Replaced the power supply and audio mosfets, ir2110s drivers, and i have -2.8v DC between the speaker terminals.
I have the pot (VR 171) adjusted fully clockwise and -2.8V is as close as i can get to 0v. Where to look next?
Side note where is the +12V comming from for the Op amps?
I have the pot (VR 171) adjusted fully clockwise and -2.8V is as close as i can get to 0v. Where to look next?
Side note where is the +12V comming from for the Op amps?
Also, is it normal for the amp to draw 6 amps when i switch it into slave mode? I have nothing plugged in besides power and remote.
The supply for the op-amps likely comes from the yellow transformer in the center of the amp.
Post the DC voltage on all terminals of IC171.
Post the DC voltage on all terminals of IC171.
Ref to main ground.
1. -.007
2. -.004
3. 9.59
4. 11.93
5. -.038
6. -.039
7. -.037
8. -11.97
1. -.007
2. -.004
3. 9.59
4. 11.93
5. -.038
6. -.039
7. -.037
8. -11.97
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The voltages for the IC aren't right. Re-check the pin numbering.
No, it's not normal to have 12v on the heatsink. It could simply be leakage or a short. If you ground it, does it drain off or does it spark every time you touch ground to it?
It's not normal in other amps (this is basically the circuit used in the BAMF5500) for the 3525 to run hot.
No, it's not normal to have 12v on the heatsink. It could simply be leakage or a short. If you ground it, does it drain off or does it spark every time you touch ground to it?
It's not normal in other amps (this is basically the circuit used in the BAMF5500) for the 3525 to run hot.
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It doesnt spark but it goes to 0v and goes back up to 12 when i remove the short.
Ic 171 has -11.97 on 4 and +11.92 on 8 every other pin is essentially near ground.
Ic 171 has -11.97 on 4 and +11.92 on 8 every other pin is essentially near ground.
I need the voltages on the terminals precisely as your meter reads.
Some amps have only a capacitor pulling noise off of the heatsink. Others have a parallel 1k resistor to drain any DC. Try grounding through a 1k resistor to see if that keeps the DC drained. I'm assuming that all of the ground screws are in place.
Some amps have only a capacitor pulling noise off of the heatsink. Others have a parallel 1k resistor to drain any DC. Try grounding through a 1k resistor to see if that keeps the DC drained. I'm assuming that all of the ground screws are in place.
I am getting 6 amps now when remote is applied.
If i lift R594 it would power up normal and idle at 1.8amps with 1k resistor between chassis and ground but i loose my +12 and - 12v on IC 171.
If i lift R594 it would power up normal and idle at 1.8amps with 1k resistor between chassis and ground but i loose my +12 and - 12v on IC 171.
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Ok so it has something to do with the center grounding screw. I re-tightend it and removed the 1k resistor and im getting about .2v now ground to chassis. I have my 12+ and -12 back after re-installing R594.
I added 1K resistor from chassis to ground and now no DC on chassis which solves that issue.
I am still left with DC offset at -2.8v on speaker terminals and back to square 1.
I added 1K resistor from chassis to ground and now no DC on chassis which solves that issue.
I am still left with DC offset at -2.8v on speaker terminals and back to square 1.
If i toggle the slave switch it draw 6 amps. Once i turn on slave mode and turn it back to master it will still draw 6 amps. Its like it wont change back over. I checked the switch and cleaned it.