Here are a couple of emails I received regarding the RCS-4 noise problem:
>> I've had trouble with other relays too. The general solution is to
double the contacts via paralleling DPDT contacts. To make contact,
the circuit flows in the RCS-4 through as many as three sets of relay
contacts. To the credit of Ameritron, some of them are doubled.
However, one is not. I would suggest that that relay is source of the
noise. Only thing one can practically do is to clean it with a piece
of paper soaked in solvent.
73 de Brian/K3KO
--------
>> This is a common problem with Ameritron RCS-4 switches. There are
diodes in the switch that control the relays. (In one position + 12
volts is sent, in another -12 volts is sent, and in a third 12 volts AC
is sent.) One or more of your diodes is bad causing large switching
transients to be introduced onto the RF circuit. Replace all the diodes
and add a bit more capacitance to smooth out the rectified voltages.
Regards, John, N3HBX. >>
Cheers, Steve K7LXC
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