Mark,? One of the things from that CD on making your on antenna you let me use is that the transmission of that transponder antnna is in the microwave band. ?You should have some type of grounded barrier between the antenna and your important parts of you body. ?You don't have this issue with metal skin airplanes.
Paul Visk Belleville Il 618 406 4705 Sent on the new Sprint Network from my Samsung Galaxy S?4. <div>-------- Original message --------</div><div>From: Mark Langford via KRnet <krnet at list.krnet.org> </div><div>Date:10/14/2014 7:02 AM (GMT-06:00) </div><div>To: 'KRnet' <krnet at list.krnet.org> </div><div>Subject: Re: KR> transponder antenna </div><div> </div>Seeing the transponder fairing photo (second photo down at http://www.n56ml.com/fairings.html ) reminds me of the ultimate wisdom I finally attained on transponder antennas...there's no better fairing than putting the stupid antenna inside the fuselage! My main obstacle to that revelation during N56ML construction was that the ground plane needed to be above the antenna, but I later realized that a ~5" circle made from an aluminum "foil" pie pan would work fine. I glued a little tab of leftover 3/32" thick plywood to the top of one of the upper fuselage cross braces, drilled a hole for the little transponder rod antenna, capped it off with the "ground plane" and it was a lightweight zero drag installation! Another reason I did this was because I was told by a very sharp EE/avionics guy that oil and crud accumulating on the outside of my fairing (when it was mounted outside) would change the impedance of the antenna, reducing its efficiency and even presenting a chance of damaging the transponder due to mismatch. The reason I am sensitive to this is because we were discussing why my transponder had suddenly croaked. Another potential reason is that the BNC connector may have come loose...and it was just sitting on top of the antenna without the twist-lock engaged. Don't operate a transponder without an antenna connected to it, he said, especially the IDENT button! Mark Langford, Harvest, AL ML at N56ML.com www.N56ML.com _______________________________________________ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
