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Bruce in Alaska
 
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Default SSB reflected power?

In article ,
"Keith" wrote:

OK, more details on the system. Icom 802 going to the AT-140 automatic
antenna tuner. Yes, the tuner is working, you can hear the relays clicking
when you press the "tune" button or transmit. The antenna (made by the
Digital company... I should have specified!) is on the flying bridge, as is
the tuner. The tuner is about 3' from the antenna. The antenna is right
behind and above the pilothouse. The base is maybe 10' from the wheel and
electronics, etc.

2" copper foil runs from the radio to the antenna tuner, and splits off
about midway and goes to the bilge, where it's connected to a dynaplate. I
plan to add some more foil and connect the fuel tanks and run some radials
down there as well. Lets see: the run from the radio to the antenna tuner is
about 25', and the run from that one to the dynaplate is about 10'.

No, we didn't check the SWR. I wanted to add more foil and some ferrite
cores to see how this helps out. I wanted to do the things I can do rather
than pay the tech all those $$$ for basically grunt work. I can call him
back out whenever.

No, my hand doesn't burn when transmitting! ;-)

Yes, I believe the VHF cable needs replacing. It's old and probably cracked
somewhere along the line. The Link 20 DOES have the sheilded cabling as
Larry described, but the ground foil runs right alongside in the same chase.
I don't think I connected the sheild to ground though... I'll fix that.

--


Keith


Well Keith,
Sounds like the rest of the folks have chimed in on your problems, and
nailed down the fixes. I really like Gary's comments, as he seems to
have a good handle on what is going on. Larry is ok for some things,
but Larry, 100 watts will certainly burn you from the grounded Micholder
button on the mic during transmit, If the ground system isn't good
enough to support the antenna at the freuqency of transmission. The
Radio Ground becomes part of the antenna, and you then also become part
of the antenna, and if you are lower impedance than the ground system
you get the Rf Current instead of the Ground system. It happens, not
alot but it does happen, less now with autotuners, but it still happens.

Keith, you need to get a new Marine Radio Service Tech! One who actually
has been around since BEFORE autotuners existed. The guy you had was an
idiot, and needs to go back and get a refund on his training. You should
also get a refund on anything you paid him, BIGTIME. I know that
COMPITANT Marine Radio Service Tech's are hard to come by, as most have
left the field because there just ins't any money in the Service end of
the business anymore, but look around some more and find one.


Bruce in alaska
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add a 2 before @