please see my page http://www.wingsandwheels.com/page14.htm
The basic math for 1/4 wave antenna is quite simple
1/4 wave = 234 divided by frequency or to arrive at a proper antenna length.
As an example for 123.5 would be 234 / 123.5 = 22.8"....this length should
however also take into effect the distance from the ground plane to the
antenna mast tip. Considering this though an antenna cut for 118.00 would be
23.88" and one for 136.00 MHz would be 20.64 so the total difference is only
just over 3" to cover the entire aviation band and 1/4 wave antennas are
fairly tolerant and will function with fair results several MHz off from the
"ideal" antenna length.

tim

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Please visit the Wings & Wheels website at www.wingsandwheels.com


wrote in message
...
I am installing a regular rod type antenna on the wooden turtledeck of
my plane where it will attach to only wood. I got the antenna from a
friend who didn't have the attaching hardware.
Do I need to do or know anything special to attach this antenna to
make sure it operates correctly? Does it need to have a metal plate
on the inside of the airframe to attach to or does it need to somehow
be connected to the metal part of the airframe for proper reception/
transmission? Can I just use local hardware store parts?
I will be running the cable to my handheld radio.
Thanks for any assistance.
Stan
(mechanical novice)