and integrating aerospace critical
rocket gear and thirty years of fooling around with silly radio control toys
as my baseline in evaluation skills. I also rely on the Internet community
as an excellent near realtime feedback mechanism on radio control products;
if a product does not work as promised, the company gets slammed.

In the context of how you used the tem "hobbyist," I am very comfortable
saying you were dising it. Taking your comment that this is the "silliest
thing" I've said, you're implying that the other things I've said were silly
as well, just not as silly. Well, thanks for your succinct evaluation and
critique. I now know that if I need the final authority on what is valid
and what is not, I'll just go to you.

[email protected]

October 6th 05, 10:47 PM

My, my. Are we getting a little testy here?

Actually, if you to Futaba's website you will find extensive data
sheets on their products. Futaba is, clearly, not garage shop opertion.

If you want to put something in your glider built by a garage shop
hobbyist, go right ahead. I will continue to be critical and not
recommend that course of action. I, too, am entitled to MY opinion.

Tom

Eric Greenwell

October 7th 05, 02:15 AM

Jim Vincent wrote:
> "Andy" > wrote in message
> oups.com...
>
>>If the battery is near death will it provide the current required by
>>the upconverter? It's not magic and you can't get more power out of
>>the upconverter than you put in. I'm curious to know if you have
>>measured the performance with a "battery near death"?

snip

>
> Haven't tested near death, but actually was part of the thinking. If the
> battery is near death, it has a little juice left. If the radio would not
> tolerate a low voltage, then I could upconvert.

This is an interesting idea. By using 12 volts until the radio is close
to unsatisfactory operation, you avoid the efficiency losses in the
converter. At that voltage, you switch on the converter and make
available the rest of the battery's capacity, though with a 10%-15%
capacity loss in the converter. Still, you'd get 90+% of the battery's
capacity, instead of 50% (or wherever your radio becomes unsatisfactory).

This might be a solution for Udo, the original poster. I suggest he try
the Datel converter (UHE-15/2000-Q12) mentioned by Tom Seim, as it is
cheap, very small, totally enclosed, wide temperature range, and with
excellent specifications for regulation, ripple, and
overload/overvoltage protection. I can't guarantee it will work since I
don't know of anyone that's tried it in a glider, but it's the one I'd
get if I had Udo's problem. Of course, the converter would only be used
to power the radio, not the other instruments.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Eric Greenwell

October 7th 05, 02:36 AM

David Kinsell wrote:

> The truth is virtually no aircraft radios have upconverters built into
> them. They switch high currents at high voltage at low RF frequencies.
> A nasty thing to be building into a radio with a sensitive receiver. The
> converters put out harmonics from their high-power square waves going
> well into the aircraft band.

I hadn't thought about the noise problem, but I can see it would be an
issue. If they don't use converters, how do the newer radios manage so
well on low voltages? For example, the Becker AR4201 is specified for >2
watts output at 10 volts, and the Dittel FSG 2T is specified from 11 to
16 volts, with 9 to 11 volts emergency operation. Too bad the
Becker/Dittel engineers don't follow ras, but it does free them to
design more stuff for us.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Jim Vincent

October 7th 05, 06:48 PM

"Eric Greenwell" > wrote in message
...
> Jim Vincent wrote:
>> "Andy" > wrote in message
>> oups.com...
>>
>>>If the battery is near death will it provide the current required by
>>>the upconverter? It's not magic and you can't get more power out of
>>>the upconverter than you put in. I'm curious to know if you have
>>>measured the performance with a "battery near death"?
>
> snip
>
>>
>> Haven't tested near death, but actually was part of the thinking. If the
>> battery is near death, it has a little juice left. If the radio would
>> not tolerate a low voltage, then I could upconvert.
>
> This is an interesting idea. By using 12 volts until the radio is close to
> unsatisfactory operation, you avoid the efficiency losses in the
> converter. At that voltage, you switch on the converter and make available
> the rest of the battery's capacity, though with a 10%-15% capacity loss in
> the converter. Still, you'd get 90+% of the battery's capacity, instead of
> 50% (or wherever your radio becomes unsatisfactory).
>
> This might be a solution for Udo, the original poster. I suggest he try
> the Datel converter (UHE-15/2000-Q12) mentioned by Tom Seim, as it is
> cheap, very small, totally enclosed, wide temperature range, and with
> excellent specifications for regulation, ripple, and overload/overvoltage
> protection. I can't guarantee it will work since I don't know of anyone
> that's tried it in a glider, but it's the one I'd get if I had Udo's
> problem. Of course, the converter would only be used to power the radio,
> not the other instruments.
>
> --
> Change "netto" to "net" to email me directly
>
> Eric Greenwell
> Washington State
> USA

I'm a little concerned about hitting the system with 15V. Be sure to check
the voltage operating ranges of all your gear. If you find you're
constrained to a lower voltage, you then have two options. First, get the 15
V model and use the trim function to bring it down by 5% to 14.25 V or
secondly use a 12 V model trimmed up to by 5% to 12.6 V. The trim is easily
configured using resistors or potentiometers.

Eric Greenwell

October 7th 05, 08:49 PM

Jim Vincent wrote:

>>This might be a solution for Udo, the original poster. I suggest he try
>>the Datel converter (UHE-15/2000-Q12) mentioned by Tom Seim, as it is
>>cheap, very small, totally enclosed, wide temperature range, and with
>>excellent specifications for regulation, ripple, and overload/overvoltage
>>protection. I can't guarantee it will work since I don't know of anyone
>>that's tried it in a glider, but it's the one I'd get if I had Udo's
>>problem. Of course, the converter would only be used to power the radio,
>>not the other instruments.

>
> I'm a little concerned about hitting the system with 15V. Be sure to check
> the voltage operating ranges of all your gear. If you find you're
> constrained to a lower voltage, you then have two options. First, get the 15
> V model and use the trim function to bring it down by 5% to 14.25 V or
> secondly use a 12 V model trimmed up to by 5% to 12.6 V. The trim is easily
> configured using resistors or potentiometers.

Yes, 14.25 should be fine, since a fully charged 14 volt battery is
almost 15 volts.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

David Kinsell

October 8th 05, 05:14 AM

Eric Greenwell wrote:
> David Kinsell wrote:
>
>> The truth is virtually no aircraft radios have upconverters built into
>> them. They switch high currents at high voltage at low RF
>> frequencies. A nasty thing to be building into a radio with a
>> sensitive receiver. The converters put out harmonics from their
>> high-power square waves going
> > well into the aircraft band.
>
> I hadn't thought about the noise problem, but I can see it would be an
> issue. If they don't use converters, how do the newer radios manage so
> well on low voltages? For example, the Becker AR4201 is specified for >2
> watts output at 10 volts,

I don't know where you saw that. On their web site, they list the input
voltage as 12.4 to 15.1 volts, with emergency operation only down to 10
volts.

> and the Dittel FSG 2T is specified from 11 to
> 16 volts, with 9 to 11 volts emergency operation.

Yep. In their literature, they also say you must have at least 11.0
volts during transmit.

Sounds like two radios designed for 14 volt operation, just like always.
I wonder how long a 12 volt battery mounted in the tail is going to
supply 12.4 volts to the Becker?? 10 minutes maybe, if you've got good
wiring?? I expect Becker is just a little more honest with their specs,
rather than really being different than the Dittel.

> Too bad the
> Becker/Dittel engineers don't follow ras, but it does free them to
> design more stuff for us.

You've got to keep in mind the soaring market is peanuts compared to
the power market, so that's why radios have been, and still today are
designed to the 14 volt standard. Why put a switching converter in
a radio that's sitting there all day long with a well-regulated, very
stout 14.2 volt supply?

-Dave

David Kinsell

October 8th 05, 05:32 AM

Paul Remde wrote:
> Hi,
>
> It is my belief that all the work required to make an "upconverter" will
> lead to only minimal increases in your radios transmit power (10 to 20%?).
> It doesn't seem worth it to me. I vote 12V.
>
> Paul Remde
>

10-20%??? A discharged 12 volt battery is going to be around 10.5 volts,
with maybe half a volt lost in the wiring and fuses. The upconverter can
comfortably be set to 15 volts. The RF voltage follows the supply, so
it'll be 50% higher. Since the power is the square of the voltage, you're
looking at more than double the transmit power.

But the power isn't the big issue, it's the distortion you get at lower
voltage. Many radios sound really bad on transmit at 11 volts, and shut
down entirely at about 10 volts. Since they're 14 volt radios, that shouldn't
be surprising, should it? I just wish glider pilots had to listen to their
own transmissions, there's some really bad sounding radios on the air.

Upconverters aren't a bad idea, except for the potential for interference in
the cockpit. It's kind of a silly misuse of technology to be using something
like this, when it's so easy to get the proper voltage from a battery. I've
got nothing against them, I've designed them into commercial products where
appropriate, but this just isn't the best place for them.

-Dave

David Kinsell

October 8th 05, 05:38 AM

Andy wrote:
> It's probably also worth noting that a 14volt pack hot off the charger
> has a terminal voltage greater than 15 volts and will exceed the
> maximum voltage specs for many modern glider systems.
>
> Andy
>

Maybe for a few minutes, if you take it off the charger and run to
the plane and immediately install it and turn it on. I've never
seen more than 14.8 volts with a more normal installation.

If you read your manuals, avionics have max voltages of 16 or 16.5
volts, so it doesn't seem to be an issue.

-Dave

Eric Greenwell

October 8th 05, 06:34 AM

David Kinsell wrote:

>> I hadn't thought about the noise problem, but I can see it would be an
>> issue. If they don't use converters, how do the newer radios manage so
>> well on low voltages? For example, the Becker AR4201 is specified for
>> >2 watts output at 10 volts,
>
>
> I don't know where you saw that. On their web site, they list the input
> voltage as 12.4 to 15.1 volts, with emergency operation only down to 10
> volts.

It's in the manual, page 1-3.

>> and the Dittel FSG 2T is specified from 11 to 16 volts, with 9 to 11
>> volts emergency operation.
>
>
> Yep. In their literature, they also say you must have at least 11.0
> volts during transmit.

A 12 volt battery can put out 11 volts.

>
> Sounds like two radios designed for 14 volt operation, just like always.

Not "just like always": The older radios can't come close to the specs
for these radios.

> I wonder how long a 12 volt battery mounted in the tail is going to
> supply 12.4 volts to the Becker?? 10 minutes maybe, if you've got good
> wiring?? I expect Becker is just a little more honest with their specs,
> rather than really being different than the Dittel.
>
>
>> Too bad the Becker/Dittel engineers don't follow ras, but it does free
>> them to design more stuff for us.
>
>
> You've got to keep in mind the soaring market is peanuts compared to
> the power market, so that's why radios have been, and still today are
> designed to the 14 volt standard.

Except handhelds, of course, of which tons are sold. Maybe some of that
design technology is creeping into the panel mounts.

> Why put a switching converter in
> a radio that's sitting there all day long with a well-regulated, very
> stout 14.2 volt supply?

Because it's easy to do? Because the generator might quit? Because you
can sell a few more radios to folks like us? I keep hoping an engineer
with some detail design knowledge of these radios will hop in here and
tell us, but no luck yet.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Tim Mara

October 8th 05, 04:55 PM

Actually.the Walter Dittel FSG2T and previous models FSG70/71 do in fact
have some more sophisticated circuitry that does allow it to operate at a
lower voltage than the Becker does and both are a bit more sophisticated
than others like Avionic Dittel, Filser and Microairs (just to name a few).
Any of these radios will operate at lower voltages at some reduction in TX
output power.but all have more than enough Tx power for our purposes
anyway....you will notice at very low voltages microphone audio becoming
distorted as a first indication that the input voltage has depleted too far
and though at this point it's already too low a battery capacity and will
soon become worthless anyway.......and at that point only PFM would allow it
to function acceptably, it becomes rather relative.no battery left..no radio
tim

Wings & Wheels
www.wingsandwheels.com

"David Kinsell" > wrote in message
...
> Eric Greenwell wrote:
>> David Kinsell wrote:
>>
>>> The truth is virtually no aircraft radios have upconverters built into
>>> them. They switch high currents at high voltage at low RF frequencies.
>>> A nasty thing to be building into a radio with a sensitive receiver.
>>> The converters put out harmonics from their high-power square waves
>>> going
>> > well into the aircraft band.
>>
>> I hadn't thought about the noise problem, but I can see it would be an
>> issue. If they don't use converters, how do the newer radios manage so
>> well on low voltages? For example, the Becker AR4201 is specified for >2
>> watts output at 10 volts,
>
> I don't know where you saw that. On their web site, they list the input
> voltage as 12.4 to 15.1 volts, with emergency operation only down to 10
> volts.
>
>
>> and the Dittel FSG 2T is specified from 11 to 16 volts, with 9 to 11
>> volts emergency operation.
>
> Yep. In their literature, they also say you must have at least 11.0
> volts during transmit.
>
> Sounds like two radios designed for 14 volt operation, just like always.
> I wonder how long a 12 volt battery mounted in the tail is going to
> supply 12.4 volts to the Becker?? 10 minutes maybe, if you've got good
> wiring?? I expect Becker is just a little more honest with their specs,
> rather than really being different than the Dittel.
>
>
>> Too bad the Becker/Dittel engineers don't follow ras, but it does free
>> them to design more stuff for us.
>
> You've got to keep in mind the soaring market is peanuts compared to
> the power market, so that's why radios have been, and still today are
> designed to the 14 volt standard. Why put a switching converter in
> a radio that's sitting there all day long with a well-regulated, very
> stout 14.2 volt supply?
>
> -Dave
>
>

HL Falbaum

October 8th 05, 11:02 PM

As an aside--I have a Dittel FSG71M in the portable base station case(the PS
model) with battery and charger built in. It works very nicely. It has a 12v
7.5 ah battery---factory designed and integrated. This is a "spare no
expense" outfit and I think the Dittel engineers would make it any voltage
they wanted.

--
Hartley Falbaum
"Tim Mara" > wrote in message
...
> Actually.the Walter Dittel FSG2T and previous models FSG70/71 do in fact
> have some more sophisticated circuitry that does allow it to operate at a
> lower voltage than the Becker does and both are a bit more sophisticated
> than others like Avionic Dittel, Filser and Microairs (just to name a
> few). Any of these radios will operate at lower voltages at some reduction
> in TX output power.but all have more than enough Tx power for our purposes
> anyway....you will notice at very low voltages microphone audio becoming
> distorted as a first indication that the input voltage has depleted too
> far and though at this point it's already too low a battery capacity and
> will soon become worthless anyway.......and at that point only PFM would
> allow it to function acceptably, it becomes rather relative.no battery
> left..no radio
> tim
>
> Wings & Wheels
> www.wingsandwheels.com
>
>
> "David Kinsell" > wrote in message
> ...
>> Eric Greenwell wrote:
>>> David Kinsell wrote:
>>>
>>>> The truth is virtually no aircraft radios have upconverters built into
>>>> them. They switch high currents at high voltage at low RF frequencies.
>>>> A nasty thing to be building into a radio with a sensitive receiver.
>>>> The converters put out harmonics from their high-power square waves
>>>> going
>>> > well into the aircraft band.
>>>
>>> I hadn't thought about the noise problem, but I can see it would be an
>>> issue. If they don't use converters, how do the newer radios manage so
>>> well on low voltages? For example, the Becker AR4201 is specified for >2
>>> watts output at 10 volts,
>>
>> I don't know where you saw that. On their web site, they list the input
>> voltage as 12.4 to 15.1 volts, with emergency operation only down to 10
>> volts.
>>
>>
>>> and the Dittel FSG 2T is specified from 11 to 16 volts, with 9 to 11
>>> volts emergency operation.
>>
>> Yep. In their literature, they also say you must have at least 11.0
>> volts during transmit.
>>
>> Sounds like two radios designed for 14 volt operation, just like always.
>> I wonder how long a 12 volt battery mounted in the tail is going to
>> supply 12.4 volts to the Becker?? 10 minutes maybe, if you've got good
>> wiring?? I expect Becker is just a little more honest with their specs,
>> rather than really being different than the Dittel.
>>
>>
>>> Too bad the Becker/Dittel engineers don't follow ras, but it does free
>>> them to design more stuff for us.
>>
>> You've got to keep in mind the soaring market is peanuts compared to
>> the power market, so that's why radios have been, and still today are
>> designed to the 14 volt standard. Why put a switching converter in
>> a radio that's sitting there all day long with a well-regulated, very
>> stout 14.2 volt supply?
>>
>> -Dave
>>
>>
>
>

[email protected]

October 14th 05, 04:19 PM

T o d d P a t t i s t > writes:

> Other advantages are that you can run the battery longer before it
> gets too low, and for any switchmode DC-DC downconverters, such as I
> use for my IPAQ's 5 volt requirements, you get less current draw and
> the battery lasts longer (which it should since you've got more
> stored energy). For me, the advantages of 14 volts outweigh the
> disadvantages on my primary battery (it fits into the space
> available), but not for my backup battery (the larger 14 volt
> battery won't fit there.)

Switch mode converters have a gotcha built in; they are a constant
POWER device. When the voltage drops, they pull more current. If the
wiring resistance being too high is the cause of the low voltage, it
can get ugly very fast, and blow fuses.

--
Paul Repacholi 1 Crescent Rd.,
+61 (08) 9257-1001 Kalamunda.
West Australia 6076
comp.os.vms,- The Older, Grumpier Slashdot
Raw, Cooked or Well-done, it's all half baked.
EPIC, The Architecture of the future, always has been, always will be.

David Kinsell

October 15th 05, 04:54 PM

wrote:
> T o d d P a t t i s t > writes:
>
>> Other advantages are that you can run the battery longer before it
>> gets too low, and for any switchmode DC-DC downconverters, such as I
>> use for my IPAQ's 5 volt requirements, you get less current draw and
>> the battery lasts longer (which it should since you've got more
>> stored energy). For me, the advantages of 14 volts outweigh the
>> disadvantages on my primary battery (it fits into the space
>> available), but not for my backup battery (the larger 14 volt
>> battery won't fit there.)
>
> Switch mode converters have a gotcha built in; they are a constant
> POWER device. When the voltage drops, they pull more current. If the
> wiring resistance being too high is the cause of the low voltage, it
> can get ugly very fast, and blow fuses.
>

That would take some grossly defective wiring. Perhaps a blown fuse would
be the wakeup call needed to fix the problem.

A more credible problem is a weak battery getting deep discharged because
of that. If a radio manufacturer were to actually build one of these
things in, they'd likely turn off the unit at some voltage, rather than
just letting it drag the battery down. But since they're concentrating
on the power market, that's not going to happen.

-Dave

David Kinsell

October 21st 05, 03:21 PM

Eric Greenwell wrote:
> Udo Rumpf wrote:
>
>>> It's possible you have a problem not related to the voltage; e.g.,
>>> maybe the voltage is dropping well below the 11.8 volts when the
>>> transmitter is keyed, or the radio is not functioning within
>>> specifications.
>>> Eric Greenwell
>>
>>
>> I have a 720A Dittle radio
>> Power requirements;
>> Receive .1 - .4 amps
>> Transmit (tone) 1.4 amps (.8 amps unmodulated)
>> The 11.8 volts I was referring to is before transmit.
>> If I remember correctly when the battery is fully charged
>> and I hit the transmit button the voltage drops from 12.7 to 12.2.
>> Udo
>
> With the battery run down to 11.8 volts, measure the voltage right at
> the radio connector while keying the transmitter for 5-10 seconds. If it
> drops more than it does when the battery is fully (or nearly so)
> charged, the problem might be the battery.
>
> However....
> I found a German manual for the ATR720A (and ATR70C in English) on the
> Filser site (I think they took over the radios from Avionic Dittel). The
> specifications don't make any mention of what voltage range the radio
> will function over, so I suspect 12 volt battery operation wasn't on
> their minds when it was designed. This appears to be an older design
> radio, and likely is one that would benefit from 14 volt operation.

Absolutely true. But if you look hard enough, you'll see Filser claims
10.5 to 16 volts as an input voltage range for this radio. The same or
better as the current generation of super radios, which according to the
experts on RAS, supposedly were redesigned to work on lower voltage.

> So, if it's not the battery, your choices seem to be a modern radio
> (like the Walter Dittel FSG 2T I mentioned) or going to a 14 volt
> battery pack. Or waiting till you get closer to the airfield to make
> your call :^)
>

Or, he could get three or four large 12 volt batteries, and keep switching
between them, like a lot of people do. Certainly works for a while.
Particularly if you swap out batteries every year or two so you're using
only really fresh ones.

The FSG 2T very specifically says don't try to transmit with less than 11
volts, so I think that would be an expensive option that really wouldn't
help out. I suppose he could get a new Becker, but it's supposed to have
have at least 12.4 volts. Wonder where all these new super-radios are that
people keep talking about???? When you look at the facts, they just turn
out to be figments of some rather active imaginations.

-Dave

Andy

October 21st 05, 05:54 PM

Microair M760 Transceiver.

"Input Voltage 10 - 16 Volts Warning damage will occur above 16
Volts"

"The operator should remember that the minimum operating voltage is 10
volts. This is the loaded voltage (ie the voltage when the radio is
transmitting). For battery operators, check the battery voltage level,
then press the PTT briefly to note the voltage drop. If the voltage
dips by more than 0.5 volts, change the battery before flying."

I enjoy my active imagination but I can also read a spec sheet.

Eric Greenwell

October 21st 05, 07:40 PM

David Kinsell wrote:

> The FSG 2T very specifically says don't try to transmit with less
> than 11 volts, so I think that would be an expensive option that
> really wouldn't help out.

Contrary to what Dave writes, here is what the FSG 2T operation manual
says on page 50 of the FSG 2T Installation and Operation manual,
available on Wings&Wheels or Dittel's web site:

> 6.13 Emegency Operation
>
> Without degradation the FSG 2T can be operated on a dc source between
> 11 Vdc and nearly 9 volts. This however will NOT reduce the TX
> output level, RX sensitivity, and audio output power, due to internal
> supply regulation. Below 11 volts the dc indicator flashes
> continuously as low supply warning. Since the current drawn from the
> battery will increase with lowered Dc supply voltage, the automatic
> shut-down will speed-up.
>
> If the supply voltage drops below 9 Vdc the FSG 2T swithces OFF
> itself. This automatic feature avoids battery damage due to deep
> discharging, even if the radio is left switched ON for months! This
> is true for all types of 12 Vdc batteries.
>
> If the battery recovers and voltage exceeds approximately 10.5 Vdc,
> the radio returns to operation with the last used setting.

The above clearly shows why pilots have good experiences with Dittel
radios operating on 12 volt battery systems.

> I suppose he could get a new Becker, but it's supposed to have have
> at least 12.4 volts. Wonder where all these new super-radios are
> that people keep talking about???? When you look at the facts, they
> just turn out to be figments of some rather active imaginations.

I think I have found the explanation for the super-radios that we have
today. I stumbled across this reference recently:

> Here’s the operating voltage matrix right out of DO-160 . . .

> Voltage Category B
>
> Maximum 15.1
> Nominal 13.8
> Minimum 11.0
> Emergency 9.0

> Modern avionics should operate over the voltage ranges cited for each
> category of performance commensurate with the applicable system
> voltage.

The table shows operation from 11.0 volts to 15.1, with emergency
operation down to 9 volts, essentially what the Becker and Dittel radios
(and probably others) specify. My short Google search for the standard
came up with an index

http://www.tuvamerica.com/industry/aerospace/emctest.cfm

and this

http://www.aeroelectric.com/articles/do160.html

that shows this specification is just one of many in the standard. I
don't know when the standard came into being, but I'm guessing it (or
the rationale behind it) is what drives manufacturers to produce radios
with a wide voltage tolerance. It's been around for a long time, as the
Dittel FSG 60 manual (March 1981) references the standard.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

David Kinsell

October 27th 05, 02:41 PM

Andy wrote:
> Microair M760 Transceiver.
>
> "Input Voltage 10 - 16 Volts Warning damage will occur above 16
> Volts"
>
> "The operator should remember that the minimum operating voltage is 10
> volts. This is the loaded voltage (ie the voltage when the radio is
> transmitting). For battery operators, check the battery voltage level,
> then press the PTT briefly to note the voltage drop. If the voltage
> dips by more than 0.5 volts, change the battery before flying."
>
> I enjoy my active imagination but I can also read a spec sheet.
>

You must have missed the part where it says "Input Voltage: Normal 13.8 Volts"
and "Emergency Min: 10.7"

http://www.microair.com.au/admin/uploads/M760VHFdatasheet190905.pdf

The 10.7 emergency min was quoted for all revs of the radio up through
rev M.

The "Normal" 13.8 is what most people call Nominal. It's the only voltage
where the specs on power, distortion, etc are valid.

It's funny you should trot out the Microair as an example of some great
new radio supposed designed for 12 volt operation. In reality, it's been
one of the worst performers at low voltage transmit operation, regardless
of what the specs say.

It's just another radio designed for 14 volt operation, which works poorly
at low voltage, particularly on transmit. Same as we've had for at least
the last 20 years. Quoting specs of 10-16 volts with 13.8 nominal isn't
what I'd call news.

-Dave

David Kinsell

October 27th 05, 02:57 PM

Eric Greenwell wrote:
> David Kinsell wrote:
>
>> The FSG 2T very specifically says don't try to transmit with less than
>> 11 volts, so I think that would be an expensive option that really
>> wouldn't help out.
>
> Contrary to what Dave writes, here is what the FSG 2T operation manual
> says on page 50 of the FSG 2T Installation and Operation manual,
> available on Wings&Wheels or Dittel's web site:
>

Utter baloney. The brochure for the radio, also available at the
W&W site, says:

"Is onboard supply sufficient? Observe onboard supply indicator
particularly during transmit, at least 11.0 Vdc must be shown!"

http://www.wingsandwheels.com/FSG2T%20Brouchure.pdf

[email protected]

October 27th 05, 08:47 PM

Exactly which part is utter baloney; the manual or the brochure?

Tom

Eric Greenwell

October 27th 05, 11:12 PM

David Kinsell wrote:
> Eric Greenwell wrote:
>
>> David Kinsell wrote:
>>
>>> The FSG 2T very specifically says don't try to transmit with less
>>> than 11 volts, so I think that would be an expensive option that
>>> really wouldn't help out.
>>
>>
>> Contrary to what Dave writes, here is what the FSG 2T operation
>> manual says on page 50 of the FSG 2T Installation and Operation
>> manual, available on Wings&Wheels or Dittel's web site:
>>
>> 6.13 Emegency Operation
>>
>> Without degradation the FSG 2T can be operated on a dc source
>> between
>> 11 Vdc and nearly 9 volts. This however will NOT reduce the TX output
>> level, RX sensitivity, and audio output power, due to internal supply
>> regulation. Below 11 volts the dc indicator flashes continuously as
>> low supply warning. Since the current drawn from the battery will
>> increase with lowered Dc supply voltage, the automatic shut-down will
>> speed-up.
>>
>> If the supply voltage drops below 9 Vdc the FSG 2T swithces OFF
>> itself. This automatic feature avoids battery damage due to deep
>> discharging, even if the radio is left switched ON for months! This
>> is true for all types of 12 Vdc batteries.
>>
>> If the battery recovers and voltage exceeds approximately 10.5 Vdc,
>> the radio returns to operation with the last used setting.

>
> Utter baloney. The brochure for the radio, also available at the W&W
> site, says:
>
> "Is onboard supply sufficient? Observe onboard supply indicator
> particularly during transmit, at least 11.0 Vdc must be shown!"

http://www.wingsandwheels.com/FSG2T%20Brouchure.pdf

Interested pilots should read the rest of the brochure. What Dave is
referring to is the section that begins:

"Function Checks:
If the Transceiver FSG 2T does not operate correctly, check the following:"

This is a trouble shooting section, not a normal operation section.
Making sure the pilot is using a battery with sufficient charge to test
the radio is very sensible, and a battery with less than 11 volt under
load is nearly exhausted, or there is a high resistance in the wiring or
the battery.

The Technical Data section of this brochure includes the specification:

"RF Output: >= 5W into 50 ohms (carrier power), >= 18 W (PEP) @ 9 to 16
VDC."

This is the same as the manual. I don't see how it can be stated any
more clearly that this radio will function at full power down to 9
volts. It does not mean your radio will be able to transmit with a 12
volt battery that only has 9 volts left on it. The FSG 2T manual makes
this clear, and has a table with estimated times of operation as your
battery discharges below 11 volts. How low the battery voltage can go
and still allow you to transmit depends very much on the size and
condition of your battery.

Question: Why do Dittel, Becker, and Filser have such broad input
operating voltage ranges?

Answer: "These voltages ranges are a European requirement" - Eric
Pscherer, Dittel engineer, in a recent phone call to me. Further, he
stated the new requirement is now 9.1 volts to 16.1 volts, and that
these ranges are easy to achieve with the power supplies now available.
In the past, he said, switching supplies were too noisy (electrically)
to use in receivers, but that is not the case now.

Question: What are the European requirements?

Answer: The requirements for voltage range and many others parameters
are contained in the RTCA/DO-160E document, "Environmental Conditions
and Test Procedures for Airborne Equipment", published by RTCA, Inc., in
Washington, DC. Anoraks will want to peruse this large (778 page, 20 MB
pdf file!) and mind-numbing document, a 2004 draft of which may be
downloaded here (found by Tom Seim):

http://pr.erau.edu/~lyallj/SC135/D-to-E.pdf

or you can purchase a copy of the current document from RTCA for a few
hundred dollars. Incidentally, the document covers far more than just
radios.

The voltage range section for Category B, which our radios fit into, is
in 16.6.1 (Normal Range), and a few pages down you will find the
values for Abnormal Range.

What it means for glider pilots is our European radios are designed to
operate properly on a 12 volt battery, even one that is essentially
exhausted. Motorglider pilots will be delighted to know the standard has
stringent requirements for withstanding voltage surges produced by
engine driven generating systems, and starting their engine with the
radios on (the usual case during an in-air restart, at least for me!) is
very unlikely to cause any damage.

Question: Why the heck does DO-160D ask for such a voltage range when
the radio will be operating on 13.8 volts all the time?

Answer: I can only guess that it is to ensure operation in situations
where the generating system has malfunctioned (alternator gone bad,
drive belt broken, etc) and the battery, or a much smaller backup power
source, has to supply power. Airplane pilots tend to be very dependent
on their radios and other instruments, and someone flying IFR is not
going to be happy if the instrument quits before the battery does.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Paul Remde

October 27th 05, 11:18 PM

Hi Eric,

Excellent research and presentation of pertinent data!

Thanks,

Paul Remde

"Eric Greenwell" > wrote in message
...
> David Kinsell wrote:
>> Eric Greenwell wrote:
>>
>>> David Kinsell wrote:
>>>
>>>> The FSG 2T very specifically says don't try to transmit with less
>>>> than 11 volts, so I think that would be an expensive option that
>>>> really wouldn't help out.
>>>
>>>
>>> Contrary to what Dave writes, here is what the FSG 2T operation
>>> manual says on page 50 of the FSG 2T Installation and Operation
>>> manual, available on Wings&Wheels or Dittel's web site:
>>>
>>> 6.13 Emegency Operation
>>>
>>> Without degradation the FSG 2T can be operated on a dc source
>>> between
>>> 11 Vdc and nearly 9 volts. This however will NOT reduce the TX output
>>> level, RX sensitivity, and audio output power, due to internal supply
>>> regulation. Below 11 volts the dc indicator flashes continuously as
>>> low supply warning. Since the current drawn from the battery will
>>> increase with lowered Dc supply voltage, the automatic shut-down will
>>> speed-up.
>>>
>>> If the supply voltage drops below 9 Vdc the FSG 2T swithces OFF
>>> itself. This automatic feature avoids battery damage due to deep
>>> discharging, even if the radio is left switched ON for months! This
>>> is true for all types of 12 Vdc batteries.
>>>
>>> If the battery recovers and voltage exceeds approximately 10.5 Vdc,
>>> the radio returns to operation with the last used setting.
>
>
>>
>> Utter baloney. The brochure for the radio, also available at the W&W
>> site, says:
>>
>> "Is onboard supply sufficient? Observe onboard supply indicator
>> particularly during transmit, at least 11.0 Vdc must be shown!"
>
> http://www.wingsandwheels.com/FSG2T%20Brouchure.pdf
>
> Interested pilots should read the rest of the brochure. What Dave is
> referring to is the section that begins:
>
> "Function Checks:
> If the Transceiver FSG 2T does not operate correctly, check the
> following:"
>
> This is a trouble shooting section, not a normal operation section. Making
> sure the pilot is using a battery with sufficient charge to test the radio
> is very sensible, and a battery with less than 11 volt under load is
> nearly exhausted, or there is a high resistance in the wiring or the
> battery.
>
> The Technical Data section of this brochure includes the specification:
>
> "RF Output: >= 5W into 50 ohms (carrier power), >= 18 W (PEP) @ 9 to 16
> VDC."
>
> This is the same as the manual. I don't see how it can be stated any more
> clearly that this radio will function at full power down to 9 volts. It
> does not mean your radio will be able to transmit with a 12 volt battery
> that only has 9 volts left on it. The FSG 2T manual makes this clear, and
> has a table with estimated times of operation as your battery discharges
> below 11 volts. How low the battery voltage can go and still allow you to
> transmit depends very much on the size and condition of your battery.
>
> Question: Why do Dittel, Becker, and Filser have such broad input
> operating voltage ranges?
>
> Answer: "These voltages ranges are a European requirement" - Eric
> Pscherer, Dittel engineer, in a recent phone call to me. Further, he
> stated the new requirement is now 9.1 volts to 16.1 volts, and that these
> ranges are easy to achieve with the power supplies now available. In the
> past, he said, switching supplies were too noisy (electrically) to use in
> receivers, but that is not the case now.
>
> Question: What are the European requirements?
>
> Answer: The requirements for voltage range and many others parameters are
> contained in the RTCA/DO-160E document, "Environmental Conditions and Test
> Procedures for Airborne Equipment", published by RTCA, Inc., in
> Washington, DC. Anoraks will want to peruse this large (778 page, 20 MB
> pdf file!) and mind-numbing document, a 2004 draft of which may be
> downloaded here (found by Tom Seim):
>
> http://pr.erau.edu/~lyallj/SC135/D-to-E.pdf
>
> or you can purchase a copy of the current document from RTCA for a few
> hundred dollars. Incidentally, the document covers far more than just
> radios.
>
> The voltage range section for Category B, which our radios fit into, is in
> 16.6.1 (Normal Range), and a few pages down you will find the values for
> Abnormal Range.
>
> What it means for glider pilots is our European radios are designed to
> operate properly on a 12 volt battery, even one that is essentially
> exhausted. Motorglider pilots will be delighted to know the standard has
> stringent requirements for withstanding voltage surges produced by engine
> driven generating systems, and starting their engine with the radios on
> (the usual case during an in-air restart, at least for me!) is very
> unlikely to cause any damage.
>
> Question: Why the heck does DO-160D ask for such a voltage range when the
> radio will be operating on 13.8 volts all the time?
>
> Answer: I can only guess that it is to ensure operation in situations
> where the generating system has malfunctioned (alternator gone bad, drive
> belt broken, etc) and the battery, or a much smaller backup power source,
> has to supply power. Airplane pilots tend to be very dependent on their
> radios and other instruments, and someone flying IFR is not going to be
> happy if the instrument quits before the battery does.
>
> --
> Change "netto" to "net" to email me directly
>
> Eric Greenwell
> Washington State
> USA