Rockford Punch 800a2

[seankane]

Hello Perry while I am replacing the output fets on the bd15001 I thought I would pic your brain on the punch 800a2. It powers up fine does not draw excess current but has no output. Not so much as a sound or anything. Any thoughts on where to start?? The board number is PC-2038-C I dont think the output fets are faulty maybe check some op-amp voltages??

[Perry Babin]

Post the DC voltage on all of the pins of the LM339.

IC#
Pin 1:
Pin 2:
Pin 3:
Pin 4:
Pin 5:
Pin 6:
Pin 7:
Pin 8:
Pin 9:
Pin 10:
Pin 11:
Pin 12:
Pin 13:
Pin 14:

[seankane]

[QUOTE=Perry Babin;2526910]Post the DC voltage on all of the pins of the LM339.

IC#
Pin 1: 20.46 vdc
Pin 2: 5.07 vdc
Pin 3: 19.78 vdc
Pin 4: .164 vdc
Pin 5: 2.412 vdc
Pin 6: 4.92 vdc
Pin 7: 5.46 vdc
Pin 8: 4.35 vdc
Pin 9: 4.92 vdc
Pin 10: 4.92 vdc
Pin 11: 8.24 vdc
Pin 12: .001 vdc
Pin 13: 5.07 vdc
Pin 14: 5.07 vdc

[Perry Babin]

What's the voltage across R206 and R306?

Have you checked for audio on the output pins of the op-amps?

[seankane]

Originally Posted by Perry Babin

What's the voltage across R206 and R306?

Have you checked for audio on the output pins of the op-amps?

I cannot locate R206 and R306?

I have not checked the op-amp pins for audio would that be pin 8 on all of them?

[Perry Babin]

See attached.

Look for signal on pins 1 and 7. Also confirm that they all have the ±15 on the power supply pins.

[seankane]

The amp draws like 1/2 amp at idle like its not fully turning on. An amp that size should draw a little current huh? Every once in awhile something clicks on the board then when I disconnect power it clicks again but very queitly and does not do it everytime. Strange.............

[seankane]

R206 and R306 read 0.00 VDC

[Perry Babin]

Is the amp producing rail voltage?

[seankane]

Originally Posted by Perry Babin

Is the amp producing rail voltage?

Yes -56 vdc on the gate and source of all IRF640 and +56 vdc on the gate and source of all the IRF9640