PowerFLARM antenna mounts [Archive]

July 4th 12, 08:16 PM

Having a glare-shield mounted antenna is like sitting behind a support column at a basketball game. No matter how hard you try, you are going to miss part of the game.

We seem content at compromising field-of-vision with cockpit reflections, compasses, PowerFlarm units and antennas, and multi-function displays. Yet, uncomprimised field-of-vision is our #1 accident preventer.

PowerFlarmUSA...please find a better antenna solution.

On Wednesday, July 4, 2012 11:50:53 AM UTC-4, Dave Nadler wrote:
> Rex is looking into making glare-shield antenna mounts
> for the PowerFLARM dipole antenna, especially for
> gliders with glare-shields that jettison with the
> canopy (Schleicher, LS). The mount will feature:
> - mast sticks up above glare-shield
> - base mounts underneath glare-shield with velcro
> - anti-glare flat-black finish
> This arrangement permits safe canopy jettison
> and easy canopy removal.
>
> You'll cut a ~ 3-4" round hole in the glare-shield,
> afix the velcro, then stick on the antenna so it
> is vertical in flight attitude (with coax at
> about 45 degrees away from the antenna).
>
> Cost guestimated at $75 including shipping.
>
> Please send Rex an email if you're interested as
> he needs to gauge interest; contact info here:
> http://www.williamssoaring.com
>
> Thanks,
> Best Regards, Dave "YO electric"
>
> PS: If you're interested in a mount for a flat-top
> glare-shield (SH, etc) - send Rex a note.

Dave Nadler

July 5th 12, 04:42 AM

On Wednesday, July 4, 2012 12:16:38 PM UTC-7, (unknown) wrote:
> Having a glare-shield mounted antenna is like sitting behind a support column at a basketball game.

Complete Nonsense. The antenna and any decent
mount are thin, and you won't notice them after
5 minutes. The angle blocked is only slightly
more than your yaw string.

Are you going to remove your yaw string too ?

Really now.

Ramy

July 5th 12, 07:07 AM

On Wednesday, July 4, 2012 8:42:39 PM UTC-7, Dave Nadler wrote:
> On Wednesday, July 4, 2012 12:16:38 PM UTC-7, (unknown) wrote:
> > Having a glare-shield mounted antenna is like sitting behind a support column at a basketball game.
>
> Complete Nonsense. The antenna and any decent
> mount are thin, and you won't notice them after
> 5 minutes. The angle blocked is only slightly
> more than your yaw string.
>
> Are you going to remove your yaw string too ?
>
> Really now.

No doubt PowerFlarm USA can come up with more aesthetic antenna and solutions.
I will have to compromise meanwhile, but am expecting a better solution will followup shortly once they start shipping and have more time.
The pictures I saw so far hurt my eyes...

Ramy (who is eagerly waiting for his brick unit)

John Godfrey (QT)[_2_]

July 5th 12, 12:48 PM

On Wednesday, July 4, 2012 11:50:53 AM UTC-4, Dave Nadler wrote:
> Rex is looking into making glare-shield antenna mounts
> for the PowerFLARM dipole antenna, especially for
> gliders with glare-shields that jettison with the
> canopy (Schleicher, LS). The mount will feature:
> - mast sticks up above glare-shield
> - base mounts underneath glare-shield with velcro
> - anti-glare flat-black finish
> This arrangement permits safe canopy jettison
> and easy canopy removal.
>
> You'll cut a ~ 3-4" round hole in the glare-shield,
> afix the velcro, then stick on the antenna so it
> is vertical in flight attitude (with coax at
> about 45 degrees away from the antenna).
>
> Cost guestimated at $75 including shipping.
>
> Please send Rex an email if you're interested as
> he needs to gauge interest; contact info here:
> http://www.williamssoaring.com
>
> Thanks,
> Best Regards, Dave "YO electric"
>
> PS: If you're interested in a mount for a flat-top
> glare-shield (SH, etc) - send Rex a note.

I'm not an antenna maven (certainly not at GHz frequencies, but we are talking about a device that operates at about the transponder frequencies. Transponder antennas are pieced of straight wire with a ground plane.

Seems to me that it should be possible to craft a very good antenna from a piece of piano wire (read so thin it is virtually invisible) and a (sloped down a bit) ground plane.

Any antenna geeks out there?

QT
Never confuse a graduate engineer with a competent technician...

[email protected]

July 5th 12, 01:27 PM

On Thursday, July 5, 2012 7:48:21 AM UTC-4, John Godfrey (QT) wrote:
> On Wednesday, July 4, 2012 11:50:53 AM UTC-4, Dave Nadler wrote:
> > Rex is looking into making glare-shield antenna mounts
> > for the PowerFLARM dipole antenna, especially for
> > gliders with glare-shields that jettison with the
> > canopy (Schleicher, LS). The mount will feature:
> > - mast sticks up above glare-shield
> > - base mounts underneath glare-shield with velcro
> > - anti-glare flat-black finish
> > This arrangement permits safe canopy jettison
> > and easy canopy removal.
> >
> > You'll cut a ~ 3-4" round hole in the glare-shield,
> > afix the velcro, then stick on the antenna so it
> > is vertical in flight attitude (with coax at
> > about 45 degrees away from the antenna).
> >
> > Cost guestimated at $75 including shipping.
> >
> > Please send Rex an email if you're interested as
> > he needs to gauge interest; contact info here:
> > http://www.williamssoaring.com
> >
> > Thanks,
> > Best Regards, Dave "YO electric"
> >
> > PS: If you're interested in a mount for a flat-top
> > glare-shield (SH, etc) - send Rex a note.
>
> I'm not an antenna maven (certainly not at GHz frequencies, but we are talking about a device that operates at about the transponder frequencies. Transponder antennas are pieced of straight wire with a ground plane.
>
> Seems to me that it should be possible to craft a very good antenna from a piece of piano wire (read so thin it is virtually invisible) and a (sloped down a bit) ground plane.
>
> Any antenna geeks out there?
>
> QT
> Never confuse a graduate engineer with a competent technician...

Antenna QT describes will work for areas above the ground plane.
I believe dipole is being used to provide a better transmission pattern both above and below the glider.
Another voice.
UH

John Godfrey (QT)[_2_]

July 5th 12, 01:34 PM

On Wednesday, July 4, 2012 11:50:53 AM UTC-4, Dave Nadler wrote:
> Rex is looking into making glare-shield antenna mounts
> for the PowerFLARM dipole antenna, especially for
> gliders with glare-shields that jettison with the
> canopy (Schleicher, LS). The mount will feature:
> - mast sticks up above glare-shield
> - base mounts underneath glare-shield with velcro
> - anti-glare flat-black finish
> This arrangement permits safe canopy jettison
> and easy canopy removal.
>
> You'll cut a ~ 3-4" round hole in the glare-shield,
> afix the velcro, then stick on the antenna so it
> is vertical in flight attitude (with coax at
> about 45 degrees away from the antenna).
>
> Cost guestimated at $75 including shipping.
>
> Please send Rex an email if you're interested as
> he needs to gauge interest; contact info here:
> http://www.williamssoaring.com
>
> Thanks,
> Best Regards, Dave "YO electric"
>
> PS: If you're interested in a mount for a flat-top
> glare-shield (SH, etc) - send Rex a note.

Sloped groundplane (like base station antennas) should ensure propagation down to canopy rail angle. Need GHz antenna geek.

John Godfrey (QT)[_2_]

July 5th 12, 01:35 PM

JohnDeRosa

July 5th 12, 02:40 PM

On Jul 4, 10:50*am, Dave Nadler > wrote:

> Rex is looking into making glare-shield antenna mounts
> for the PowerFLARM dipole antenna, especially for
> gliders with glare-shields that jettison with the
> canopy (Schleicher, LS).

If the proposed alternative glare screen antenna mount comes to
fruition, doesn't the coax between the unit and the antenna cause an
impediment to the jettisoning of the canopy? Or is there a breakaway
connection of some sort?

> You'll cut a ~ 3-4" round hole in the glare-shield,
> afix the velcro, then stick on the antenna so it
> is vertical in flight attitude (with coax at
> about 45 degrees away from the antenna).

Out of curiosity, why such a large 3-4" hole? Is that so both
antennas can stick through a single hole? Could you not drill two
smaller holes at the correct spacing? Or do the pictures of the
PowerFlarm I find at your site (which shows two small diameter
antennas) differ from reality and we are now only have one antenna?
Just don't want someone to needlessly emasculate their glare screen!

Thanks, John

JohnDeRosa

July 5th 12, 02:49 PM

Googling "PowerFlarm antenna" I see both two antenna (thin or thick)
and single antenna installations.
But I still don't get the 3-4" hole. Expiring minds want to know.

And then this rather interesting picture of a PowerFlarm "Perfect"
antenna location as mentioned by Craggy Aero. ;-)

http://www.google.com/imgres?hl=en&biw=1260&bih=824&tbm=isch&tbnid=UDYzVuGm_Px_OM:&imgrefurl=http://www.craggyaero.com/powerflarm.htm&docid=WD-HpQL8arS20M&imgurl=http://www.craggyaero.com/4-rc-12-aircraft.jpg&w=500&h=282&ei=3Jn1T8uWIqX62AXc_MyFBw&zoom=1&iact=hc&vpx=167&vpy=166&dur=1146&hovh=168&hovw=299&tx=132&ty=91&sig=108342408121063199253&page=1&tbnh=108&tbnw=192&start=0&ndsp=20&ved=1t:429,r:0,s:0,i:73

Thanks, John

John Cochrane[_2_]

July 5th 12, 03:09 PM

On Jul 5, 8:49*am, JohnDeRosa > wrote:
> Googling "PowerFlarm antenna" I see both two antenna (thin or thick)
> and single antenna installations.
> But I still don't get the 3-4" hole. *Expiring minds want to know.
>
> And then this rather interesting picture of a PowerFlarm "Perfect"
> antenna location as mentioned by Craggy Aero. *;-)
>
> http://www.google.com/imgres?hl=en&biw=1260&bih=824&tbm=isch&tbnid=UD...
>
> Thanks, John

Because the glareshield jettsons with the canopy, and the whole mess
has to stay with the glider, not the canopy. If you feed it through
two holes, you've just permanently attached the canopy to the glider.
This is a BIG no-no. If you can't jettison the canopy, you can't get
out of the glider. This has happened, with pda cables holding the
canopy to the glider.

I understand from Dave Nadler that Flarm has tried lots of the
interesting antenna suggestions from this forum, including the rather
obvious idea of bottom-fed and bottom-mounted dipoles, and found they
don't work well enough. Given that fact, roll your own without
extensive testing is probably not a good idea. (Dave: A list of "here
are the antennas we tried that don't work" might be useful here.) That
also suggests that we not hold our breaths for more aesthetically
pleasing antennas any time soon, but perhaps Dave would rather comment
on that possibility.

John Cochrane

bumper[_4_]

July 5th 12, 05:10 PM

As Dave Nadler says, a vertical antenna "disappears". when focused at infinity - as long as you have two eyeballs and the antenna is dark colored, the brain doesn't pay any attention to it.

As to making the antenna out of very thin wire; from my Nave ET days, a thin antenna element has a more narrow bandwidth. Since flarm uses a frequency hopping protocol (I think from 885 to 915 Mhz), thin may not work very well.

Like Rex Mayes (Williams Soaring), I made the mount for my PF as a shelf that sits just aft and slightly below the glareshield. Power lead goes through a small hole in the top of the glareshield, then through a male to female in-line coaxial plug connector (Amazon - 5.5mm X 2.1mm, commonly used for CCTV) to allow clean canopy jettison. If the canopy goes away it takes the PF with it.

bumper

Tim Taylor

July 5th 12, 05:57 PM

On Jul 5, 12:07*am, Ramy > wrote:
> On Wednesday, July 4, 2012 8:42:39 PM UTC-7, Dave Nadler wrote:
> > On Wednesday, July 4, 2012 12:16:38 PM UTC-7, (unknown) wrote:
> > > Having a glare-shield mounted antenna is like sitting behind a support column at a basketball game.
>
> > Complete Nonsense. The antenna and any decent
> > mount are thin, and you won't notice them after
> > 5 minutes. The angle blocked is only slightly
> > more than your yaw string.
>
> > Are you going to remove your yaw string too ?
>
> > Really now.
>
> No doubt PowerFlarm USA can come up with more aesthetic antenna and solutions.
> I will have to compromise meanwhile, but am expecting a better solution will followup shortly once they start shipping and have more time.
> The pictures I saw so far hurt my eyes...
>
> Ramy (who is eagerly waiting for his brick unit)

I guess I am not sure what you are seeing that is so ugly?

Here is what I see from my cockpit:

https://plus.google.com/photos/108936014984094330632/albums/5761722249435143009/5761722263754238914

I only see about one inch of the PowerFLARM antenna over my compass.

I have flown two nationals with the Brick now. I see aircraft up to
11 miles and could not imagine flying a contest without it. I had a
head on at my altitude alert with a closing speed of over 250 mph at
Parowan with W3. I would have never seen the other glider with the
light angle and speeds we were flying.

The common statement among pilots with PowerFLARM was "I can't believe
anyone would fly without PowerFLARM".

Tim (TT)

Morgan[_2_]

July 5th 12, 07:24 PM

The original post describes how the antenna assembly is attached to the glare shield with velcro. Presumably from underneath with just enough velcro to get the job done, but not impede the jettison process. Knowing the quality of fabrication that Rex and the team does at Williams, I suspect this will be a nice solution for those of us with Schleichers. I'll be ordering one.

On Thursday, July 5, 2012 6:40:47 AM UTC-7, JohnDeRosa wrote:
> On Jul 4, 10:50*am, Dave Nadler > wrote:
>
> > Rex is looking into making glare-shield antenna mounts
> > for the PowerFLARM dipole antenna, especially for
> > gliders with glare-shields that jettison with the
> > canopy (Schleicher, LS).
>
> If the proposed alternative glare screen antenna mount comes to
> fruition, doesn't the coax between the unit and the antenna cause an
> impediment to the jettisoning of the canopy? Or is there a breakaway
> connection of some sort?
>
> > You'll cut a ~ 3-4" round hole in the glare-shield,
> > afix the velcro, then stick on the antenna so it
> > is vertical in flight attitude (with coax at
> > about 45 degrees away from the antenna).
>
> Out of curiosity, why such a large 3-4" hole? Is that so both
> antennas can stick through a single hole? Could you not drill two
> smaller holes at the correct spacing? Or do the pictures of the
> PowerFlarm I find at your site (which shows two small diameter
> antennas) differ from reality and we are now only have one antenna?
> Just don't want someone to needlessly emasculate their glare screen!
>
> Thanks, John

[email protected]

July 6th 12, 12:34 AM

> The common statement among pilots with PowerFLARM was "I can't believe
> anyone would fly without PowerFLARM".

Agree...no arguments. My point is anything protruding into the available plexiglass field-of-vision is not desirable and IMO not acceptable. Example: there appears to be three objects above TT's glare shield base; in a "perfect storm", an aircraft could easily "hide" in the shadow of TT's compass. Splitting hairs? Maybe...but all it takes is missing one thermaling bird or a glint off a wing to change your day from outstanding to average or to DNF or to (God forbid) even worse.

Respected manufactures, please do not recommend application of your products into one's field-of-vision.

Darryl Ramm

July 6th 12, 05:03 AM

On Thursday, July 5, 2012 4:34:34 PM UTC-7, (unknown) wrote:
> > The common statement among pilots with PowerFLARM was "I can't believe
> > anyone would fly without PowerFLARM".
>
> Agree...no arguments. My point is anything protruding into the available plexiglass field-of-vision is not desirable and IMO not acceptable. Example: there appears to be three objects above TT's glare shield base; in a "perfect storm", an aircraft could easily "hide" in the shadow of TT's compass. Splitting hairs? Maybe...but all it takes is missing one thermaling bird or a glint off a wing to change your day from outstanding to average or to DNF or to (God forbid) even worse.
>
> Respected manufactures, please do not recommend application of your products into one's field-of-vision.

"not acceptable" is very subjective and certainly an antenna installed up on the glareshield in return for the benefits of PowerFLARM is more than acceptable to me.

To get reliable, range and operation from PowerFLARM we need to get suitable antennas up high with good line of sight especially forward. They just cannot be buried below typical glareshields, etc. or in many of the other things that show up in the hall of shame. Please lets focusing on getting proper/high quality PowerFLARM installs and less on making a big thing out of something that is not.

Darryl

[email protected]

July 6th 12, 10:43 AM

The human eye focuses at "infinity" from a around three meters on out. I don't think I can get a PowerFlarm antenna that far away from me unless I'm looking at it from the back of a tandem two seater. I mounted a mock up of the portable and its antennas on the glare shield of my ASW-15 and found it very distracting and obstructive (my compass is in the panel and my yaw string is only an inch and a half long and is mounted far forward on the canopy so only the string itself is visible when seated in the glider).

A friend of mine has been trying to purchase a portable for over a month but the dealer told him he wasn't shipping them because he was waiting for a(nother) fix from the manufacturer before selling any. He hasn't been able to get any updates on the situation since the initial contact.

I'm waiting until the brick is out and has gone through several revisions. I don't like the idea of being a retail customer and performing the duties of a beta tester. Whenever I get the brick I'm going to have to either ditch my mechanical vario so I can install the 57mm display or get a new electric vario/computer which can show the Flarm data on its primary display because there's no room left on the panel.

One question I have is if the range is seriously decreased by mounting the antenna at an angle, does banking the glider also result in reduced range?

Darryl Ramm

July 6th 12, 03:21 PM

On Friday, July 6, 2012 2:43:49 AM UTC-7, (unknown) wrote:
> The human eye focuses at "infinity" from a around three meters on out. I don't think I can get a PowerFlarm antenna that far away from me unless I'm looking at it from the back of a tandem two seater. I mounted a mock up of the portable and its antennas on the glare shield of my ASW-15 and found it very distracting and obstructive (my compass is in the panel and my yaw string is only an inch and a half long and is mounted far forward on the canopy so only the string itself is visible when seated in the glider).
>
> A friend of mine has been trying to purchase a portable for over a month but the dealer told him he wasn't shipping them because he was waiting for a(nother) fix from the manufacturer before selling any. He hasn't been able to get any updates on the situation since the initial contact.
>
> I'm waiting until the brick is out and has gone through several revisions.. I don't like the idea of being a retail customer and performing the duties of a beta tester. Whenever I get the brick I'm going to have to either ditch my mechanical vario so I can install the 57mm display or get a new electric vario/computer which can show the Flarm data on its primary display because there's no room left on the panel.
>
> One question I have is if the range is seriously decreased by mounting the antenna at an angle, does banking the glider also result in reduced range?

Why do you want to focus on the antenna? You are not supposed to be staring at it. Not focusing on it will (with the help of stereo vision) help it disappear from your view as you scan.

All of the vertically polarized radio signals we use (Airband VHF, transponders, FLARM, ADS-B, etc.) are affected by orientation differences between the transmitting and receiving antennas. By having antennas mounted as vertical as possible to begin with the largest extremes of relative antenna mis-alignment vs aircraft bank are minimized.

Darryl

Craig R.

July 6th 12, 03:24 PM

>> I'm waiting until the brick is out and has gone through several revisions. I don't like the idea of being a retail customer and performing the duties of a beta tester. Whenever I get the brick I'm going to have to either ditch my mechanical vario so I can install the 57mm display or get a new electric vario/computer which can show the Flarm data on its primary display because there's no room left on the panel.

No need to wait for future revisions. The PowerFlarms are performing as advertised. I was mildly skeptical about the performance, but after flying with a brick unit for the past 2 weeks at a contest, it worked admirably. My only problem was a faulty Butterfly display (bad control switch). The unit worked, but the interface was toast. The display was replaced I was good to go.

>> One question I have is if the range is seriously decreased by mounting the antenna at an angle, does banking the glider also result in reduced range?

My PowerFlarm A antenna is mounted about 25 deg off of vertical on the top of my glare shield. I had no issues identifying ships out as far as 6 SM. When turning, a distant ship would infrequently drop out for a moment, but would reacquire very quickly as the turn progressed (carbon fiber cockpit blocks the signal). This was not a problem with closer in ships. I might revise my antenna installation with a more conventional mounting bracket than what I am currently using, but maybe not. It worked very well even though it wasn't set in the ideal position.

noel.wade

July 7th 12, 03:45 AM

I took an in-flight photo of my PowerFLARM antenna installation (way
up in the nose of my DG-300). If you think the antenna obstructs too
much of your vision for safety, compare it to the yaw string! Glider
wings are much wider than either item, BTW - and I think you have a
better chance of seeing relative motion of the wings than picking out
the shape of a fuselage or vertical fin.

http://www.flickr.com/photos/noel_wade/7518094912/

For the record, my antenna sticks up slightly above my compass, and is
on a plastic arm that puts it 7" ahead of the compass so it has a
roughly 320-degree clear field-of-view. I can see targets 6-8 miles
away occasionally, and 4-6 miles away without any trouble - even at my
6 o'clock when the target is only 200 feet behind me, 100 feet below
me, and chasing my ass (ask me how I know!). The only time I lose lock
on sailplanes is when they're at least 2 miles away and thermalling
above my altitude. The target comes and goes; and I suspect that has
as more to do with their antenna and fuselage/internals than my
antenna.

My ADS-B antenna is mounted on the inside of my turtle-deck, and picks
up transponders at least 6 miles out.

I will admit that it took a solid day of work to install my PowerFLARM
and run all the wires and get all the cables working. There was
grumbling and cursing involved (mostly because I was having to mount
it under the seatpan as my DG-300 has no space left in the instrument
pedestal). However once I started flying with it, all was
forgiven. I flew with it in the Standard Class Nationals and I am
100% convinced that it was well worth the effort. I am VERY HAPPY I
have it. Because of the terrain and conditions, several tasks
included MATs with reciprocal headings - and on at least 2 or 3
occasions FLARM alerted me to head-on traffic near my altitude, flying
near cloudbase where I would NOT have seen the traffic until the last
moment.

I hope future generations of the product have a better form-factor and
become easier to install (or at least some enterprising distributor/
reseller starts offering custom wiring harnesses)... But the current
version is fine as it stands and offers a lot of value - and safety -
for the money!

--Noel
P.S. (OK, I _do_ wish they'd hurry up and get the logger
functionality working... I almost didn't have a valid flight trace at
the Nats and could have used a backup logger that's IGC-legal!)

bumper[_4_]

July 7th 12, 08:34 AM

On Friday, July 6, 2012 7:45:45 PM UTC-7, noel.wade wrote:
compare it to the yaw string!

I happen to like your yaw string! (grin)

bumper

Andy[_1_]

July 7th 12, 02:27 PM

On Jul 5, 9:10*am, bumper > wrote:

> As to making the antenna out of very thin wire; from my Nave ET days, a thin antenna element has a more narrow bandwidth. Since flarm uses a frequency hopping protocol (I think from 885 to 915 Mhz), thin may not work very well.

lower freq 902.20000000 upper freq 927.80000000

Source - FCC application for PFP (no application, or other
certification data, published for PFB).

Chris Nicholas[_2_]

July 9th 12, 06:31 AM

We are all faced with fitting these things to legacy gliders of varying geometry and materials. The carbon fibre fuselage seems to pose most problems.

I hope glider designers in future make installation of transponders, Flarm and PowerFlarm etc. easier, without dead spots or vision impairment.

Chris N

FLARM

July 9th 12, 07:31 AM

We have published an Application note for the FLARM antenna installation:
http://powerflarm.us/manuals-software-updates-and-release-notes/

Deep link:
http://powerflarm.us/wp-content/uploads/2012/04/PowerFLARM_Application_Note_ANTENNAS.pdf

Still a bit raw, but we will update it with more pictures and examples.

[email protected]

July 9th 12, 02:24 PM

On Monday, July 9, 2012 2:31:48 AM UTC-4, FLARM wrote:
> We have published an Application note for the FLARM antenna installation:
> http://powerflarm.us/manuals-software-updates-and-release-notes/
>
> Deep link:
> http://powerflarm.us/wp-content/uploads/2012/04/PowerFLARM_Application_Note_ANTENNAS.pdf
>
> Still a bit raw, but we will update it with more pictures and examples.

Looking at page 6, there is a much less offensive 1/4 wave antenna shown that Flarm folks say works well.
Any of you expert guys have an idea where we get on of these?
Thanks
UH

John Godfrey (QT)[_2_]

July 9th 12, 02:26 PM

On Monday, July 9, 2012 2:31:48 AM UTC-4, FLARM wrote:
> We have published an Application note for the FLARM antenna installation:
> http://powerflarm.us/manuals-software-updates-and-release-notes/
>
> Deep link:
> http://powerflarm.us/wp-content/uploads/2012/04/PowerFLARM_Application_Note_ANTENNAS.pdf
>
> Still a bit raw, but we will update it with more pictures and examples.

Excellent,

How do I get one of the 1/4 wave whip antenna's shown on p6 of the Application Note? Who it the manufacturer and what is the part number?

QT

Wayne Paul

July 9th 12, 03:10 PM

There must be some company that builds a nice FLARM compatible 1/2 wave
length base fed antenna similar to the one in the following link.
http://www.spectrumaudio.com/shure-ua820-f.html?gclid=CJaE95fgjLECFSZntgodnQJgIQ

Wayne
W7ADK
http://www.soaridaho.com/

"John Godfrey (QT)" wrote in message
...

On Monday, July 9, 2012 2:31:48 AM UTC-4, FLARM wrote:
> We have published an Application note for the FLARM antenna installation:
> http://powerflarm.us/manuals-software-updates-and-release-notes/
>
> Deep link:
> http://powerflarm.us/wp-content/uploads/2012/04/PowerFLARM_Application_Note_ANTENNAS.pdf
>
> Still a bit raw, but we will update it with more pictures and examples.

Excellent,

How do I get one of the 1/4 wave whip antenna's shown on p6 of the
Application Note? Who it the manufacturer and what is the part number?

QT

FLARM

July 9th 12, 03:57 PM

On Monday, July 9, 2012 6:26:24 AM UTC-7, John Godfrey (QT) wrote:

> How do I get one of the 1/4 wave whip antenna's shown on p6 of the Application > Note? Who it the manufacturer and what is the part number?

Mobile Mark PSTG0-925SE
http://www.tessco.com/products/displayProductInfo.do?sku=384213&eventPage=1
It is a 'special order' item, but as of this morning they have some in stock.

Note that the length and picture on the Tessco site are incorrect.
Actual length is 2 7/8 inch. Datasheet is here:
http://powerflarm.us/wp-content/uploads/2012/07/PSTG0-925SE.pdf

Don't bug the manufacturer (Mobile Mark) about these; they have a minimum order quantity of 250pcs...

Disclaimer:
This is not a product that FLARM has tested, supplies or officially endorses.
It will require the installation of a suitable ground plane and coaxial cables to work properly. Please do not ask us for individual support on this type of installation.

That being said; if installed well, this can be very slick...

Richard[_9_]

July 10th 12, 05:54 AM

On Monday, July 9, 2012 6:24:10 AM UTC-7, (unknown) wrote:
> On Monday, July 9, 2012 2:31:48 AM UTC-4, FLARM wrote:
> > We have published an Application note for the FLARM antenna installation:
> > http://powerflarm.us/manuals-software-updates-and-release-notes/
> >
> > Deep link:
> > http://powerflarm.us/wp-content/uploads/2012/04/PowerFLARM_Application_Note_ANTENNAS.pdf
> >
> > Still a bit raw, but we will update it with more pictures and examples.
>
> Looking at page 6, there is a much less offensive 1/4 wave antenna shown that Flarm folks say works well.
> Any of you expert guys have an idea where we get on of these?
> Thanks
> UH

Craggy Aero will have something similar in about a week

Richard
www.craggyaero.com

Matt Herron Jr.

July 10th 12, 06:34 AM

On Monday, July 9, 2012 7:10:55 AM UTC-7, Wayne wrote:
> There must be some company that builds a nice FLARM compatible 1/2 wave
> length base fed antenna similar to the one in the following link.
> http://www.spectrumaudio.com/shure-ua820-f.html?gclid=CJaE95fgjLECFSZntgodnQJgIQ
>
> Wayne
> W7ADK
> http://www.soaridaho.com/
>
>
>
> "John Godfrey (QT)" wrote in message
> ...
>
> On Monday, July 9, 2012 2:31:48 AM UTC-4, FLARM wrote:
> > We have published an Application note for the FLARM antenna installation:
> > http://powerflarm.us/manuals-software-updates-and-release-notes/
> >
> > Deep link:
> > http://powerflarm.us/wp-content/uploads/2012/04/PowerFLARM_Application_Note_ANTENNAS.pdf
> >
> > Still a bit raw, but we will update it with more pictures and examples.
>
> Excellent,
>
> How do I get one of the 1/4 wave whip antenna's shown on p6 of the
> Application Note? Who it the manufacturer and what is the part number?
>
> QT

I won't be buying powerFlarm until the antenna installation is as unobtrusive as my Transponder. Di-pole sticking up above the glare shield doesn't cut it. Figure out another way. You have plenty of headroom to boost the power and use a less efficient 1/2 or 1/4 wave antenna. PowerFlarm needs to step up and fix this problem.

Mike C

July 10th 12, 07:33 AM

On Jul 9, 11:34*pm, "Matt Herron Jr." > wrote:
> On Monday, July 9, 2012 7:10:55 AM UTC-7, Wayne wrote:
> > There must be some company that builds a nice FLARM compatible 1/2 wave
> > length base fed antenna similar to the one in the following link.
> >http://www.spectrumaudio.com/shure-ua820-f.html?gclid=CJaE95fgjLECFSZ....
>
> > Wayne
> > W7ADK
> >http://www.soaridaho.com/
>
> > "John Godfrey (QT)" *wrote in message
> ...
>
> > On Monday, July 9, 2012 2:31:48 AM UTC-4, FLARM wrote:
> > > We have published an Application note for the FLARM antenna installation:
> > >http://powerflarm.us/manuals-software-updates-and-release-notes/
> > >
> > > Deep link:
> > >http://powerflarm.us/wp-content/uploads/2012/04/PowerFLARM_Applicatio...
> > >
> > > Still a bit raw, but we will update it with more pictures and examples.
>
> > Excellent,
>
> > How do I get one of the 1/4 wave whip antenna's shown on p6 of the
> > Application Note? Who it the manufacturer and what is the part number?
>
> > QT
>
> I won't be buying powerFlarm until the antenna installation is as unobtrusive as my Transponder. *Di-pole sticking up above the glare shield doesn't cut it. *Figure out another way. *You have plenty of headroom to boost the power and use a less efficient *1/2 or 1/4 wave antenna. *PowerFlarm needs to step up and fix this problem.

Yep

Steve Koerner

July 10th 12, 06:04 PM

I share the feeling that the antenna sucks. But the benefit of PF is vastly greater than the annoynace of the antenna.

Eventually a better antenna solution will emerge. The system now is working remarkably well. It would be wiser to think of the present antenna as temporary.

Chris Nicholas[_2_]

July 10th 12, 07:30 PM

As I have remarked before, the best is the enemy of the good.

To those who are waiting for the best solution, I hope you don’t have a
collision meanwhile. The odds are that you will not. But somebody will.

If you were involved, what do you say at the inquest, or to the lawyers for
the other family?

“I had read it works, but I was waiting for a perfect installation, not
one that is good enough to avoid collisions. Sorry about your loss, but
tough.”

How deep are your, or your estate’s, pockets?

Chris N.

Craig Funston[_2_]

July 10th 12, 08:19 PM

I'm curious about the requirement for the secondary PowerFlarm dipole
antenna to be oriented vertically. I flew with a rental box in the R8
contest and had great results. I did, however, mount the secondary dipole
horizontally at the forward edge of the glare shield. This was based on
conversations with radio & avionics folks that had looked at these
particular antennas with a spectrum analyzer and found no difference in
performance based on orientation. We also couldn't think of a scenario
where the signal would need to be polarized. Is there a PowerFlarm expert
out there that can shed some light on this.

Thanks,
Craig

On Wed, 04 Jul 2012 20:42:39 -0700, Dave Nadler > wrote:

> On Wednesday, July 4, 2012 12:16:38 PM UTC-7, (unknown) wrote:
>> Having a glare-shield mounted antenna is like sitting behind a support
>> column at a basketball game.
>
> Complete Nonsense. The antenna and any decent
> mount are thin, and you won't notice them after
> 5 minutes. The angle blocked is only slightly
> more than your yaw string.
>
> Are you going to remove your yaw string too ?
>
> Really now.

--
Using Opera's revolutionary email client: http://www.opera.com/mail/

Andy[_1_]

July 10th 12, 09:05 PM

On Jul 9, 10:34*pm, "Matt Herron Jr." > wrote:
> I won't be buying powerFlarm until the antenna installation is as unobtrusive as my Transponder. *Di-pole sticking up above the glare shield doesn't cut it. *Figure out another way. *You have plenty of headroom to boost the power and use a less efficient *1/2 or 1/4 wave antenna. *PowerFlarm needs to step up and fix this problem.-

Certainly agree with the statement about power. FLARM recognized at
the start of development of the US FLARM that a higher power would be
required than for the rest of the world. This I assume was based on
the fact that the ISM band, which also happens to be the 33cm amateur
band, has multiple users, some using much higher power transmitters.
I have not seen any statement from FLARM indicating why a higher power
transmitter was not used when we had been told it would be required.

The limited field testing of PF has provided reports that the system
works as intended. How much, if any, of that flight testing has been
done in the vicinity a large metropolitan areas where interference
from other band users will likely be much greater than out in the
boonies of Utah?

Andy

FLARM

July 11th 12, 02:32 PM

On Tuesday, July 10, 2012 7:34:00 AM UTC+2, Matt Herron Jr. wrote:
> I won't be buying powerFlarm until the antenna installation
> is as unobtrusive as my Transponder.
Can you elaborate on your transponder antenna installation? We are pretty sure the PowerFLARM antenna has less requirements than your transponder...

> Di-pole sticking up above the glare shield doesn't cut it.

Relax guys.
The location above the glare shield is not required in most gliders for the core collision avoidance functionality, which needs a range of only about one nautical mile.

The reason the antenna type/placement has become a big discussion is that:
1) Initial PowerFLARM hardware had interference issues in some US location, we have since added a bandpass filter and will be upgrading existing units for free.

2) Our initial installation instructions were quite poor and some user installations violated basic antenna placement rules. This resulted in poor range, also for the well installed receiving aircraft.

3) Some pilots want the maximum possible range for tactical or entertainment purposes. That maximum is only achievable in the best location which often happens to be above the glare shield.

noel.wade

July 11th 12, 10:02 PM

On Jul 9, 10:34*pm, "Matt Herron Jr." > wrote:
> I won't be buying powerFlarm until the antenna installation is as unobtrusive as my Transponder.

Please see the latest response from the FLARM folks. BUT, please
remember that:

1) The PowerFLARM runs at a *much* lower power level than
Transponders. That means that antenna placement and visibility is
always going to be a slightly touchier issue than with transponders.

2) The Dipole is only 3 inches long (tip to tip) and very
unobtrusive.
I again refer you to the in-flight photo of my installation:
http://www.flickr.com/photos/noel_wade/7518094912/
And again, here's Tim Taylor's installation:
https://plus.google.com/photos/108936014984094330632/albums/5761722249435143009/5761722263754238914

So...
Is the FLARM antenna situation annoying? Yes.
Are there a few details about the PowerFLARM that I wish were
different? Yes.
Is it OK to grumble about this stuff? Sure.
Are people blowing the issues up larger than they need to be (on both
sides)? Yes.
Is the antenna situation a good reason to avoid buying it? Hell No!

I challenge anyone to find a PowerFLARM user who has installed the
system (after the initial range issues were sorted), and doesn't want
it or doesn't like using it.

--Noel

Eric Greenwell[_4_]

July 12th 12, 05:12 AM

On 7/5/2012 5:35 AM, John Godfrey (QT) wrote:

>> Thanks,
>> Best Regards, Dave "YO electric"
>>
>> PS: If you're interested in a mount for a flat-top
>> glare-shield (SH, etc) - send Rex a note.
>
> End fed dipole could also be very thin.

"Fat" antennas are used to broaden the frequency range of the antenna,
but I don't know if that is the reason for the PowerFlarm antenna width.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz

Eric Greenwell[_4_]

July 12th 12, 05:40 AM

On 7/8/2012 10:31 PM, Chris Nicholas wrote:
> We are all faced with fitting these things to legacy gliders of
> varying geometry and materials. The carbon fibre fuselage seems to
> pose most problems.
>
> I hope glider designers in future make installation of transponders,
> Flarm and PowerFlarm etc. easier, without dead spots or vision
> impairment.

You can already order your new glider with a transponder antenna, and
I'm sure you'll be able to order it with PowerFlarm antennas, once
PowerFlarm settles on a design (some time next year?).

I like the idea of mounting the brick in the top of the tail, where a
lot of gliders have a place for battery. My glider already has a two
wire cable there with 12 volts on it. I'd still have to run a cable
forward to the display.

The antennas could mounted inside the box in some cases; otherwise, the
two antennas could be mounted on a short extension of the TE probe
mount. The TE mount location should give the antennas an awesome view of
the world, even on a carbon glider; mounting in the box could also work
well on gliders with non-carbon horizontal stabilizers.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz

Eric Greenwell[_4_]

July 12th 12, 06:19 AM

On 7/10/2012 10:04 AM, Steve Koerner wrote:
> I share the feeling that the antenna sucks. But the benefit of PF is
> vastly greater than the annoynace of the antenna.
>
> Eventually a better antenna solution will emerge. The system now is
> working remarkably well. It would be wiser to think of the present
> antenna as temporary.

Yep. I have portable PF with two antennas sticking up. I didn't like
that the first few flights, but after seeing how much less tense it was
when thermalling with other PF equipped glider - I got over it.

Next season I'll install the perfect setup.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

Ramy

July 13th 12, 08:11 AM

On Wednesday, July 11, 2012 2:02:33 PM UTC-7, noel.wade wrote:
> On Jul 9, 10:34*pm, "Matt Herron Jr." > wrote:
> > I won't be buying powerFlarm until the antenna installation is as unobtrusive as my Transponder.
>
> Please see the latest response from the FLARM folks. BUT, please
> remember that:
>
> 1) The PowerFLARM runs at a *much* lower power level than
> Transponders. That means that antenna placement and visibility is
> always going to be a slightly touchier issue than with transponders.
>
> 2) The Dipole is only 3 inches long (tip to tip) and very
> unobtrusive.
> I again refer you to the in-flight photo of my installation:
> http://www.flickr.com/photos/noel_wade/7518094912/
> And again, here's Tim Taylor's installation:
> https://plus.google.com/photos/108936014984094330632/albums/5761722249435143009/5761722263754238914
>
> So...
> Is the FLARM antenna situation annoying? Yes.
> Are there a few details about the PowerFLARM that I wish were
> different? Yes.
> Is it OK to grumble about this stuff? Sure.
> Are people blowing the issues up larger than they need to be (on both
> sides)? Yes.
> Is the antenna situation a good reason to avoid buying it? Hell No!
>
> I challenge anyone to find a PowerFLARM user who has installed the
> system (after the initial range issues were sorted), and doesn't want
> it or doesn't like using it.
>
> --Noel

Noel, both your's and Tim's instalation looks great from an obvious reason: the antenna is installed behind the compass! But many of us don't have compass on top of the glare shield, which makes a big difference.

However I suspected that the claim that the whole dipole antenna must be above the glare shield is exaggerated, and this seem to be confirmed by the Flarm folks. I would like Flarm to clarify if in their opinion it is sufficient for collision avoidance to have the whole antenna below the glare shield.

Ramy

noel.wade

July 13th 12, 04:19 PM

On Jul 13, 12:11*am, Ramy > wrote:
> On Wednesday, July 11, 2012 2:02:33 PM UTC-7, noel.wade wrote:
> > On Jul 9, 10:34*pm, "Matt Herron Jr." > wrote:
> > > I won't be buying powerFlarm until the antenna installation is as unobtrusive as my Transponder.
>
> > Please see the latest response from the FLARM folks. *BUT, please
> > remember that:
>
> > 1) The PowerFLARM runs at a *much* lower power level than
> > Transponders. *That means that antenna placement and visibility is
> > always going to be a slightly touchier issue than with transponders.
>
> > 2) The Dipole is only 3 inches long (tip to tip) and very
> > unobtrusive.
> > I again refer you to the in-flight photo of my installation:
> >http://www.flickr.com/photos/noel_wade/7518094912/
> > And again, here's Tim Taylor's installation:
> >https://plus.google.com/photos/108936014984094330632/albums/576172224...
>
> > So...
> > Is the FLARM antenna situation annoying? Yes.
> > Are there a few details about the PowerFLARM that I wish were
> > different? Yes.
> > Is it OK to grumble about this stuff? Sure.
> > Are people blowing the issues up larger than they need to be (on both
> > sides)? Yes.
> > Is the antenna situation a good reason to avoid buying it? Hell No!
>
> > I challenge anyone to find a PowerFLARM user who has installed the
> > system (after the initial range issues were sorted), and doesn't want
> > it or doesn't like using it.
>
> > --Noel
>
> Noel, both your's and Tim's instalation looks great from an obvious reason: the antenna is installed behind the compass! But many of us don't have compass on top of the glare shield, which makes a big difference.

Sure, but even WITH the dipole and no compass, doesn't that mean that
you people still have *MORE* visibility than I do, with my "big old
compass" sitting in front of me?

Bottom line: The dipole ain't pretty, but it doesn't cover up enough
of your forward view to be of any concern. If you can stand having a
non-transparent yaw string, you can stand the dipole.

--Noel
P.S. I know of at least 1 LS-8 with PowerFLARM where only the top
half of the dipole sticks up through a hole in their glareshield. I
see them from about 4-5 miles out (instead of 6-8 miles for the best-
case installations), and they sometimes appear and disappear when
thermalling as the rearward transmissions are mostly blocked. But
overall the installation seems more than adequate.

kirk.stant

July 13th 12, 04:19 PM

I can't believe people are still whining about the aesthetics of a PF antenna on their glareshield!

No-one seems to mind a big stonkin useless whiskey compass up there, which is probably never looked at but blocks a lot more than a thin antenna! Or a big square of solid tape holding on their bright, long yaw string (Insert plug for Bumper's Mk IV, or clear tape, even...)

And again - at the distance the antenna is located, it has virtually no effect on your field of vision - if you are focused at infinity. If not, then you can put your iPad up there and it won't make any difference.

And Ramy, the Flarm folks have stated over and over that the Flarm antenna needs to be ABOVE the glareshield with the biggest field of view to work. The transponder antenna can be buried due to the much stronger signal it works with.

Just get the darn thing and stick it up with some sort of temporary mount until someone caters to your need for a pretty cockpit and comes up with a better antenna solution - trust me it's already in progress.

And yes, when a slicker looking antenna is available, I'll probably get one too - got to look sharp for all those glider groupies!

Kirk
66

bumper[_4_]

July 13th 12, 05:12 PM

On Friday, July 13, 2012 8:19:58 AM UTC-7, kirk.stant wrote:
(Insert plug for Bumper's Mk IV, or clear tape, even...)
> Kirk
> 66

Thanks for the plug, Kirk (g). WARNING thread hijack alert . . .

A word of caution, if you don't install a MKIV, then use wing tape or whatever, but do yourself a favor and avoid using clear tape to attach a yaw string!

Clear tape can be the absolute nastiest stuff to remove after it UV degrades. The adhesive turns solid and the clear plastic layer loses all mechanical strength so can't be pulled off. What remains has no further purpose in life but to "protect" the underlying hardened adhesive from any solvent one might be brave enough to try (and many solvents will damage Plexi, some instantly). I've worked an hour to remove clear tape and then had to polish the abused plexi before installing a MkIV.

Ramy

July 13th 12, 05:58 PM

Kirk, I actually do mind a compass in front and this was the first thing I did when purchase my glider was removed the compass from the top of the glare shield and installed a mark 4 yaw string. I agree that those who have a compass in front and white tape holding their yaw strings should not complain. As for how much the antenna needs to be above the glare shield the Flarm post above suggests it is less critical as some other posters suggested.
The Schleichers have already limited forward visibility to start with. Less of a problem in DG.

Ramy

kirk.stant

July 13th 12, 08:06 PM

On Friday, July 13, 2012 11:12:14 AM UTC-5, bumper wrote:
>
> Thanks for the plug, Kirk (g). WARNING thread hijack alert . . .
>
> A word of caution, if you don't install a MKIV, then use wing tape or whatever, but do yourself a favor and avoid using clear tape to attach a yaw string!
>
> Clear tape can be the absolute nastiest stuff to remove after it UV degrades. The adhesive turns solid and the clear plastic layer loses all mechanical strength so can't be pulled off. What remains has no further purpose in life but to "protect" the underlying hardened adhesive from any solvent one might be brave enough to try (and many solvents will damage Plexi, some instantly). I've worked an hour to remove clear tape and then had to polish the abused plexi before installing a MkIV.

Bumper, I've had good luck using Scotch SuperStrength Packaging tape - comes on a red dispenser. My primary use of this tape is to cover the big LS tail attachement hole on the top of the horizontal tail - been using it for 13 years with no problems yet. It also works fine for attaching a yawstring - a bit tricky to get the correct shape because the tape is not stretchy and has to be carefully cut but the result is almost as good as your hi-tech Mk IV. I've never had any problem getting the old tape or glue off when replacing the string.

Handy for doing a fleet of club gliders after heathens have stuck on yawstrings with duct tape!

Caveat - only used on gliders that are not tied down outside very long. So this tape may not work well if left outside all the time.

Cheers,

Kirk
66

Richard[_9_]

July 14th 12, 02:43 PM

On Friday, July 13, 2012 12:11:03 AM UTC-7, Ramy wrote:
> On Wednesday, July 11, 2012 2:02:33 PM UTC-7, noel.wade wrote:
> > On Jul 9, 10:34*pm, &quot;Matt Herron Jr.&quot; &gt; wrote:
> > &gt; I won&#39;t be buying powerFlarm until the antenna installation is as unobtrusive as my Transponder.
> >
> > Please see the latest response from the FLARM folks. BUT, please
> > remember that:
> >
> > 1) The PowerFLARM runs at a *much* lower power level than
> > Transponders. That means that antenna placement and visibility is
> > always going to be a slightly touchier issue than with transponders.
> >
> > 2) The Dipole is only 3 inches long (tip to tip) and very
> > unobtrusive.
> > I again refer you to the in-flight photo of my installation:
> > http://www.flickr.com/photos/noel_wade/7518094912/
> > And again, here&#39;s Tim Taylor&#39;s installation:
> > https://plus.google.com/photos/108936014984094330632/albums/5761722249435143009/5761722263754238914
> >
> > So...
> > Is the FLARM antenna situation annoying? Yes.
> > Are there a few details about the PowerFLARM that I wish were
> > different? Yes.
> > Is it OK to grumble about this stuff? Sure.
> > Are people blowing the issues up larger than they need to be (on both
> > sides)? Yes.
> > Is the antenna situation a good reason to avoid buying it? Hell No!
> >
> > I challenge anyone to find a PowerFLARM user who has installed the
> > system (after the initial range issues were sorted), and doesn&#39;t want
> > it or doesn&#39;t like using it.
> >
> > --Noel
>
> Noel, both your's and Tim's instalation looks great from an obvious reason: the antenna is installed behind the compass! But many of us don't have compass on top of the glare shield, which makes a big difference..
>
> However I suspected that the claim that the whole dipole antenna must be above the glare shield is exaggerated, and this seem to be confirmed by the Flarm folks. I would like Flarm to clarify if in their opinion it is sufficient for collision avoidance to have the whole antenna below the glare shield.
>
> Ramy

Ramy,

The antenna you may have been waiting for:

http://www.craggyaero.com/cables_&_antennas.htm

Approx 3" with a 6" ground plane bulkhead mount. I will install in my Ventus b and test today and tomorrow. I plan to put the ground on the underside of the panel cover.

Richard
www.craggyaero.com

Peter Higgs

July 14th 12, 03:19 PM

At 13:43 14 July 2012, Richard wrote:
>On Friday, July 13, 2012 12:11:03 AM UTC-7, Ramy wrote:
>> On Wednesday, July 11, 2012 2:02:33 PM UTC-7, noel.wade wrote:
>> > On Jul 9, 10:34=A0pm, "Matt Herron Jr." <m.=
> wrote:
>> > > I won't be buying powerFlarm until the antenna inst=
>allation is as unobtrusive as my Transponder.
>> >=20
>> > Please see the latest response from the FLARM folks. BUT, please
>> > remember that:
>> >=20
>> > 1) The PowerFLARM runs at a *much* lower power level than
>> > Transponders. That means that antenna placement and visibility is
>> > always going to be a slightly touchier issue than with transponders.
>> >=20
>> > 2) The Dipole is only 3 inches long (tip to tip) and very
>> > unobtrusive.
>> > I again refer you to the in-flight photo of my installation:
>> > http://www.flickr.com/photos/noel_wade/7518094912/
>> > And again, here's Tim Taylor's installation:
>> > https://plus.google.com/photos/108936014984094330632/albums/57617222=
>49435143009/5761722263754238914
>> >=20
>> > So...
>> > Is the FLARM antenna situation annoying? Yes.
>> > Are there a few details about the PowerFLARM that I wish were
>> > different? Yes.
>> > Is it OK to grumble about this stuff? Sure.
>> > Are people blowing the issues up larger than they need to be (on bot=
>h
>> > sides)? Yes.
>> > Is the antenna situation a good reason to avoid buying it? Hell No!
>> >=20
>> > I challenge anyone to find a PowerFLARM user who has installed the
>> > system (after the initial range issues were sorted), and doesn&#=
>39;t want
>> > it or doesn't like using it.
>> >=20
>> > --Noel
>>=20
>> Noel, both your's and Tim's instalation looks great from an
>obvio=
>us reason: the antenna is installed behind the compass! But many of us
>don&=
>#39;t have compass on top of the glare shield, which makes a big
>difference=
>..
>>=20
>> However I suspected that the claim that the whole dipole antenna must
be
>=
>above the glare shield is exaggerated, and this seem to be confirmed by
>the=
> Flarm folks. I would like Flarm to clarify if in their opinion it is
>suffi=
>cient for collision avoidance to have the whole antenna below the glare
>shi=
>eld.
>>=20
>> Ramy
>
>Ramy,
>
>The antenna you may have been waiting for:
>
>http://www.craggyaero.com/cables_&_antennas.htm
>
>Approx 3" with a 6" ground plane bulkhead mount. I will install in my
>Vent=
>us b and test today and tomorrow. I plan to put the ground on the
>undersid=
>e of the panel cover.
>
>Richard
>www.craggyaero.com

Hi Richard, unfortunately because of the brewster angle, the groundplane
type of antenna will not receive much from directly ahead, at the same
altitude, and even less beneath the groundplane.
The Dipole has a maximum response directly forward, but with a null
above... something like a ring doughnut.

Pete

Richard[_9_]

July 14th 12, 04:03 PM

On Saturday, July 14, 2012 7:19:34 AM UTC-7, Peter Higgs wrote:
> At 13:43 14 July 2012, Richard wrote:
> >On Friday, July 13, 2012 12:11:03 AM UTC-7, Ramy wrote:
> >> On Wednesday, July 11, 2012 2:02:33 PM UTC-7, noel.wade wrote:
> >> > On Jul 9, 10:34=A0pm, &quot;Matt Herron Jr.&quot; <m.=
> > wrote:
> >> > > I won&#39;t be buying powerFlarm until the antenna inst=
> >allation is as unobtrusive as my Transponder.
> >> >=20
> >> > Please see the latest response from the FLARM folks. BUT, please
> >> > remember that:
> >> >=20
> >> > 1) The PowerFLARM runs at a *much* lower power level than
> >> > Transponders. That means that antenna placement and visibility is
> >> > always going to be a slightly touchier issue than with transponders.
> >> >=20
> >> > 2) The Dipole is only 3 inches long (tip to tip) and very
> >> > unobtrusive.
> >> > I again refer you to the in-flight photo of my installation:
> >> > http://www.flickr.com/photos/noel_wade/7518094912/
> >> > And again, here&#39;s Tim Taylor&#39;s installation:
> >> > https://plus.google.com/photos/108936014984094330632/albums/57617222=
> >49435143009/5761722263754238914
> >> >=20
> >> > So...
> >> > Is the FLARM antenna situation annoying? Yes.
> >> > Are there a few details about the PowerFLARM that I wish were
> >> > different? Yes.
> >> > Is it OK to grumble about this stuff? Sure.
> >> > Are people blowing the issues up larger than they need to be (on bot=
> >h
> >> > sides)? Yes.
> >> > Is the antenna situation a good reason to avoid buying it? Hell No!
> >> >=20
> >> > I challenge anyone to find a PowerFLARM user who has installed the
> >> > system (after the initial range issues were sorted), and doesn&#=
> >39;t want
> >> > it or doesn&#39;t like using it.
> >> >=20
> >> > --Noel
> >>=20
> >> Noel, both your's and Tim's instalation looks great from an
> >obvio=
> >us reason: the antenna is installed behind the compass! But many of us
> >don&=
> >#39;t have compass on top of the glare shield, which makes a big
> >difference=
> >..
> >>=20
> >> However I suspected that the claim that the whole dipole antenna must
> be
> >=
> >above the glare shield is exaggerated, and this seem to be confirmed by
> >the=
> > Flarm folks. I would like Flarm to clarify if in their opinion it is
> >suffi=
> >cient for collision avoidance to have the whole antenna below the glare
> >shi=
> >eld.
> >>=20
> >> Ramy
> >
> >Ramy,
> >
> >The antenna you may have been waiting for:
> >
> >http://www.craggyaero.com/cables_&_antennas.htm
> >
> >Approx 3" with a 6" ground plane bulkhead mount. I will install in my
> >Vent=
> >us b and test today and tomorrow. I plan to put the ground on the
> >undersid=
> >e of the panel cover.
> >
> >Richard
> >www.craggyaero.com
>
> Hi Richard, unfortunately because of the brewster angle, the groundplane
> type of antenna will not receive much from directly ahead, at the same
> altitude, and even less beneath the groundplane.
> The Dipole has a maximum response directly forward, but with a null
> above... something like a ring doughnut.
>
> Pete

Pete,

I understand all this. I have tested with a spectrum analyzer and did not see a significant difference. Also PowerFlarm has recommend this antenna although they said a dipole may be slightly better. If you dipole is above the instrument panel I would suspect it is greately degraded by all the instruments carbon fiber etc underneath.
I will do some flight testing today and will post the results.

Richard
www.craggyaero.com

Peter Higgs

July 14th 12, 04:57 PM

At 15:03 14 July 2012, Richard wrote:
>On Saturday, July 14, 2012 7:19:34 AM UTC-7, Peter Higgs wrote:
>> At 13:43 14 July 2012, Richard wrote:
>> >On Friday, July 13, 2012 12:11:03 AM UTC-7, Ramy wrote:
>> >> On Wednesday, July 11, 2012 2:02:33 PM UTC-7, noel.wade wrote:
>> >> > On Jul 9, 10:34=3DA0pm, "Matt Herron Jr."=
> <m.=3D
>> > wrote:
>> >> > > I won't be buying powerFlarm until the antenna=
> inst=3D
>> >allation is as unobtrusive as my Transponder.
>> >> >=3D20
>> >> > Please see the latest response from the FLARM folks. BUT, =
>please
>> >> > remember that:
>> >> >=3D20
>> >> > 1) The PowerFLARM runs at a *much* lower power level than
>> >> > Transponders. That means that antenna placement and visibi=
>lity is
>> >> > always going to be a slightly touchier issue than with tran=
>sponders.
>> >> >=3D20
>> >> > 2) The Dipole is only 3 inches long (tip to tip) and very
>> >> > unobtrusive.
>> >> > I again refer you to the in-flight photo of my installation=
>:
>> >> > http://www.flickr.com/photos/noel_wade/7518094912/
>> >> > And again, here's Tim Taylor's installation=
>:
>> >> > https://plus.google.com/photos/108936014984094330632/albums=
>/57617222=3D
>> >49435143009/5761722263754238914
>> >> >=3D20
>> >> > So...
>> >> > Is the FLARM antenna situation annoying? Yes.
>> >> > Are there a few details about the PowerFLARM that I wish we=
>re
>> >> > different? Yes.
>> >> > Is it OK to grumble about this stuff? Sure.
>> >> > Are people blowing the issues up larger than they need to b=
>e (on bot=3D
>> >h
>> >> > sides)? Yes.
>> >> > Is the antenna situation a good reason to avoid buying it? =
>Hell No!
>> >> >=3D20
>> >> > I challenge anyone to find a PowerFLARM user who has instal=
>led the
>> >> > system (after the initial range issues were sorted), and do=
>esn&#=3D
>> >39;t want
>> >> > it or doesn't like using it.
>> >> >=3D20
>> >> > --Noel
>> >>=3D20
>> >> Noel, both your's and Tim's instalation looks great from=
> an
>> >obvio=3D
>> >us reason: the antenna is installed behind the compass! But many of u=
>s
>> >don&=3D
>> >#39;t have compass on top of the glare shield, which makes a big
>> >difference=3D
>> >..
>> >>=3D20
>> >> However I suspected that the claim that the whole dipole antenna=
> must
>> be
>> >=3D
>> >above the glare shield is exaggerated, and this seem to be confirmed =
>by
>> >the=3D
>> > Flarm folks. I would like Flarm to clarify if in their opinion it is
>> >suffi=3D
>> >cient for collision avoidance to have the whole antenna below the gla=
>re
>> >shi=3D
>> >eld.
>> >>=3D20
>> >> Ramy
>> >
>> >Ramy,
>> >
>> >The antenna you may have been waiting for:
>> >
>> >http://www.craggyaero.com/cables_&_antennas.htm
>> >
>> >Approx 3" with a 6" ground plane bulkhead mount. I will in=
>stall in my
>> >Vent=3D
>> >us b and test today and tomorrow. I plan to put the ground on the
>> >undersid=3D
>> >e of the panel cover.
>> >
>> >Richard
>> >www.craggyaero.com
>>=20
>> Hi Richard, unfortunately because of the brewster angle, the
groundplane
>> type of antenna will not receive much from directly ahead, at the same
>> altitude, and even less beneath the groundplane.
>> The Dipole has a maximum response directly forward, but with a null
>> above... something like a ring doughnut.
>>=20
>> Pete
>
>Pete,
>
>I understand all this. I have tested with a spectrum analyzer and did
>not=
> see a significant difference. Also PowerFlarm has recommend this
antenna
>=
>although they said a dipole may be slightly better. If you dipole is
>above=
> the instrument panel I would suspect it is greately degraded by all the
>in=
>struments carbon fiber etc underneath.
>I will do some flight testing today and will post the results.
>
>Richard
>www.craggyaero.com
>
Hi Richard, there are several types of groundplane antennas, including the
one with three counterpoises at 45 deg to the horizontal. All tested by
ground stations, so not really in 'free space'. Also one with the
grondplane in the form of a sharp cone.
However there is one variation, called the 'Sleeved Balun' which uses a
sleeve of second co-ax outer, doubled back along the co-ax. It has to be
at least a quarter wave (taking into account the dielectric constant.) but
I should think 3 inches would be sufficient.
Whatever you use there is bound to be a Null somewhere, and overhead and
underneath with the dipole is probably best in this application.
A proper match of the grondplane (or counterpoise.) is mostly needed to
reduce any SWR on the co-ax, which would otherwise become a radiating part
of the system.

Pete

Richard[_9_]

July 15th 12, 04:58 AM

On Saturday, July 14, 2012 8:57:07 AM UTC-7, Peter Higgs wrote:
> At 15:03 14 July 2012, Richard wrote:
> >On Saturday, July 14, 2012 7:19:34 AM UTC-7, Peter Higgs wrote:
> >> At 13:43 14 July 2012, Richard wrote:
> >> >On Friday, July 13, 2012 12:11:03 AM UTC-7, Ramy wrote:
> >> >> On Wednesday, July 11, 2012 2:02:33 PM UTC-7, noel.wade wrote:
> >> >> > On Jul 9, 10:34=3DA0pm, &quot;Matt Herron Jr..&quot;=
> > <m.=3D
> >> > wrote:
> >> >> > > I won&#39;t be buying powerFlarm until the antenna=
> > inst=3D
> >> >allation is as unobtrusive as my Transponder.
> >> >> >=3D20
> >> >> > Please see the latest response from the FLARM folks. BUT, =
> >please
> >> >> > remember that:
> >> >> >=3D20
> >> >> > 1) The PowerFLARM runs at a *much* lower power level than
> >> >> > Transponders. That means that antenna placement and visibi=
> >lity is
> >> >> > always going to be a slightly touchier issue than with tran=
> >sponders.
> >> >> >=3D20
> >> >> > 2) The Dipole is only 3 inches long (tip to tip) and very
> >> >> > unobtrusive.
> >> >> > I again refer you to the in-flight photo of my installation=
> >:
> >> >> > http://www.flickr.com/photos/noel_wade/7518094912/
> >> >> > And again, here&#39;s Tim Taylor&#39;s installation=
> >:
> >> >> > https://plus.google.com/photos/108936014984094330632/albums=
> >/57617222=3D
> >> >49435143009/5761722263754238914
> >> >> >=3D20
> >> >> > So...
> >> >> > Is the FLARM antenna situation annoying? Yes.
> >> >> > Are there a few details about the PowerFLARM that I wish we=
> >re
> >> >> > different? Yes.
> >> >> > Is it OK to grumble about this stuff? Sure.
> >> >> > Are people blowing the issues up larger than they need to b=
> >e (on bot=3D
> >> >h
> >> >> > sides)? Yes.
> >> >> > Is the antenna situation a good reason to avoid buying it? =
> >Hell No!
> >> >> >=3D20
> >> >> > I challenge anyone to find a PowerFLARM user who has instal=
> >led the
> >> >> > system (after the initial range issues were sorted), and do=
> >esn&#=3D
> >> >39;t want
> >> >> > it or doesn&#39;t like using it.
> >> >> >=3D20
> >> >> > --Noel
> >> >>=3D20
> >> >> Noel, both your's and Tim's instalation looks great from=
> > an
> >> >obvio=3D
> >> >us reason: the antenna is installed behind the compass! But many of u=
> >s
> >> >don&=3D
> >> >#39;t have compass on top of the glare shield, which makes a big
> >> >difference=3D
> >> >..
> >> >>=3D20
> >> >> However I suspected that the claim that the whole dipole antenna=
> > must
> >> be
> >> >=3D
> >> >above the glare shield is exaggerated, and this seem to be confirmed =
> >by
> >> >the=3D
> >> > Flarm folks. I would like Flarm to clarify if in their opinion it is
> >> >suffi=3D
> >> >cient for collision avoidance to have the whole antenna below the gla=
> >re
> >> >shi=3D
> >> >eld.
> >> >>=3D20
> >> >> Ramy
> >> >
> >> >Ramy,
> >> >
> >> >The antenna you may have been waiting for:
> >> >
> >> >http://www.craggyaero.com/cables_&_antennas.htm
> >> >
> >> >Approx 3" with a 6" ground plane bulkhead mount. I will in=
> >stall in my
> >> >Vent=3D
> >> >us b and test today and tomorrow. I plan to put the ground on the
> >> >undersid=3D
> >> >e of the panel cover.
> >> >
> >> >Richard
> >> >www.craggyaero.com
> >>=20
> >> Hi Richard, unfortunately because of the brewster angle, the
> groundplane
> >> type of antenna will not receive much from directly ahead, at the same
> >> altitude, and even less beneath the groundplane.
> >> The Dipole has a maximum response directly forward, but with a null
> >> above... something like a ring doughnut.
> >>=20
> >> Pete
> >
> >Pete,
> >
> >I understand all this. I have tested with a spectrum analyzer and did
> >not=
> > see a significant difference. Also PowerFlarm has recommend this
> antenna
> >=
> >although they said a dipole may be slightly better. If you dipole is
> >above=
> > the instrument panel I would suspect it is greately degraded by all the
> >in=
> >struments carbon fiber etc underneath.
> >I will do some flight testing today and will post the results.
> >
> >Richard
> >www.craggyaero.com
> >
> Hi Richard, there are several types of groundplane antennas, including the
> one with three counterpoises at 45 deg to the horizontal. All tested by
> ground stations, so not really in 'free space'. Also one with the
> grondplane in the form of a sharp cone.
> However there is one variation, called the 'Sleeved Balun' which uses a
> sleeve of second co-ax outer, doubled back along the co-ax. It has to be
> at least a quarter wave (taking into account the dielectric constant.) but
> I should think 3 inches would be sufficient.
> Whatever you use there is bound to be a Null somewhere, and overhead and
> underneath with the dipole is probably best in this application.
> A proper match of the grondplane (or counterpoise.) is mostly needed to
> reduce any SWR on the co-ax, which would otherwise become a radiating part
> of the system.
>
> Pete

Pete,

After flying with the Antenna with the 6" ground plane today, I can say it isn't significantly different than the dipole antenna. I still recommend that all use both antennas. I have the 6" ground plane one on my instrument panel cover and a dipole attached vertily to the vent in the nose of my ventus b.

The arch enenmy of perfect is just good enough.

Richard
www.craggyaero.com