Mr. Yamaha
Not so much Yamaha lately...
Thanks. The silpads I have are from Aavid Thermalloy: https://www.aavid.com/products/thermal-interface/thermalsil/53-03-2gAs usual, very nice work! You are definitely inspiring changes in my own restoration efforts.
As to how tight, here is the Sil-Pad thermal performance data sheet from Bergquist showing thermal effectiveness vs mounting pressure for it's products. How that translates to how much you tighten the mounting screws. I would assume that you would mount the same as with mica and grease - tight enough to give a reasonable amount of pressure and keeping the hardware from loosening but not so tight as to distort the transistor case.
http://www.bergquistcompany.com/pdfs/techLibrary/Sil Pad Overview.pdf
I am curious as to which silpad you are using - I was planning on a K10, but looking at those charts there may be some better options from a thermal perspective, though not sure if the difference is meaningful.
They can be ordered at Mouser.
My biggest problem at the moment is the power switch. Which is unrepairable. The solder legs were so brittle that at first during other works one leg broke off. So it was still usable for a Triac power switch upgrade. When I went on that journey today two other legs broke off like they were made of cookie crumbles. Then I tried to dismantle it in order to check whether I could make new legs myself and a few parts flew across the kitchen. Very unfortunate and most likely not my day today
I was even tearing down my CT-600 and CT-810 to see whether they had similair switches, but they are quite different and can't be mounted in the same frame holes as the original.
So, I'm in desperate need of a power switch. Searched the net and the Bay, no luck so far...
The brand is Petrick and type 285/5. They tend to be used in different brands of audio equipment in the 70'ies and even other Yamaha's. Mostly CR-X00 receivers. By the looks of it, very crappy switch. Can you imagine 230V going through that thing for almost 40 years? I really think those switches were not made for 40 years +. My B-2 seems to have been used occasionally, but it has had a 'new' switch which was connected with thermoplastic connector blocks.
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