Do you use a ground plane for your radio?

[Steve Sands]

I am installing a Garmin GTR 200. The old radio had a ground plane about 2 inches by 3 inches tucked under the antennae. The Garmin says it needs a ground plane at least 18 x 18 with an antennae. What do you all use?

Thanks,
Steve Sands

[desertdave]

I very thin piece of aluminum is all you need.

[Steve Sands]

I very thin piece of aluminum is all you need.

Hi DesertDave, I would use very thin aluminum, yes, but do you have a ground plane and how big is it. Thank you.

[jiott]

I use a ground plane of 4 copper wires, about 18" long, in a cross pattern under my antenna. The wires are easy to zip tie to the structural tubing, and exact 90 degree quadrants are not required.

[efwd]

I use the airframe and the airframe only. Tony Bingelis of Experimental Aircraft fame suggested it (when talking about steel tube airframe) so I followed. I have not had anyone complain and I haven't any complaint either. I use that same radio. I suppose you would need to know what antenna I was using to get the truth as to whether you would get the same mileage. But, apparently a ground plane is unnecessary. Possibly I could get more range maybe but in this slow airplane I always reach my contacts within plenty of time before I reach their airspace.

[alexM]

18x18! Wow.

According to Garmin you'd have to locate your magnetometer about 50' from the aircraft for it to work properly. Yes joking, but they seem super conservative on their installation instructions.

[Steve Sands]

I use a ground plane of 4 copper wires, about 18" long, in a cross pattern under my antenna. The wires are easy to zip tie to the structural tubing, and exact 90 degree quadrants are not required.

Jim, thank you for the note. I like that idea as it seems a lot simpler than a rectangular sheet of thin Al. Hope to meet you at one of the Oregon fly-in's next year.

Steve Sands

[PapuaPilot]

I used aluminum discs for my plane and it has worked very well.

Here is another way using foil tape. There is a video on the EAA Hints for Homebuilders about this method at: https://www.eaa.org/Videos/Hints-for.../6264738687001

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[jiott]

Eddie, I went for about 5 years without a ground plane in my SS7, and like you had no problems with range. However, 3 years ago I flew to Oshkosh and traveled side by side with a friend in an all metal airplane. We were tuned to the same frequencies and he seemed to be able to pick up ATIS information quite a while before it came thru on my radio (Garmin SL40). That's when I began to realize that my radio was plenty functional, but quite limited in range in comparison to others. After I got home I installed the ground plane and immediately noticed a increase in range. Your mileage may vary, but that was my experience.

[efwd]

Jim, I have an annual coming in February and I was going to do exactly as you have done just to see. I suspect I will gain distance as you have experienced. Just not sure I will ever look to pick up ATIS that far out. Having said that, it is ATIS that I have tried to receive from afar without success. I have to go through Ontario Intl airport airspace before they hand me off to Chino tower. I have tried to get ATIS from both facilities before making my first call but have not been able. So, I just wait and try to monitor Chino while up with ONT tower. Doesn't always work out, hence the reason I was anticipating taking your advice and was going to give it a whirl. I'll let you know.