Foreplay III voltage question

[bainjs]

Grainger:

I went back and checked the transformer voltages just to be sure.  The voltages are:

T4 - 3.63 VAC
T5 - erratic reading
T6 - 175.6 VAC
T7 - erratic
T9 - 175.9
T10 - erratic

The voltages you requested

A1 - 114.5
A3 - 1.6
A8 - 119.6
B1 - 280.6
B3 - .001
B8 - 0

Thanks

 

[Grainger49]

Joel,

It looks like the tube in the A socket, right channel, is turned on.  The one on the B socket is in trouble. 

Have you swapped the two 12AU7 tubes to see if it follows the tube?

The 1.3V to ground sounds good for one of these LEDs, IIRC.  The 280V at B1 versus 114V at A1 says the B tube is off.  Right now just swap tubes. 

If the problem doesn't swap channels rewet the solder on B1, B8, B6, T32, T31 and T39.

 

[bainjs]

I swapped the tubes and it did not make any difference in the voltages.  I will resolder the terminals now and let you know.

Thanks

Joel

 

[bainjs]

I re-soldered the terminals, however, it did not make any difference.

Thanks

 

[Grainger49]

Joel and I are getting together to troubleshoot this.

Joel is 1/2 hour away and we are going to have lunch, work on the FP III then, I'm guessing, listen to the FP III.

 

[Grainger49]

We beat it!  Joel is listening to his new FP III now.

 

[Paul Joppa]

What was the problem (besides the gas regulator tube - I suppose a solder joint...)?

 

[Grainger49]

Admission here, we don't know.  We did a lot of things, rewetting a number of solder joints and then it worked. 

The OD3 was fine as was the right channel.