ARCHER Antenna for COM not NAV

Anyone have any experience using an in-wing tip archer type antenna for COM and not NAV. I understand that COM waves are vertical while the NAV waves are horizontal--the model 1a on aircraft spruce is supposedly adapted for COM and shows the antenna mounted at a sloped angle from the bottom of the wing chord to the top of the wing tip. Is that sufficient for transmitting 25-50 miles?

My experience from 20 years ago. I made a wingtip Comm antenna, a builder friend bought the Archer Comm antenna. Mine worked, his did not (as in when flying in formation I had to relay ATC comms for him).

I built the antenna to take the maximum space in the wingtip for the vertical part of the arm coming off the rib. Then I tuned the antenna for resonance. It was ok, but I later used it only for Comm #2. On the next two RV builds I used a standard bent whips for both Comm antennas - but still today swear by my homebrew wingtip VOR antenna.

If you go down this road you will need to know what you are doing WRT how to get the most out of it.

Carl

I tried it with as much vertical as I could get - more like a 45 - and wasn't happy with it. I put a bent whip on to replace it.

Ed Holyoke

Due to the polarization of the signal, the Archer antenna design works quite well with Nav signals - not so much with Comm.

Mine never worked. I replaced it with a CI-122.

There was an ARCHER COMM antenna design that was marketed years ago. They were designed to be VERTICAL mounted in a fiberglass tip on top of the vertical stabilizer. Many T-18 guys had good luck with them. The late Jim Ayres had one in his RV-3 that appeared to work ok. It was in a larger fiberglass tip on the vertical stabilizer.

From HAM radio, there is approximately 18 dB loss between vertical and horizontal polarization. For every 3 dB increase, the power doubles or 3 dB decrease power halfs. That is why people have had poor to bad results placing a comm antenna in a wingtip.

RV6_flyer said:

From HAM radio, there is approximately 18 dB loss between vertical and horizontal polarization. For every 3 dB increase, the power doubles or 3 dB decrease power halfs. That is why people have had poor to bad results placing a comm antenna in a wingtip.

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Follow the guidance in post #2. You must tip the leading edge to get as much vertical throw as the wingtip allows. You must tune the parallel plate capacitor to get the antenna to accept as much of the signal as possible. You need to rely on the end rib being a very non-ideal ground plane (to get any signal propagating toward the fuselage). Done right, you’ll have a fair antenna. Not as good as an external whip, not as bad as those who don’t follow Carl’s advice would have you believe.