Hello,
I have a Heathkit guitar amp with a tremolo working intermittently. The optocoupler is working as of now, and Ive replaced all the electrolytic capacitors. I am not getting the voltages, indicated on the schematics, to the transistors, so I took out the 3 0.22uf capacitors to check them. 2 of them broke when I did, so I am going to replace them.
The ones in there are 250V. Would a 100V replacement be ok? Or 0.1uf? These are options I have on hand.
Thanks
http://ctgelectronics.weebly.com/uploads/3/1/6/6/3166248/6483742_orig.png
I have a Heathkit guitar amp with a tremolo working intermittently. The optocoupler is working as of now, and Ive replaced all the electrolytic capacitors. I am not getting the voltages, indicated on the schematics, to the transistors, so I took out the 3 0.22uf capacitors to check them. 2 of them broke when I did, so I am going to replace them.
The ones in there are 250V. Would a 100V replacement be ok? Or 0.1uf? These are options I have on hand.
Thanks
http://ctgelectronics.weebly.com/uploads/3/1/6/6/3166248/6483742_orig.png
I am still having issues with the tremolo.
I opened the photo coupler up and the bulb is consistently working but the LDR is intermittent. If I take it out of the circuit it measures fine, more light, less resistance. But once in the circuit it only sometimes works. If i leave the tester connected directly on the LDR leads, sometimes when i turn the tester on, the small voltage of the tester makes the LDR work. Ive retraced the solder and checked the potentiometers.
Ive also tried the following replacement, but turning the LED light on, the resistance of the LDR goes up rather than down. With the LED off, the LDR resistance is low, the signal is grounded and the amp is silent. So its working opposite as it should. Tremolo on, its strong and choppy, but reversed in phase. Is this possible or am I missing something?
Advanced Photonix NSL-32SR3
Blocked
I opened the photo coupler up and the bulb is consistently working but the LDR is intermittent. If I take it out of the circuit it measures fine, more light, less resistance. But once in the circuit it only sometimes works. If i leave the tester connected directly on the LDR leads, sometimes when i turn the tester on, the small voltage of the tester makes the LDR work. Ive retraced the solder and checked the potentiometers.
Ive also tried the following replacement, but turning the LED light on, the resistance of the LDR goes up rather than down. With the LED off, the LDR resistance is low, the signal is grounded and the amp is silent. So its working opposite as it should. Tremolo on, its strong and choppy, but reversed in phase. Is this possible or am I missing something?
Advanced Photonix NSL-32SR3
Blocked
Last edited:
That is physically improbable.
How are you powering the LED? How measure the LDR resistance? What Ohms numbers do you get each way?
I now have it working, with the original part, hopefully for a while, so I dont want to mess with it.
But when i put in the LED replacement, I think what happens is that the LED stays on when the Intensity knob was down all the way down. When the intensity knob is up the LED acts as it should turning on and off.