Graham Singleton wrote:
>>Tony,
>> Get with one of the local ham radio operators that has a
>> GOOD SWR meter. Us it to "tune" the lengths to give you the best
>> (lowest swr) reflective power over the aircraft band. I have a
>> very nice curve which bottoms out about mid range.
>
>
> Its best done with any nearby metalwork in place, ie elevator push rod and
> other hardware. rudder pushrod too. They will have an effect
> Graham
>
Sure can have an effect on tuning, but worth noting that tuning the antenna will
not likely mitigate the effect on radiation pattern caused by nearby metal,
especially near the tips.
To this end, there's a web site with enormous detail on these antennas, and
author
sounds authoritative. He has developed a "meander line" antenna using foil
tape. He claims similar performance, with the meander line seemingly favoring
the low end of the band a bit. Mostly what it does is allow for a shorter
antenna, placing tips further away from annoying metal elements.
Antenna fans can browse:
http://www.nancymoon.com/antennas.htm
Regards,
Fred F.
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