Thread: Yagi question
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Old January 23rd 07, 02:53 AM posted to rec.radio.amateur.antenna
Nelson Blaha Nelson Blaha is offline
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First recorded activity by RadioBanter: Dec 2006
Posts: 10
Default Yagi question

Actually, I'm sorry to say Jeff was right. For the sake of experiment
I had connected with speaker cable more than just the ground.
Basically, I connected speaker wires to the contacts on my mobile NMO
mount. The NMO mount had coax running back to the radio. I knew
transmitting like that was a pretty bad idea (illegal anyway), and that
I needed to get a proper wiring eventually, I just wanted to see if I
could observe the directional effects of my yagi.

Oddly, though, my Alinco DR-130 came with a CB MAGMOUNT when I bought
it as a kid used. It even survived my keying it attached to that
thing, and I don't think it has any protection against high SWRs. I've
always wondered how my radio survived that. Maybe it didn't... I'll
have to test it when my license comes. I only think it works now
because I tried it a while back on MURS frequencies with a radio shack
scanner.

On Jan 22, 9:05 am, "Jeff" wrote:
" I'm sure it's not much of a performer, nelson. If you're using speaker

wire as your feeder, it's going to be horribly mismatched. Your trx
expects to see 50 ohm on the antenna, and (though I'm not certain) I'd
be willing to bet that your speaker wire is either much higher or much
lower. At best, this will give terrible performance. At worst,
potentially blow up the output stage of your rig.
RG58 is the coax you need. It's cheap, sometimes free. It's the same
stuff old 10base2 networks used to be wired with, so a visit to a dump
will probably turn up loads.He did say he was using coax, the speaker wire was just a ground, which

won't really be doing very much at vhf, so that is not the problem.

73
Jeff