Hand Held Radios (Com + Nav)and GPS...Help?

Morgans wrote:

NiMH have a self-discharge rate of 3-5% per day. If you are going on
extended trips, purchase an alkaline battery pack.


You need to google about that to see for yourself. They self discharge at
slightly over 1% per day.

Agreed, but the self-discharge rate can increase as the cells age.

Given the fact that they have a higher capacity
than alkaline, they will still have more capacity left over, even
considering self discharge, than alkalines for at least two or three weeks.

The relative capacity of alkalines and NiMH cells depends on how large the
current draw is. For AA cells, alkalines are typically rated to have a
capacity of about 2800 mA-hr which is higher than the rating for today's
NiMH of about 2200 mA-hr. However, the 2800 rating for alkalines is tested
at a very low discharge rate of 20 mA and at higher current draws the
effective capacity drops substantially. At a current draw of 1 A (1000
mA), the capacity of alkalines drops to about 750 mA-hr while NiMH cells
are much less affected and still deliver almost their rated capacity. So
for low-power devices the alkaline cells still outlive a single charge of
the NiMH cells, but for higher-power devices the NiMH cells last much longer.

In the case of a communications radio it depends on how it's used - if only
used to receive I'd expect the alkalines to do better but if frequently
used to transmit (i.e. higher power) then the NiMH cells will last longer.

Even if the alkalines might last longer than a single charge of the NiMH,
I'd usually still use the rechargeable NiMH for the lower long-term cost.
But a spare set of alkalines (or even better Li) cells is good for backup
since they have such good storage characteristics.

I may go with the Icom A5 and save a $100,
as in my experience, the nav feature on the IC-A22 has limited range
and usefulness, (at least with the supplied antenna).

I've been considering buying a handheld radio. A couple of weeks
ago in absolutely perfect weather, the radios in the FBO's plane
were being intermittant. Although no emergency, it helped me
decide I want a radio especially since I've started my IFR
training.

After some research, it was a toss up between the Vertex
with a few more gizmos and NiCd cells or the ICOM A5
with NiMH cells. Both were withing $30 or so from
various places since ICOM was offering a few
headset adapter for the A5 that was included with the Vertex.
Well I found LC Flight (www.lcflight.com) had the same
price as most other discount shops and was offering
a FREE alkaline battery pack for the A5. It came to $280
with the headset adapter from ICOM and the alkaline battery
case from LCFlight + 6 S/H. I haven't gotten it yet but it
will probably get here on Monday.

I ordered from them once before and they were quite on
par with Sportys. I ended up dealing with them more than
I wanted to as the DC 10-60's they sent to me had a very
short cable between the two ear cups so they couldn't
be extended far enough. I ended up sending it back for a refund
minus the shipping and was minimal hassle.

(and no, I do not have any affiliation with them).

Gerald

I used to have the top of the line Yaesu with all the accessories.

It disappeared a year or so ago and I replaced it with an Icom, a
simpler com only that only has a AA battery pack, though rechargable
cells are avaiable for it. It cost about half as much as I originally
paid for the Yaesu. I don't think it has much transmission range from
inside the cockpit with just its little rubber duckie antenna, but it
receives well and picks up NOAA broadcasts too.

My experience with the Yaesu Nav functions were that they were 100%
worthless. I could pick up the VOR with my naked eye before the stupid
little thing would find it. The NiCd cell in the Yaesu would auto-discharge
in about two weeks, making it impractical to leave in a flight bag.

I've also tried navigating with a Sporty's. It worked MUCH better than the
Yaesu. Even with the little rubber ducky antenna, sitting on a Cessna
glare shield it worked almost as well as the panel mount VORs. It's not
as slick a package as either the newest Yaesu or Icom, but performance was
excellent. I do believe I could navigate VOR to VOR and maybe, in an
emergency, even shoot a localizer with just the Sporty's. I've been intending
to try that, but have not so far.

Morgans wrote:
NiMH have a self-discharge rate of 3-5% per day. If you are going on
extended trips, purchase an alkaline battery pack.


You need to google about that to see for yourself. They self discharge at
slightly over 1% per day. Given the fact that they have a higher capacity
than alkaline, they will still have more capacity left over, even
considering self discharge, than alkalines for at least two or three weeks.

I have gone to different sites and read different values, so I use the
highest.

That's not the cleverest plan in the world, is it? Some of the data is ten
years old, and some was done last week.

Ten years ago, it WAS 3% a day. Five years ago, it got down to 2, and now it is
1 and still dropping.

Instead of using the highest, why not use the current data?

Jim



john smith
shared these priceless pearls of wisdom:

-
-I have gone to different sites and read different values, so I use the
-highest.

Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

Jim Weir wrote:
Instead of using the highest, why not use the current data?

So I can more easily figure out if I need to recharge. ;-))

The rechargable was a major reason for switching from a Sporty's to
the Yaseu (aka Vertex) for me.

My handheld is my only radio, so buying AA batts was a real drain for
me. By the same token, I know that if I'm going to be flying for a
couple of hours, I probably should charge up the radio.

For a backup radio, it would be a more difficult call. Why not
recharge on the first day of every month?

On Sun, 22 Feb 2004 00:34:24 -0500, "Morgans"
wrote:



NiMH have a self-discharge rate of 3-5% per day. If you are going on
extended trips, purchase an alkaline battery pack.

You need to google about that to see for yourself. They self discharge at
slightly over 1% per day. Given the fact that they have a higher capacity
than alkaline, they will still have more capacity left over, even
considering self discharge, than alkalines for at least two or three weeks.

- I am the type of person to prepare by charging things often, so it is
ablsolutely no problem for me. If you do prepare for a long trip by
charging, you have around two times the capacity than alkaline, so where is
the down side? Add to that a charger to run off of ship's power, and you
can go long, indefinitely.

all the best -- Dan Ford
email: (requires authentication)

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

Ok....tried it... (the AV demo..
But... only one dealer (in all North America !) listed... and
the link does not work.

Huh??? The AvMap is available through all the big avionics houses.
Pacific Coast Avionics, Gulf Coast Avionics, J.A. Avionics, Sarasota
Avionics -- they all handle the AvMap. They've had a banner year,
according to the folks I've spoken with at AvMap. This only makes sense --
it's twice the unit for only a few hundred dollars more.

Where did you get yours and how much?

I bought mine at OSH '03. We had three avionics places competing for our
buck. Sarasota Avionics won the battle. The price was right around $1700
INCLUDING tax, which is a good deal.

And for what other reasons did you rule out the Lowrance?

Lowrance *had* my business -- I own(ed) an Airmap 300. They lost my future
business when the unit failed after just four years (it stopped recognizing
the airport database card), and they were "no longer" able to repair it.
They were more than "willing" to sell me an Airmap 100 --- with a dinky
screen -- or the 500, which isn't much better.

And the 1000 wasn't available yet.

So, I declined their kind offer, and took my business to AvMap. It's an
awesome unit.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Jay,

the $400 difference paled into insignificance.


It's still not "a few bucks", but rather a cool 25 percent more.

--
Thomas Borchert (EDDH)

It's still not "a few bucks", but rather a cool 25 percent more.

Right. For a 50% larger (and brighter) color screen, and all the instrument
approaches.

And -- more importantly to me -- the obstruction database that Garmin
stupidly omits.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"