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Dan Marotta
August 15th 19, 12:21 AM
I've been using the center fed dipoles on top of the glare shield of my
Stemme but I just installed a blade antenna on the bottom of the fuselage.

My plan is to feed the lower blade antenna with the Flarm A output and
the glare shield mounted dipole with the receive-only B input to the
PowerFlarm portable.Â* I'll make a few flights and then send logs to
Flarm for range analysis.Â* Then I'll swap the A and B inputs and
repeat.Â* Whichever shows the best performance will be the final
configuration.

Any comments or suggestions?
--
Dan, 5J

August 15th 19, 03:54 AM
I wonder if the range analysis checks your tx or rx or both.
You might need other folks' logs to check the tx.

If so, then a test might be to just use port A on one antenna at a time.

Dan Daly[_2_]
August 15th 19, 12:15 PM
On Wednesday, August 14, 2019 at 10:54:46 PM UTC-4, wrote:
> I wonder if the range analysis checks your tx or rx or both.
> You might need other folks' logs to check the tx.
>
> If so, then a test might be to just use port A on one antenna at a time.

An excellent tool for tx is https://ktrax.kisstech.ch/flarm-liverange/ . Insert your ICAO ID and you get a plot of db received vs range in km, and a plan chart. You do need to be in range of an OGN receiver. If you don't have a receive, here's an ICAO ID for one of our club gliders you can use (good for about a week): C059F6

Details on the Open Glider Network at http://wiki.glidernet.org/

Dan Daly[_2_]
August 15th 19, 12:20 PM
On Thursday, August 15, 2019 at 7:15:27 AM UTC-4, Dan Daly wrote:
> On Wednesday, August 14, 2019 at 10:54:46 PM UTC-4, wrote:
> > I wonder if the range analysis checks your tx or rx or both.
> > You might need other folks' logs to check the tx.
> >
> > If so, then a test might be to just use port A on one antenna at a time..
>
> An excellent tool for tx is https://ktrax.kisstech.ch/flarm-liverange/ . Insert your ICAO ID and you get a plot of db received vs range in km, and a plan chart. You do need to be in range of an OGN receiver. If you don't have a receive, here's an ICAO ID for one of our club gliders you can use (good for about a week): C059F6
>
> Details on the Open Glider Network at http://wiki.glidernet.org/

Here's a better one that got further away from the receivers: C053F2

Dan Marotta
August 15th 19, 05:10 PM
Good idea.Â* That and the OGN since we have one at Moriarty.Â* Take a look
at THIS
<https://ktrax.kisstech.ch/cgi-bin/flarm-txrange.cgi?command=plot&flarmid=ade5fe>
and can anyone say why my transmission is so crappy?Â* Maybe because the
antenna is on the field and I'm quickly above that?

Another question for the antenna gurus:Â* Why is the as delivered A
antenna longer than the B antenna?Â* Are they different frequencies? Why
not use the longer A antenna on the B port and the blade on the A port?

So many combinations to try...

On 8/14/2019 8:54 PM, wrote:
> I wonder if the range analysis checks your tx or rx or both.
> You might need other folks' logs to check the tx.
>
> If so, then a test might be to just use port A on one antenna at a time.

--
Dan, 5J

Dan Daly[_2_]
August 15th 19, 05:32 PM
On Thursday, August 15, 2019 at 12:10:11 PM UTC-4, Dan Marotta wrote:
> Good idea.Â* That and the OGN since we have one at Moriarty.Â* Take a
> look at THIS
> and can anyone say why my transmission is so crappy?Â* Maybe because
> the antenna is on the field and I'm quickly above that?

While there is a null above the OGN antenna, it is very small. More likely, the antenna transmissions are shielded by the carbon fiber fuselage of the Stemme so nothing goes down (I saw a recreation of two gliders who hit in an FAI contest; same path, both carbon fiber. Transmission of top guy doesn't go down, bottom guy's transmission block by top guy's fuselage - result, two parachutes). Take a line from the top of the antenna to the side of the carbon tub and that describes the first time the OGN will see you. The single hit close in is probably during a turn. Moving the antenna out to the side of the panel would help.
The number of hits is very small; you can see we get ~7400 hits during a flight, you're under 500.
If you use this, you can have someone click on your OGN target and it gives your received signal strength at the antenna in db, which is handy info:
http://glidertracker.org/#lat=1105585&lon=6428048&z=5
I see your cpu is running at 62C at 12 EDT today; that's pretty warm. you might want to put a fan on it. I use flight aware orange dongle as receiver, and find it doesn't like high temps a bunch.
Nice ranges on the 0E0 receiver, though; out to 130 km at 17000' ( http://ognrange.onglide.com/#0E0,max,recent,35.03796_-105.60993,8.53333333333334,#80000040:#008000ff,cir cles; ). Pretty good for a transmit signal of two hundredths of a watt!

George Haeh
August 15th 19, 05:44 PM
I'm getting good range numbers with long Flarm A & B antennae on opposite sides of the canopy on my ASW-27.

I upgraded to a Core 1.1 and am waiting for "Innovation", Science and Economic Development Canada to get off their keisters and approve transmit on both antennae.

Dan Daly[_2_]
August 15th 19, 06:05 PM
On Thursday, August 15, 2019 at 12:44:26 PM UTC-4, George Haeh wrote:
> I'm getting good range numbers with long Flarm A & B antennae on opposite sides of the canopy on my ASW-27.
>
> I upgraded to a Core 1.1 and am waiting for "Innovation", Science and Economic Development Canada to get off their keisters and approve transmit on both antennae.

Hi George - do you know that it's been submitted for such testing?
Dan

George Haeh
August 15th 19, 07:59 PM
Na, that's beyond my pay grade.

TSB is investigating the recent collision between a glider and C-182 towplane, possibly equipped with top and bottom external PowerFLARM antennae, only one of which would be transmitting.

I've had two close encounters with gliders underneath my carbon fiber fuselage when my PowerFLARM antenna was mounted on my glareshield.

Dan Daly[_2_]
August 15th 19, 08:38 PM
On Thursday, August 15, 2019 at 2:59:38 PM UTC-4, George Haeh wrote:
> Na, that's beyond my pay grade.
>
> TSB is investigating the recent collision between a glider and C-182 towplane, possibly equipped with top and bottom external PowerFLARM antennae, only one of which would be transmitting.
>
> I've had two close encounters with gliders underneath my carbon fiber fuselage when my PowerFLARM antenna was mounted on my glareshield.

Carbon fiber is a mixed blessing...

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