PowerFLARM antenna mounts

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/10893...22263754238914

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

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/10893...bums/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.

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

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.

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

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

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, "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/10893...22263754238914
>
> 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

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

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/10893...bums/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

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, "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/10893...bums/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

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

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/10893...330632/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