H. M. Motley Jr. wrote:
I have developed an intermittent problem. At times my Paragon with neither TX or RX on
18 and 15M or at other times 12 and 10 M. From looking at the circuit diagram it appears
the trouble must be in the low pass filter board where the appropriate LPF is selected by
relays which are energized by the "T" voltage which is applied to the proper
control line. I notice the two relays for each LPF are wired in series. When the
trouble occurs I hear a relay kick in and later I hear a relay stuttering. Finally it
may engage and things work properly. I notice all control lines are buffered by relay
driver U1. Has anyone had this problem and solved it? Was it U1 or the relays? I never
have this problem on the lower bands. Perhaps I should replace all 4 relays for these
two LPF's? OR maybe there is some other problem? Any suggestions would be appreciated.
when you hear relay chatter, it is usually due to pitted contact
surface, sometimes, with good polishing cloth, I clean them. Best
solution is to replace them.
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