[ICOM] Icom 756 problem, looking for advice

[John Geiger]

I have an Icom 756 (early serial number, under 2000)
that I have owned since October.  I was in the middle
of a Hellschreiber QSO on 20 meters, running about 40
watts, when the rig shut off and wouldn't turn back
on.  The fuse in the power cord was blown, so I hooked
up another power cord to it, and it did come back on
ok, but would shut off everytime it went into
transmit, even at minimum power.  I figured it was
time to send in for repairs, so I unhooked it, opened
it up, and removed the CW filter to install in my
706MKIIG while the 756 was gone.  Just for the heck of
it I hooked the 756 back up to check it on a dummy
load, and it now works fine again.  Both on the dummy
load and on the regular antennas.  The only difference
was that I now had the soundcard interface
disconnected.

My soundcard interface is a Donner's digital
interface, which I have had several before: For a
TS2000, a Yaesu FT100D, and for an Icom 706.  All
worked fine before.  This one also worked fine, but
somehow the interface and the rig together seemed to
be suspectable to RF.  If I had the computer on with
the interface plugged in, I would get distorted audio
on 40 and 80 meters.  Turning off the computer would
show a vast improvement, and I noticed with the
interface now unplugged, the audio is perfect.  I was
running the interface through the ACC port in the back
of the rig.

So I am guessing that my problem was RF getting back
in through the soundcard interface.  I don't know why
it now just got as bad as it did.  I have had rigs
shut off before due to RF, but never this severe.  Nor
have I had RF exposure blow a fuse in the power cord. 
Has anyone else had a similar problem?  Did you find
it to be a soundcard interface that was at fault?  Is
there a less RFsuspectable soundcard interface, or is
the 756 just sensitive in this way.  I have never had
these problems with any other rig or interface.

73s John NE0P
 


		
__________________________________ 
Do you Yahoo!? 
Yahoo! Mail - Helps protect you from nasty viruses. 
http://promotions.yahoo.com/new_mail