2.4Million ohms from input to ground pins with the black probe on input. If I reverse the probes I get no less than 3M ohms.
One of the drivers may be leaking though: on one of them, I measure ~10M Ohms from leg 3 to leg 5, while the other driver is measuring OL. The measurements are variable though.
I wish I had a spare new MIC4420CT. Ive never had to order them before.
One of the drivers may be leaking though: on one of them, I measure ~10M Ohms from leg 3 to leg 5, while the other driver is measuring OL. The measurements are variable though.
I wish I had a spare new MIC4420CT. Ive never had to order them before.
I have at least 50 or so drivers in stock, if you need one let me know. I ship fast and will have it to you faster than anywhere you could order it from. PM me if you are interested, or I can give you several links of where to order them from.
The MIC4420CT is still available but has a new updated part number for ROHS compliant of MIC4420ZT. They are cheap and readily available.
The MIC4420CT is still available but has a new updated part number for ROHS compliant of MIC4420ZT. They are cheap and readily available.
I replaced the drivers but it didnt help so much. The amp draws same current as originally did. This time I have a current limiting resistor to help protect things 
The resistor keeps my power supply at 13.5v, but with it the voltage across terminals is 8.5v. The protection LED lights for about 4 seconds then quits. When it goes off, regulated voltage quits. There also seems to be a problem with regulated voltage, as most opamps are only seeing +6v and -3.6v referencing amp ground and ~+-5v referencing RCA shields.
The positive speaker terminal has -57vDC on it. There appears to be no positive rail voltage anywhere in this amp; not even on main rects. Voltage acorss the twisted red/black wires is 57v.
The resistor keeps my power supply at 13.5v, but with it the voltage across terminals is 8.5v. The protection LED lights for about 4 seconds then quits. When it goes off, regulated voltage quits. There also seems to be a problem with regulated voltage, as most opamps are only seeing +6v and -3.6v referencing amp ground and ~+-5v referencing RCA shields.
The positive speaker terminal has -57vDC on it. There appears to be no positive rail voltage anywhere in this amp; not even on main rects. Voltage acorss the twisted red/black wires is 57v.
That appears to be defective. You may want to wait for Perry's opinion on that but I would say its defective.
I have had several bd series amp with the problem you say you have and with the voltage on the output terminal, and the LM6171 U17 being defective.
You could try removing the IC and seing if the voltage on the output terminal goes away, likely it will, and if so is probably your culprit.
I have had several bd series amp with the problem you say you have and with the voltage on the output terminal, and the LM6171 U17 being defective.
You could try removing the IC and seing if the voltage on the output terminal goes away, likely it will, and if so is probably your culprit.
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