|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
69.232.72.209
In Reply to: RE: My first SS repair, I need some help posted by henrybasstardo on May 19, 2010 at 17:59:37
Got heatsink compound for the transistors? NOT RTV.
Are the output transistors PNP / NPN pairs? If so, are they 'matched'?
Some transistors MAY have a mica washer under them as well.
Ever done anything like this before?
Too much is never enough
Follow Ups:
Thanks pictureguy.
I have the mica insulators. Do I still need the heatsink compound? Use both?
My first time.
I have to keep taking firsts.
I appreciate the help
You are right on the transistors, 2NPN and 2PNP and I have them. Cool electrostatic bags. Don't know what you mean by matched? Could I have requested that? Do they match them like vacuum tubes?
The Denon is layed out so well I'm diving in.
Thanks again.
Cheers
I got the mica insulators but my gut says I do not use them on these transistors. The one I pulled out did not have them. Just compound between the transistor body and the heatsink.
I'll get under the hood tomorrow
Than put it back EXACTLY as found.
No Mica insulator, apparently.
The heatsink compound use is NOT a case of 'The Bigger the Blob, the Better the Job'. !!
use with moderation.
Transistor matching? Gain and Threshold (turnon voltage) would be my guess. If you wanted to get weird, you could match for RDon. The resistance of the device when ON. Other parameters?
I don't know.
I've seen cost advertised for such matching and it isn't much.....It can be done easily using a special o-scope setup called a curve tracer.
I haven't fixed anything in 25 years. Spent all my time in process, not maintenance of equipment.
You may want to buy a tech a cup of coffee and ask for some tips:
Too much is never enough
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: