zener diode

calman46

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I may have a bad Z diode on my 2325 P700 amp board. The SM has it as a CZ-205 which tells me nothing in search. The schematic as 20.5v do they make a 20.5v zener ?
 
So you can use a 20 thanks but the Zener is ok .But I'm getting 60v where it should be 0v . I have 60v at the following points. On E,B,C of H714, H715 . At all points of R748 (tested ok) at H712, H713 . The Base of H702 is high at 10v . Nothing seems to be over heating although I don't leave it on for long. I attached the schematic, P-700 L-CH is where the trouble is. Would something open cause this ? Thanks
 

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Schematic is too fuzzy to read. As far as the zener goes, if voltage is too low on a replacement you can always put a standard diode in series with it, forward biased though, that yields an additional voltage drop of .7 volts.
 
I don't know if this will solve your problem, but there was a service bulletin issued for early versions of the 2325 that recommended the replacement of the original VD 1221M diodes in the current source and mirror circuit of the power amp (H718 & H719) to 1S1555a diodes.
 
Now R741 keeps burning , The relay was clicking before but I had no idle current . I didn't change anything thats what is strange . Any ideas
 
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