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Old January 29th 08, 01:24 PM posted to rec.radio.amateur.equipment
Gary P. Fiber Gary P. Fiber is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 10
Default Intermittent raspy signals on ICOM 735 ?

On Mon, 28 Jan 2008 09:14:53 -0800, "Larry Gagnon"
wrote:

I have a problem with my ICOM 735 transceiver. It has done me well for 23
years now, but just recently I have noticed raspy CW and SSB signals on
receive, on an intermittent basis. This problem comes and goes, often in
long intervals and does not seem to be affected by temperature. It sounds
simply like an unclean signal with a raspy note on top of it. I am so far
unable to determine if this affects my transmit signal or not, I did get a
poor report once during this condition, but during another transmission at
another time I did not. I have the complete service manual for this rig,
but am a bit unsure where to start.

Any ideas appreciated.


Larry VE7EA



Generally this is due to the VCO trimmer caps and may be localized to
one VCO currently. I forget the switching range of the VCO but that
should be written in the service manual likely in the theory of
operation section of the service manual.

If one trimmer cap is in trouble all will be soon. Icom has been
using some ceramic dieletric caps in place of the plastic dieelectric
caps. Changing out the caps generally cures the trouble.

Gary K8IZ