DX-60 function switch.

[Gerald C. Lemay]

Ask any number of people what the most common failure mode is with those
rigs and the answer would likely be: the mode switch. For some reason,
Heathkit went ahead and switched HV B+ with a puny little switch with small
contacts. Result: contact failure over time. The switch of course is non-
obtainium. A good solution is to use a relay (AC) to do the switching. You
can always replace a relay if need be but you can't replace the switch.
Another one is to repair the switch by replacing the offending contacts
with others taken from a good switch. Small screws and nuts are available
to do that. I wondered what would happen if I simply jumpered the
connection. The short answer is: nothing catastrophic! All I noticed is the
final stage draws about 8 mils during key up. Under those conditions the
final is dissipating 5.6 watts. No other "adverse" effects were noted
except for the modulator tube which was drawing 1 mil. I'm tempted to just
bypass the contacts. I'm not interested in replacing the switch. If I
really feel the need, I'll replace the contacts.

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