Hello:

I know this transceiver doesn't "glow in the dark" like a _TRUE_
boat-anchor should, but it is getting on in years, so should qualify in
the boatanchor category by age and/or weight....

I have an Icom 751 that has begun acting very strangely. It worked
perfectly some time ago, then was relegated to a non-operating position
under the bench for about 6 months. I live in Hawaii, and the average
temperature during this time was about 85 degrees day, and 70-75 degrees
night. The humidity varied more, from about 50% to 100%, being on the
wet side of the big island.

After the prolonged time under the bench, I fired it up one day to find
that I couldn't change bands in the Ham mode. The full symptom is as
follows:

Normal function with the T/S button operation, slow and fast tuning
changes.

Normal function with the DFS button which (when pressed) allows
selecting a memory channel.

Abnormal function with the BAND button depressed. Normal operation is a
rotary selection of Ham bands with rotation of the tuning knob.
Instead, I get the frequency changing by 125 Khz with each step of the
rotation of the tuning knob, within the band that the radio starts in
(which currently is 160M band, but has been other bands on occasion).
If I select the General mode, and have the BAND button depressed, the
display changes by 1 mhz per step, which it is supposed to do. I seem
to be able to tune to any frequency I want using General mode, but only
a single band in Ham mode. (Given the transmitting range has been
"opened" I could probably transmit in General mode on the ham
frequencies of interest (haven't tried), but I really want this radio to
work like it should.

I've tried replacing the ram board with one from another unit (an Icom
751A) without change of the symptom, so I don't think it's the ram
board battery gone flat. I've reseated the flex circuit cables in their
sockets, and don't see any obvious damage to any of them.

Given it worked fine when placed under the bench, and developed this
problem during "storage", I suspect something related to the period of
time it was not in operation, (particularly moisture related) but am not
sure what the problem might be, as a similar unit (Icom 751A) in the
same location and conditions didn't succumb to this malady.

Any ideas where to start looking? I'm just about ready to haul out the
heat gun and elevate the temperature inside to about 90 degrees (F) for
awhile to see if it is affected by the currently colder area where I now
live up the mountain (daytime highs around 70-72, night times about low
60's with humidity typically in the 60-100% range).

If I can get this unit fully functional again, I have a potential home
for it, otherwise it's going onto eBay as a "tech special" sometime
soon.

Also have a number of other items going to the news groups first or eBay
soon after as the result of some upgrades (I now have both an 746pro and
756proII, so the Icom 751A, Ic-2kl and at-500 stack will be going out
for sale soon (probably individually). Will retain my other ic-2kl and
at500 for the 746pro stack and AL1200 with Mfj 986 tuner for the
756proII stack, so the shack will still be pretty full. Now if I could
only get the tower back up at the new QTH.... [sigh]

Thanks
--Rick AH7H