In article ,
Wayne.B wrote:

I've had an Icom 802 SSB with AT140 tuner installed on the boat for
over 4 years now. It uses the more or less standard 23 ft whip
antenna and has the same ground system that the old SSB had which is
alleged to be a copper strap running down to the bonding system. It
has worked fairly well up until recently but now seems to be
transmitting weakly and the control panel is indicating a high SWR.
Nothing has changed as far as I can determine and all connections seem
to be tight and corrosion free. I'm suspecting that the tuner is not
working properly but other than buying and installing a new AT140, I
can't think of any way to trouble shoot this issue.

Any suggestions?

When you hit the Tune Button, on the radio, do you hear the Autotuner
relays clicking as the tuner does it's thing? If Yes, then suspect the
RF Ground. If No, then open the tuner, and see if it is still powered by
the radio +12 Vdc buss. Yu can also check the coax cable between the
radio, and tuner, by putting a dummy load, at the tuner, and a SWR or
Wattmeter at the radio, and see if the coax is degraded.

--
Bruce in alaska
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