Testing your Experimental Aircraft's Communication Antenna

[@LTVoyager]

Minor correction here: minimum SWR does not imply the antenna is resonant. This would only be the case if the antenna radiation resistance matched the transmission cable resistance, which is seldom the case. Minimum SWR just means the minimum amount of the transmitted signal is being reflected back to the transmitter.

[@prof.heinous191]

Very useful! Requesting a story on minimum drag antennas...

[@flexairz]

An even more important antenna property not mentioned here is the bandwidth. This is the range of frequencies around the lowest resonant point where the SWR stays below 1 to 2.0. For a COM antenna between 118 and 136 MHz with a center freq of 127 MHz.

[@gvrose1]

Your an amazing guy with so much knowledge. I would like to see how to diagnose a broken antenna or a coax cable that is too long or short.. another video perhaps?

[@cessnapilot5905]

Thanks for the advice!!!. Did not know about this avionics equipment for testing. I just have my nav/radio repaired and came to find out that my antenna was cracked, which caused the damage in my nav/radio. Best regards.

[@muhammadsteinberg]

@Cessna Pilot.....RF doesn't know it's being used for avionics. Buying a piece of test equipment with the word avionics attached to it will run up the price. This $200 SWR Meter would be 2x or more if it has avionics, aviation, aerospace or aircraft on it. As a ham radio operator I own several of these long before I became a pilot.

[@captpsl1]

Great video, how about another video that explains the process to evaluate the entire system performance with radio powered up. Thanks

[@ik04]

Howdy Jon, I have devised a plan to mount a 20 meter wire antenna to a CH-750. It should tune other bands, too! de K4IVE

[@thedoubledmovers3411]

awesome presentation ...atleast i have learnt something

[@billtabbert8632]

Nice Thanks!

[@MrHanowski]

Thanks. I enjoy watching your clear videos. Though I'd love to have that meter to play with, I'm more interested in knowing the proper type, length, and placement of an antenna I intend to build and install in my Powered Parachute aircraft. I see kits for this where the antenna is about 24-25" long, so guess that must be about the right length? But what about placement in a Powered Parachute? Front by nose wheel? Top of roll bar? Within the framework? Does your meter answer that question, or perhaps you already know the answer? Do you know of any DIY videos for building my own antenna to replace the rubber ducky antenna of my hand-held AV radio? Thanks for any help you can offer!

[@erikdeger931]

I'm interested in knowing this information as well

[@gerryvandyk5551]

John, how did you connect the meter to the antenna cable? Is that an F to BNC adapter?

[@HomebuiltHELP]

Cable had BNC connector both ends

[@gerryvandyk5551]

Does the top of the meter have a BNC connector on it? When I look at the MFJ-259 it's got a big threaded connection. A BNC will not attach to that so what have you screwed onto that to attach the BNC cable connector?

[@HomebuiltHELP]

True, my meter has an SO239 connector so I use an adapter. Check with the manufacturer of the meter to see what connection types are available. You can always use an adapter.

[@maxasaurus3008]

MFJ just retired 😢