Help needed on Extended Foreplay III upgrade

[docbob52]

I am getting some bad voltages and resistance measurements:

H1--  16v instead of 26.5v

Term 12--  95V instead of 150v resistance 53 ohms instead of 83

Term. 15--  10.8v instead of 75v, resistance is 2.5 meg and climbing instead of Infinity

Term 21-- 93v instead of 150v  resistance 53k instead of 83k

Term 31--  19v instead of 75v  resistance is 7megs and climbing instead of Infinity

Term 32-- 93v instead of 150v  resistance is 53k instead of 150k

The LED on socket A does not flash on momentarily, as the B socket does.

Power transformer voltages on terminals 9and 9 air 96v.  I am not sure if this is correct, but seems like it should be 165 volts as in the original Foreplay III

I have traced wiring and have not solved the problem. I would check the A and B, but the socket voltages are not specified in my 2006 manuals. 

All help is appreciated.

 

[Paul Birkeland]

What do you have at "I" on each side of the center PC board?  How about Kreg?

-PB

 

[Paul Birkeland]

So you have no LED's lighting up on the outside boards?

I'd always start with the basics:

Are the 2N2222A and 2N2907 transistors in the correct positions (they look the same)?
Are the MJE340's and MJE350's in the correct positions (they also look the same)?
Are the LED's oriented correctly on the outside boards?

Your shunt regulator appears to roughly be working, but it's regulating 50V below where it should be, and you have the voltage coming in to make this work.  R3 and R4 set up this voltage, I would verify the resistances with the power off, R3 should be R3 should be 2.49K, R4 should be 147K.

 

[Paul Birkeland]

H1 and H2 are biased up by the high voltage regulated power supply, which is running low.

If the LED's are installed upside down, I wouldn't bother removing them. 

I would try reheating all the center pins of the MJE350/340 transistors, as they tend to sink a bit of heat. 

You can, to some degree, confine your troubleshooting to the center socket.  Can you give me the voltage present on either side of each 2.49K resistor on the center C4S board? (IIRC that's R3)

-PB