I was told I have RF on my audio when using my 374A so I did the usual checked
antenna for common mode tried all the tricks 1:1 balun Ugly balun even swapped
out antennas after a week of messing with this I swapped in different radio
still RF then swapped in my SB220 RF on audio gone. I guess antenna was fine so
the Alpha went to the bench changed out bypass caps on the filament supply
looked for loose screws changed bypass caps on the B+ lead plate choke looks
good Parasitic suppressors which are original look good still have RF with the
374A? THis amp has been converted to the 3cx800's running a pair fed with a
seperate filament transformer mounted on the rear of the amp both the leads are
a short run with a sheild grounded at both ends even bypassed at both ends with
.01 ceramic disc caps beating my head against the wall any ideas?
Current set up Radio Flex 5000 driving the 374A into a MBV tuner into a single
75M dipole remember no RF with the Heathkit only with the Alpha both tested at
1KW also tested with the amps grounded made no difference
Bob,kc0hfl
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