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GPS antenna in wingtips

Might, depending on design. If the receiver's in the puck, then probably. There's even a product (Skybeacon) on the market now that combines GPS/ADS-B with a position light, and you know a strobe will be nearby. If the antenna must feed GigaHz frequencies to the receiver in the cabin, cable length matters a lot due to simple signal loss, even without the strobe question.

But in my plane, I'd ask, 'why?' Lots of mounting options in/on the cabin, under the cowl forward of the firewall, etc that are a lot easier (and lighter, in cable weight).

Charlie
 
The coax length would be the problem, I think. You're dealing with GPS signals that are way down in the thermal noise level and you need all the signal you can get. Just MHO.
 
Should work fine

I have two GPS antennas in the right wingtip of my RV-7 - a Dynon GPS-2020 "puck" connected to my Skyview via RS-232, and a Garmin GA-57X connected to my Garmin GDU-375 via RG-400 coax. Both are WAAS antennas. Both work just fine - never had any sort of signal loss on either one of them.

BTW - I have AeroLEDs NAV/Strobe lights in my wingtips, so I can't specifically speak to possible interference from traditional strobe tubes.
 
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Dan, I know everyone (probably including Dynon) calls those 'antennas', but they are actually receivers. The only thing traveling on the wire is power & digital data. Most 'pucks' these days are actually receivers, but if we aren't clear on what we're talking about, someone will read the thread & think they can remote the external antenna for their portable (396, 496, etc) out at the wingtip. Not likely to work well, in those cases.

edit: Just saw that the Garmin is coax, so it might actually be at least IF instead of digital data. the GDU375 is too new for me. :)

Charlie
 
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Dan, I know everyone (probably including Dynon) calls those 'antennas', but they are actually receivers. The only thing traveling on the wire is power & digital data. Most 'pucks' these days are actually receivers, but if we aren't clear on what we're talking about, someone will read the thread & think they can remote the external antenna for their portable (396, 496, etc) out at the wingtip. Not likely to work well, in those cases.

edit: Just saw that the Garmin is coax, so it might actually be at least IF instead of digital data. the GDU375 is too new for me. :)

Charlie

Point was I have one of each "type" and reception is great with both.

BTW, the GDU-375 is one of the older G3X displays. It can also be used as a standalone MFD, which is how I am using it.
 
I had two GPS antenna in my RV7A wingtip, one from 430W and one from GRT. Both worked flawlessly and even pickup signal in the hanger. I am planning on installing my 650 and G3X in the wingtip again.
Under the cowl has fair amount of heat and also I believe there is a minimum cable length that is required.
 
I have all three of my GPS antennas and XM radio antenna stuck to my glair shield with Velcro.

No interference issues, short cable runs, and easy maintenance!

One antenna was white and I covered it with the same loop Velcro fabric that I covered the glair shield with. No more reflection issues.
 
It's good to hear that newer GPS antennas can handle such long cable runs. But Bill and I seem to agree about simplicity of installation. :)

Charlie
 
My experience

I have a Garmin GPS 18 gps mounted in the left wing tip of our RV7a as gps2 into the GRT EFIS. It works flawlessly. There is no coax to run, just power and a serial line back to the GRT.. simple
 
Are there any particular requirements for GPS receiver/antenna distance from aircraft centerline that are relevant to an installation intended for use as an IFR navigator for enroute and approach guidance?
 
Requirements

Are there any particular requirements for GPS receiver/antenna distance from aircraft centerline that are relevant to an installation intended for use as an IFR navigator for enroute and approach guidance?

When I went through this with my Avidyne IFD440, I couldn't find anything that specifically required center line mounting - just the typical admonitions to make sure it had a clear view with no shadowing, etc. That said, I moved the Garmin GA-57X antenna for my GDU-375 out to the wingtip from its previous location on the top of the aft fuselage to make room for the GA-37 antenna used for the IFD440. For IFR work, I didn't want the approx 12.5 foot offset from center line I would have had with it in the wing. Probably wasn't really an issue but . . . . .
 
Are there any particular requirements for GPS receiver/antenna distance from aircraft centerline that are relevant to an installation intended for use as an IFR navigator for enroute and approach guidance?

Garmin provides GPS and comm antenna installation guidance in their installation manuals.
 
For IFR work, I didn't want the approx 12.5 foot offset from center line I would have had with it in the wing. Probably wasn't really an issue but . . . . .

I use an Archer antenna in the wingtip for ILS approaches. I just can't fly well enough to notice that I'm 12.5 feet off center due to the antenna.... -:)

However, for GPS I would follow the manufacturer's instructions. They're usually in the installation manual. Remember these signals are incredibly weak, and the TSO instructions promise you will get the best performance possible under the most trying conditions. Something that few of us are capable of easily testing on our own.
 
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