merlynski
Curmudgeon Electronicist
STK-0050
Left STK (looking at front of unit)
pin1 39.2v
pin2 -41.3v
pin3 39.2v
pin7 39.2v
pin8 41.3v
pin9 40.3v
Right STK (looking at front of unit)
pin1 -1.1v
pin2 -41.4v
pin3 4-9mv
pin7 18-25mv
pin8 41.3v
pin9 1.2v
Looks like you need another fix...
Until you solve the reason for pins 3 and 7 being 39.2 volts, you won't get a relay click.
FWIW pin 7 is NOT used on the STK0050 . The pins used are 1,2,3 & 8,9,0. Inputs are 0 and 1; Power supply pins are 9 (+) and 2 (-); Outputs are 8 and 3.
If you remove the STK0050 and put 1K resistors in you can get the DC loop closed for troubleshooting without the STK.
This worked like a charm for me.
Also did you replace Q17 with new? I did not see it so stated. Post 19 lists the BE junction as 0.4 volts, not enough to be a well biased on PN junction.
EDIT: more text
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