[ICOM] 756 pro III noise

[Jaime Gomez]

This afternoon I was testing one of the new antennas for 40 mt, all of a
sudden I started hearing a very strong (s9 in the meter) pulsing noise, it
pulses at about 15 cycles per second, after a lot of checking I found that
the noise is produced in the radio, it is present without any external
connection to it and doesn't matter which power supply connected, I tested 3
different power supplies, the noise is definitely in the radio. I connected
another one and no noise.
Anyone who has experienced something like this? Any hints about where to
check?

Appreciate any help, because it will be quite difficult to re-export it for
repairing and CQWW is close.....

-- 
Jim, HK1N