>> >6. I am reading that a quarter wave vertical has about 31 Ohm of
>> impedance. How
>>does it get matched to 50 Ohm coax?
>
>First, the loss in the ground system will add some R to that. You can use a
>matching network, or let your antenna tuner deal with the mismatch
>that remains.
>Again, don't worry about it unless it's a really long run of small
>coax, in which
>case it's a good time to pop for some big coax.
I have a question about this very thing. I'm running an inverted L
with the vertical portion going up about 40' or so, and maybe 1000'
of radials, mostly cut to about 66' in length each. When I put my
MFJ-259 on the coax at the shack end of the antenna I'm seeing pretty
close to 50 ohms over a relatively wide range -- from at least 1800
to about 1950. I'm using #14 AWG copper clad steel wire, which is
soldered to the center conductor of an SO-239, attached to a DX
Engineering radial plate.
Everything I read told me I should be about 30 Ohms or so at the base
and have a relatively small bandwidth (maybe 30 kHz or so). Not
complaining about having a flat match or the wide bandwidth, but I
have to wonder why I'm so out of spec with this, and if in fact I'm
heating up the ground more than I am pumping a signal into the ether.
Any thoughts on this? I'm running legal-limit power and I seem to be
getting out "OK" but not great. I'm behind a 500' high hill to Europe
(which is off the weak end of my L also), so I'm not expecting
miracles out of it but it does seem to work. Should I just "go with
the flow" or should I be looking to tweak this a little more?
Cheers,
Peter,
W2IRT
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