The 7812 regulator on the end of the board fails. It needs to be clamped to the board to help it cool.
The inductors also have a problem with the insulation wearing through and then shorting.
The inductors also have a problem with the insulation wearing through and then shorting.
Was the 7812 defective?
Are you driving a signal into the amp?
Do you have supply voltage on the various ICs on that board?
Are you driving a signal into the amp?
Do you have supply voltage on the various ICs on that board?
"Was the 7812 defective?" Don't know what the voltage should be on the regulator. I have -58.8 on pin 1, -80.3 on pin 2 & -68.2 on pin 3. That's a 12 volt drop between pins 2 & 3. So I assume it's good. Replaced it anyway.
"Are you driving a signal into the amp?" Yes. Using the same signal generator I use for everything.
"Do you have supply voltage on the various ICs on that board" Yes. + &- 15V supply is good.
"Are you driving a signal into the amp?" Yes. Using the same signal generator I use for everything.
"Do you have supply voltage on the various ICs on that board" Yes. + &- 15V supply is good.
I'll have to set this aside for now. I was looking at the input to the comparator LM311 and my probe slipped. Sure I took out the IR2113 Driver chip. I will have to order it. I'll post back when I get the driver board back up. Maybe it will fix it in the process. Thanks
The only problem I've had with this type were the regs on this version and blown FETs on a similar version. I have a 'similar' one here that I'll have to cobble together to get it working. I'll be able to help more when that's done (later today). If someone else can help, feel free to join the discussion.
In the mean time, I've ordered the LM311 and IR2113 driver. Can't do anything else till they come in.
The amp went into protect. Outputs checked leaky. Pulled the IR2113. Outputs checked fine. Replacing the LM311 just as a precaution.
Got the parts in. Replaced the IR2113 and LM311. Back to my original problem. No drive to the outputs.
I'll try to get the one I have here working well enough to get some useful info. Will be a few hours, at least.
The LM311 is powered from the ±15 supply.
The 4093 and the 2113 are powered from the 12v regulator that's grounded to the negative rail.
Are the outputs in the amp? This amp will not oscillate (at high frequency) until you drive a signal (music or low frequency sine wave) into it.
The 4093 and the 2113 are powered from the 12v regulator that's grounded to the negative rail.
Are the outputs in the amp? This amp will not oscillate (at high frequency) until you drive a signal (music or low frequency sine wave) into it.
Yes, I have +/-15V on the LM311.
The 12 reg is grounded to the neg rail at -80.3V.
The 4093 and 2113 both have -80.3V on VSS and -68.2V on VCC.
The outputs are in the amp. I drive the input of the amp with a 100hz signal from my B&K generator. Post #7 will show the signal on the input to the driver board. Pin # 8 on the board is the input. Pin #5 is ground.
The 12 reg is grounded to the neg rail at -80.3V.
The 4093 and 2113 both have -80.3V on VSS and -68.2V on VCC.
The outputs are in the amp. I drive the input of the amp with a 100hz signal from my B&K generator. Post #7 will show the signal on the input to the driver board. Pin # 8 on the board is the input. Pin #5 is ground.
I have the SMD version of this circuit with no driver board. You'll have to translate to your version.
Signal comes into the op-amp on the right (4580) and is amplified. Output is on pin 7.
From there, it goes to pin 2 of the LM311.
Output of the LM311 drives the emitter of Q3 which shifts the level of the signal to the negative rail. The collector of Q3 has a 12v amplitude square wave that is referenced to the negative rail.
All outputs of the 4093 have the same square wave as above except pin 11.
The high and low inputs of the 2113 have the same signal.
Where do you lose signal?
Signal comes into the op-amp on the right (4580) and is amplified. Output is on pin 7.
From there, it goes to pin 2 of the LM311.
Output of the LM311 drives the emitter of Q3 which shifts the level of the signal to the negative rail. The collector of Q3 has a 12v amplitude square wave that is referenced to the negative rail.
All outputs of the 4093 have the same square wave as above except pin 11.
The high and low inputs of the 2113 have the same signal.
Where do you lose signal?
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