Hi folks - thanks for the many responses regarding "clicking" of relays.
Your responses eventually led me to section 3-5.18 of the manual which
says:
"when operating cw, a dropout delay is incorporated in the relay
circuit. The delay time is factory set to an average value and may be
adjusted via a small trimmer pot on the Control Board.... There is no
delay in other modes. Setting this control for a longer delay will help
reduce the noise caused by the relay during cw keying."
Then under section 6-10 of the manual it says:
"The buffered transmit request signal from the microprocessor at
connector 66 also drives control relay RLY 1 via D20 and Q18 to provide
a ground at the center pin of the rear panel RLY OUT connector during
transmit. In CW mode, Q12 connects C8 into the circuit to hold Q18 and
RLY 1 on between dits. This hold-in tome as adjusted by the board
mounted DELAY ADJUST pot R32".
I won't pretend to say that I understand this, but it does seem to say
that for some reason the factory does not set this pot to make the
maximum reduction in relay noise during cw keying. Rather, it sets an
average. Many of you mentioned use of external amplifiers which I do not
have and will not have in the future. Possibly this "average" setting
has something to do with external amps?
I would like to experiment and adjust the pot for quieter relay sound
but am not sure what else, if anything, this adjustment might impact. Do
any of you understand this well enough to explain what this "delay" is
for and how adjustment of the pot affects any operating characteristics
of the rig?
Thanks again for the help folks.
73/KB7OEX Tim Logan
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