I installed a temporary 20K pot in place of R217. Yes at 3.3k the amplitude of the clear square on pin 8 goes to about 7v. I didn't turn higher than 3.3k though.
How much amplitude does this circuit need?
How much amplitude does this circuit need?
I'm not sure but it needs to be high enough to make pin 10 start producing pulses. I wouldn't let the amplitude increase to more than the supply voltage for the 4093.
I cant get it higher than about 7v. The supply voltage on the 4093 is 12v. I forgot to mention this, but yesterday slipped and messed up the parts CD4093. I then went back to the amp's original 4093. I think I might need to order a new CD4093 this time.
There should be a resistor between the output of the LM311 and the positive PS pin for the LM311. What is it?
R214. That’s a 2.9k resistor. I actually tried lifting that resistor but it did not increase amplitude to the mpsa92 emitter.
Do you have a signal generator that's isolated from the mains power (battery operated/handheld)?
I dont. I could probably use a tablet as a generator if its just for the RCAs. Otherwise everything is non-isolated. I can disconnect the RCA shield from my generator.
Are you thinking I could use a frequency generator attached to pin 8 of the 4093 instead of the LM311/MPSA92? What would be reverence? Negative rail? What would be the frequency?
Yes. Before going through any other resistor replacements/mods, I just want to try to drive a strong signal into pin 8.
You can use the added windings to generate a drive signal that floats and can be referenced to the negative rail.
Have you seen it in the tutorial?
You can use the added windings to generate a drive signal that floats and can be referenced to the negative rail.
Have you seen it in the tutorial?