+0.675 is the reading I'm getting to reference of the picture. When I switch the Leeds around the ather way shows 0L
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It's OK.
You need to follow the circuit back from the cathode of that dode, pin 8 of the opto-coupler to see where the circuit to the power source feeding pin 8 is broken.
If I'm not mistaken, the source of power is the power transformer and the diodes in the corner of the amp near the 494.
You need to follow the circuit back from the cathode of that dode, pin 8 of the opto-coupler to see where the circuit to the power source feeding pin 8 is broken.
If I'm not mistaken, the source of power is the power transformer and the diodes in the corner of the amp near the 494.
If you can't find the source, I'd suggest that you connect a dummy load to the speaker terminals to see what gets hot.
What would be a good load to hook up? I have a old subwoofer voice coil the coil good but the cone is bad
The coil will likely burn if the 22v holds unless it's water cooled.
Do you have a current limiting resistor?
Do you have a current limiting resistor?
I hook up a subwoofer 4 ohms . I soon I hook it up. The fans cut off. Led400 is still on. D301 and d302 are not on. Nathing getting hot outside of the resistor from earlier that burnt off and also the two op amps by led 400 are harm too the touch.
Went and got a high output light to see through the board better. Was able to follow the Trace from resistor that burnt off the board earlier, back to the left corner of the amp. (RCA input face you) the Trace comes from REC104, REC107,REC105 AND C130
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When you connected a sub, the DC likely dropped to 0v and that caused the fans to switch off.
In the photos I have, someone replaced the resistor that melted off of the board in your amp with a large through-hole resistor and siliconed it in place. I'm not recommending this as a solution but this may be a problem in these amps. Are the pads next to it in parallel with the ones for the hot resistor?
With nothing connected to the speaker terminals and no power applied, what's the resistance across the speaker terminals?
In the photos I have, someone replaced the resistor that melted off of the board in your amp with a large through-hole resistor and siliconed it in place. I'm not recommending this as a solution but this may be a problem in these amps. Are the pads next to it in parallel with the ones for the hot resistor?
With nothing connected to the speaker terminals and no power applied, what's the resistance across the speaker terminals?
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