Ok my bad .. I'll check it out in the morning when I get home.. I really appreciate the help and knowledge your sharing with me
I'm not sure what your scope is showing.
What's the 'm' trace? turn it off.
Drive no signal into the amp.
Go to manual mode and set the v/div to 5v, timebase to 5us, DC coupling, align the trace to the vertical reference.
Touch the probe to your 12v supply's positive terminal. Does the trace deflect up about 2.5v?
What's the 'm' trace? turn it off.
Drive no signal into the amp.
Go to manual mode and set the v/div to 5v, timebase to 5us, DC coupling, align the trace to the vertical reference.
Touch the probe to your 12v supply's positive terminal. Does the trace deflect up about 2.5v?
Leave the board above and the other one like it out of the circuit.
Repost the waveform on pins 3 and 4 of the LM361.
Repost the waveform on pins 3 and 4 of the LM361.
Are pins 13 and 14 of the TL074 still bridged?
What's the DC voltage on the center terminal of the output transistors? All should be about 0v.
What's the DC voltage on the center terminal of the output transistors? All should be about 0v.
Yes pins 13 and 14 on the TL074 are still bridged.. all the center terminals of the output transistors at 0 volts .. Both outer terminals of each output transistors is at 48v .. I have positive 48v on one rail and negative on the other rail on both sides of the output section as well if that helps
With both other boards installed the center terminals put off this signal.. without them installed the amp is pulling 0.9 amps on my power supply at 12v .. with the other two boards installed it's pulling 1.4 amps at 12v ... Don't know that info helps just tinkering and sharing what I see .. thanks again
Attachments
What's the resistance between pins 13/14 of the TL074 and pin 3 of the LM361?
Same as above but to pin 4 of the LM361?
Same as above but to pin 4 of the LM361?
LM361 pin 3 to pin 13 of TL074C is 129.2k
LM361 pin 3 to pin 14 of TL074C is 11.55k
LM361 pin 4 to pin 13 of TL074C is 133k
LM361 pin 4 to pin 14 of TL074C is 14.9k
LM361 pin 3 to pin 14 of TL074C is 11.55k
LM361 pin 4 to pin 13 of TL074C is 133k
LM361 pin 4 to pin 14 of TL074C is 14.9k
Does one end of R165 at the top edge of the driver board connect to pin 3 of the LM361?
If so, which pin of the TL074 connects to the other end of that resistor?
If so, which pin of the TL074 connects to the other end of that resistor?