Cheap Gemsound Amplifier

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Hi Chris
My marantz 510m amp power transistors is orginal and work perfect but I want STOCK THE POWER TRANSISTORS.
TO-66 DRIVERS fit to MJE15034 and MJE15035 transýstors Or Fit to MJ15022 and MJ15023 ?
You can Test this transistors to your amp?What is performance ?
AND THIS QUESTIONS CAN RAPLY MARANTZ USA ? YOU WILL ASK THIS TRANSISTORS MARANTZ USA?
Thanks
Gurol
 
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Hi Gurol,
My marantz 510m amp power transistors is orginal and work perfect but I want STOCK THE POWER TRANSISTORS.
Okay, I don't see your problem then. Just order some MJ21195 and MJ21196 and get enough to match the gains.


TO-66 DRIVERS fit to MJE15034 and MJE15035 transýstors
Yes
Or Fit to MJ15022 and MJ15023 ?
NO! Are you trying to build one? It doesn't look like you have one to look at.

You can Test this transistors to your amp?What is performance ?
I don't understand what you are asking. Performance will depend on matching and circuit design and layout.
AND THIS QUESTIONS CAN RAPLY MARANTZ USA ? YOU WILL ASK THIS TRANSISTORS MARANTZ USA?
I DON'T BELIEVE THEY WILL ANSWER YOU. I was a warranty shop and worked on these amps under warranty and well past. I could rebuild one today if one showed up.

Enough with the caps already!

-Chris
 
Sorry to resurrect this thread, however I just took a summer electronics course at WPI, so I understand alittle better whats going on inside my amp. I tested the voltage driving each channel. The Left Channel is +/-92volts however the right channel is -92volts and +164volts. Something has to be wrong here. I feel like both sides should be +/- 92volts probably lower. There is 58 volts AC coming off the main transformer. Based on these simple measurements deprived of an oscilloscope I am guessing that the problem with my amplifier is in the power supply. I do not have an adjustable power supply to test out the power stage at a lower clean voltage. Would say that my diagnosis makes sense, and if so would it be probable that i need a new rectifier circuit.

Also does anyone know what the cheapest way for me to get an osciloscope is? I have been looking at the PC ones but am not sure if I can test large voltages with them.
 
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Hi sound_prodigy,
Time to relax and study the schematic while taking measurements.

The Left Channel is +/-92volts however the right channel is -92volts and +164volts.
I can believe the 92 volts. It's been a while since I bothered remembering the rails on these. Is it possible the right channel has lost it's ground reference? Measure from the buss bar to each supply right on the capacitor terminals.

and if so would it be probable that i need a new rectifier circuit.
I don't agree. You need information, good light and a good look at things.

I have been looking at the PC ones but am not sure if I can test large voltages with them.
You need a real 'scope. No shortcuts on that. For now an inexpensive model should work fine. Just make sure it's newer, or get a Tektronix that is guarantied to work. Then, spend time to learn how it works and become comfortable with it. Then and only then are you ready to troubleshoot.

-Chris
 
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