Hi to any out there owning an Ameritron QSK5 T/R switch.
I have been experiencing a rcv problem using the QSK-5;
the rcvr would seem to go partially "deaf". Exercising the
QSK power switch, to jiggle the relays, does clear the
problem for a time, then it returns?
I presume this means "dirty" relay contacts. There are five
pairs of relay double throw switches. Three of them are in
parallel on an open frame relay with another pair in what
appears to be a "sealed" PCB relay package. This pair
in the "sealed" relay unit goes in series with the usual
xcvr to amp input RF connectors, so when active, places
the transmit RF signal from the xcvr into the amp input
terminal. I presume this is a reed type relay, not sure,
but is fairly small unit. I assume whatever sort of relay
switch is in this small pak does not have "dirty" contacts.
The open frame relay, with three of the dpdt switches is
a bit awkwardly placed, at least for contact cleaning. I
can get a bit of linen paper between the contacts nearest
the Amp Out connector end of the unit (and assume these
contacts switch the amp output power connector between
the antenna and the mysterious relay contact point labled
"RF IN"). And the next pair in on the open relay must be
the DP switch between the Antenna terminal of the QSK5
and what ever "KA2" is. And the third pair of contacts
must be to ground the equally mysterious circuit point
designated "KA1".
The A and F relay points must connect to the A and F points
shown on the QSK circuit diagram; I am guessing that KA1
and KA2, one or the other must go over to points L and/or H
of the circuit diagram. Unfortunately there is no connect "code"
shown, hi.
Any suggestion for how to clean the inner two pairs of relay
contacts of the open frame relay. Has one of you with the
QSK5 unit also had this problem/ need to clean contacts,
or is it just my tropic climate?
73, Jim KH7M
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