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New to me Marantz 2275 (with issues)

Steven Tate said:
One is PNP, and one is NPN. They each have their own testing regimen - outlined in the link above. You should be doing six tests on each one, but different polarities for PNP and NPN. Use the Diode Test mode on your DMM.
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Ok here are the 6 tests of each.
 

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Do you have your DMM in Diode Test mode? Your results should all either be OL (no continuity) or something around 0.5-0.6V forward voltage drop.
 
I'm just not understanding the test results. Do you have a diode laying around anywhere that you can test? With the leads attached one way, you should get OL, and the other way should give you roughly 0.6V. I'm not sure why you are getting readings of 1 or 400.
 
Steven Tate said:
I'm just not understanding the test results. Do you have a diode laying around anywhere that you can test? With the leads attached one way, you should get OL, and the other way should give you roughly 0.6V. I'm not sure why you are getting readings of 1 or 400.
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I’ll test the new output transistor I got with the DMM and let you know what happens shortly
 
Steven Tate said:
I'm just not understanding the test results. Do you have a diode laying around anywhere that you can test? With the leads attached one way, you should get OL, and the other way should give you roughly 0.6V. I'm not sure why you are getting readings of 1 or 400.
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New transistor measures higher at 576 and 578 for the blk to base red to collector, blk to base red to emitter. All other test points still show 1
 
Steven Tate said:
I'm just not understanding the test results. Do you have a diode laying around anywhere that you can test? With the leads attached one way, you should get OL, and the other way should give you roughly 0.6V. I'm not sure why you are getting readings of 1 or 400.
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Im only getting an open lead if I have both the red and black leads touch the collector
 
I guess I don't know how to evaluate those results. They sound more like HFE readings. Maybe something about that brand of DMM. I'm not sure. But Diode test function should give you a voltage drop reading, and that is usually around 0.6V for a single diode or transistor junction.
 
Do me a favor and on the NPN output, put the red lead on the base and the black lead on the emitter in diode test mode. What reading do you get?
 
Steven Tate said:
Do me a favor and on the NPN output, put the red lead on the base and the black lead on the emitter in diode test mode. What reading do you get?
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according to manual of this DMM its an open circuit when 1 is displayed
 

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xalara76 said:
460
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OK. Maybe that’s .460V drop. If that's the case and 1 is open, then they would seem to test good. Next would be to pull the drivers, H713 and H714 and test them. Once you have tested the outputs, it's a long slog to pull, test, and put back transistors. Assuming there isn't a wiring problem, it seems something is blown on the amp. It could be transistor, a diode or a resistor. Less likely, it could be a cap.
You said earlier that if you put the right amp on the left side, it worked. Did I read that right?
 
Steven Tate said:
OK. Maybe that’s .460V drop. If that's the case and 1 is open, then they would seem to test good. Next would be to pull the drivers, H713 and H714 and test them. Once you have tested the outputs, it's a long slog to pull, test, and put back transistors. Assuming there isn't a wiring problem, it seems something is blown on the amp. It could be transistor, a diode or a resistor. Less likely, it could be a cap.
You said earlier that if you put the right amp on the left side, it worked. Did I read that right?
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Correct. Recapping and adding new transistors/ diodes to the right amp board. Cant find H719. Almost done !
 
I guess I'm a little lost about symptoms. On one hand, the right amp works if you put it on the left side. That would indicate the right amp is good. On the other hand, if you criss cross the RCA cables from Pre to Main, the left side works either way. That would usually point to a bad right amp. That's why I wanted to test voltages to the board, to make sure it wasn't a wiring issue. That all seemed good. So, I'm a little lost at this point.
We know for sure both speakers are good?
 
Steven Tate said:
I guess I'm a little lost about symptoms. On one hand, the right amp works if you put it on the left side. That would indicate the right amp is good. On the other hand, if you criss cross the RCA cables from Pre to Main, the left side works either way. That would usually point to a bad right amp. That's why I wanted to test voltages to the board, to make sure it wasn't a wiring issue. That all seemed good. So, I'm a little lost at this point.
We know for sure both speakers are good?
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just recapped right amp board problem still persits but i wanted to recap unit anyways so who cares at this point about that. Going to take left amp and place it on right side. If thats no bueno then preamp is suspect im assuming
 
Steven Tate said:
I guess I'm a little lost about symptoms. On one hand, the right amp works if you put it on the left side. That would indicate the right amp is good. On the other hand, if you criss cross the RCA cables from Pre to Main, the left side works either way. That would usually point to a bad right amp. That's why I wanted to test voltages to the board, to make sure it wasn't a wiring issue. That all seemed good. So, I'm a little lost at this point.
We know for sure both speakers are good?
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Any reason why i get both channels on dubbing out but not on headphones?
 
Orwell84 said:
Nice receiver, I hope it sings for you when you're done.
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Thank you ! I hope so too haha im determined
Steven Tate said:
I guess I'm a little lost about symptoms. On one hand, the right amp works if you put it on the left side. That would indicate the right amp is good. On the other hand, if you criss cross the RCA cables from Pre to Main, the left side works either way. That would usually point to a bad right amp. That's why I wanted to test voltages to the board, to make sure it wasn't a wiring issue. That all seemed good. So, I'm a little lost at this point.
We know for sure both speakers are good?
Click to expand...

Okay I took the left aml board put it on the right side. No sound until volume pot is turned up to half way ! Interesting indeed
 

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Steven Tate said:
I guess I'm a little lost about symptoms. On one hand, the right amp works if you put it on the left side. That would indicate the right amp is good. On the other hand, if you criss cross the RCA cables from Pre to Main, the left side works either way. That would usually point to a bad right amp. That's why I wanted to test voltages to the board, to make sure it wasn't a wiring issue. That all seemed good. So, I'm a little lost at this point.
We know for sure both speakers are good?
Click to expand...
Plugged it all back up, turned volume up half way still no right channel on right side.. this is WEIRD ! Lol
 
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