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Old August 27th 07, 04:01 PM posted to rec.radio.amateur.antenna
Technophobe Technophobe is offline
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First recorded activity by RadioBanter: Aug 2007
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Default LQQKing for 160m


"Cecil Moore" wrote in message
et...
Jimmie D wrote:
What one be the input impedance of a 10ft loaded mobile antenna on
160M?!. Gotta be less than 1 ohm.


The input impedance cannot be less than the ground
losses which are usually in the ballpark of 10 ohms.
My ARRL Antenna Book estimates the feedpoint
impedance at ~34 ohms with a radiation resistance
of ~0.2 ohms for an efficiency of ~0.6% using a
coil with a Q of 300 which is no doubt higher than
any Hustler coil. I hope John Doe likes 160m QRP -
100 watts in with less than 1/2 watt radiated.
--
73, Cecil http://www.w5dxp.com


If you just want to have 160 on the 80-10m base antenna then just add about
8ft of wire to the whip just above the coil. It ends up with about 40k
bandwidth. You lose 80 though.
I tried a mobile coil from a Proam whip to replace the 80m coil but it was
only 10k wide!!!! So I did the above.

I think you are talking about bobile antenna anyway so you could use another
make of coil as the threads semm to be all the same. but it is gojng to be
sharp!!
Cheers Dave