I found a bad op-amp , blown resistor, and a cap that vented through the bottom couldnt see it before so hopefully this cures the problem i let u know thanks for all the help
DO you know where i might be able to buy a couple of the dtc343tstp the ones i need are leaded not surface mount checked digikey mouser mcm cant seem to find a place to buy them or is there a good cross
They were used in Autotek and Hifonics amps. If you have any junkers laying around, they're likely to have them.
If you don't have any and can't find a source, a 2SD1302 with a 4.7k ohm series base resistor may do the job.
If you don't have any and can't find a source, a 2SD1302 with a 4.7k ohm series base resistor may do the job.
I was looking at the pwm board in this amp again while putting it back together. looks like someone put in a new timing cap for the 494 they put in a 1pf cap marked 102 its connected to pin 5 of the 494. Wondering if this value isnt right would it have anything to do with the left channel working and the right channel dead.
Just wondering before i go putting this thing back together and being frustrated when and if it doesnt work
Just wondering before i go putting this thing back together and being frustrated when and if it doesnt work
1-0 and two zeros in picofarads = 1000pf
That's a relatively common value for the power supply timing capacitor. If that was the problem, the symptoms would have likely been failing power supply FETs. It couldn't cause a dead channel unless there were two power supplies (one for each channel) and they had their own power supply driver IC.
That's a relatively common value for the power supply timing capacitor. If that was the problem, the symptoms would have likely been failing power supply FETs. It couldn't cause a dead channel unless there were two power supplies (one for each channel) and they had their own power supply driver IC.
Ok think i finally found one last problem with this amp.
I found a bad solder connection on the speaker terminal block .
So theres no connection between the terminal block and the rigt channel.
But as my luck would have it my desoldering gun took a crap heating element went bad. so when i get the new one ill finish putting this thing together and let you know
Thanks again
I found a bad solder connection on the speaker terminal block .
So theres no connection between the terminal block and the rigt channel.
But as my luck would have it my desoldering gun took a crap heating element went bad. so when i get the new one ill finish putting this thing together and let you know
Thanks again
It's generally difficult to get solder to stick to the terminals after the solder connections fail. The best option is to copper plate them. If that's not possible, you may have to drill through the board so that you can solder a wire along the top of the terminal where it 'may' accept solder. Solder it quickly. It takes very little time to damage the coating. If that fails, you can drill and tap and use a screw to hold the wire to the terminal (similar to the one below).
I wanna THANK you for all your help Perry.
Im waiting on the muting transistors but replaced some diodes and opamps.
Just powered the amp up on bench and its working !00% Thanks again
Im waiting on the muting transistors but replaced some diodes and opamps.
Just powered the amp up on bench and its working !00% Thanks again
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