Thermal Compensating Diode

[Richs_Trains]

Hello,

I have been trying to recap a 1060 and have made excellent progress as the unit sounds very good now as opposed to when I got it. My question .... I am pretty sure someone has been in here before as the outputs appear to have fresh heat sink compound on them and they are Hitachi and not labeled Marantz, whoever did it put compound on the Thermal Compensating Diode that Marantz attaches to the heat sink. My first recap, I did the same thing and could not get the bias to adjust, after I removed the compound, I was able to get a steady reading and set the adjustment. Should these diodes have compound or not, I ask because the tech who worked on this before applied it (I am not a tech, so I just took a chance before by reversing something I had changed and I don't know which is right), so compound on the diode or no? Thanks Rich

 

[Richs_Trains]

I also ask because I tried to read the values before I recapped this unit and could not get a steady reading, I also found two caps that the legs had rotted through.

 

[Richs_Trains]

pic....

 

[petehall347]

if the paste was conductive electrically it would make a difference .. if not it should be more stable than without .

 

[Richs_Trains]

Not really understanding, the paste was the same as they used on the outputs and it seems more stable, readings wise, without the paste.

 

[petehall347]

interesting ..unless the paste was too thick between the diode and heat-sink

 

[Steven Tate]

I just recapped a 2245 and found a loose mica washer when I was done. When I asked what it might be, Catrafter said it usually goes between that transistor and the heat sink. I'm not sure, but it doesn't sound like the transistor is supposed to be electrically conductive with the heat sink.

 

[rBuckner]

Marantz put grease on them and so do I. It was some other issue like a dirty pot maybe.