Antenna Location & GPS Input

[Moffrestorer]

Perhaps Randolph or LAS Aerospace could advise on the paint's electrical screening properties. AIUI the silver dope is applied for its UV protection of the fabric.

[Mig29fuk]

I've put ADS-B and GPS Antennae within the wing interior fixed by Velcro. It's standard pre-war wooden ribs and spar with Ceconite covering works fine.
My PAW Aerial is a PUC Type fixed above the Parasol Wing in centre and biased towards front of Aircraft.
All works well.
Gerry

[T67M]

I was relating the results from a test conducted as part of a building project I'm working on. Sadly I don't have direct access to the necessary test equipment to measure an aircraft, however I too would be surprised if doped fabric presented much attenuation even with the silver.

[Robski]

 
Seems I may have created a monster here!

I have the Starduster fuselage all covered, silvered and painted (lairy yellow - lovely) in my garage. Unfortunately getting it out is going to require removal of the undercarriage - not difficult, but not quick either - so testing the hypothesis in the open air is not really an option.

My PAW is now installed behind the dash of the RV, so extracting that is non-trivial too!

But...

I will dig out my old Garmin GPS III Pilot and use that for a bit of GPS testing, assuming I can actually get a GPS fix in the garage in the first place.

[exfirepro]

Thanks Rob,

It will be useful to hear your results.

Regards

Peter

[Robski]

I will dig out my old Garmin GPS III Pilot and use that for a bit of GPS testing, assuming I can actually get a GPS fix in the garage in the first place.

Well it appears to make little difference.

Looks like I have been wasting everyones time on this. 

[Paul_Sengupta]

Noooo, not wasting time...more like getting us all guessing the outcome! Should have had a poll... 

[exfirepro]

Thanks Rob,

Certainly NOT a waste of time - now we all know the answer for sure, but I have to say - definitely a relief!

We can continue to advise users with some sense of 'authority'. I must admit you did have me worried for a while.  

Regards

Peter

[Fisherman]

1. Can anyone tell me please, the optimum length to shorten the antenna and how to measure the length exactly?
2. Has anyone tried different antenna positions in an RV? and which positions are best?
Thanks

[exfirepro]

Hi,

I assume you are talking about the 'thinner' 1090MHz antenna? There is a long thread about this here... http://forum.pilotaware.com/index.php/topic,438.msg5661.html#msg5661

As signals on this frequency are from strong powerful sources (compared to PAW P3i), and this antenna is 'receive only', the final length is far from critical. The length advised is about 65mm, measured from the coax attachment point inside the antenna base. For practical purposes, prise the black cap off the top of the whip then cut the whip part in half and glue the top back on. This will be close enough. It's easiest to cut it with a good pair of side cutters, but watch your eyes when the cut bit flies off. DON'T be tempted to cut it too short as this could have a detrimental effect on the Mode C/S Alerts.

Unless you are going for external antennas, the coaming is always a good location, but some of our RV users may have other suggestions.

Regards

Peter

[Fisherman]

Thanks.  That's a great help.