Needing a 1970's Yamaha Engineer (employed by Yamaha)

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These were attached to the heat sink with no heat sink grease. They used silicon
 
While at Siemens we called it Germish half German/ half English
While at Toshiba we called it Japish half Japanese/ half English
No one had a clue to what was being written.
Jinglish is more polite. I've seen some truly funny translations in
Sony Broadcast manuals. When I worked for Sony Broadcast at the
1986 NAB show I would state honestly Sony had the best service
manuals of any of the Japanese manufacturers. I was an Ampex
guy but had to be good to my employer.

 
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What can you tell me about these?
I can tell you they are all 0.1uF and they almost never fail. You have a higher
likelyhood of damaging the PC board with removing parts. A Metcal iron with
a 600° tip would cause less damage.

In a later post you said they all measure 0.67uF. So what? They're power supply
bypass and would likely be fine at 0.01uF. In the nearly 50 years of maintenance
on broadcast and consumer gear I've replaced 2 or 3 0.1uF caps on Ampex VPR-3
backplane boards and 1 in an Ampec AVR-3 demod board. That's ALL of ceramic
failures in 50 YEARS. I have changed many thousands of 'lytic caps.

BTW Panasonc FC caps are very good but also check FM and FR. Performance is
the same but the seals are better. When you replace caps as part of the job you
look for longest life.

 
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You worked for Star Wars level projects, and you did this?

Dismantle a working unit, and now you need help?
You still have not stated why you needed to do it.

I am also out, this is a disaster waiting to happen.
Thank you for all the assistance you , provided, all very much appreciated.

Unit was not working. I did all this as a hobby and just wanted to see the end result, I didn't really ask for 90% of the input given and didn't steer the thread in the direction it has taken. I have tried to stop this direction several times with stating my list of questions that prompted this thread. The thread was not to repair or modify this unit it was to better understand the Yamaha documents.
 
Part number inconsistent
I don't find anywhere a cross-reference from original to these
It doesn't matter that the Hfe is highly unbalanced? One measures 35 and it's complement is at 130.
As pointed out the DCA75 PRO is a dime store piece of junk and therefor any measurements I take with it are gibberish.
I also now understand that to cross-reference the originals is BS, just put something in
 
You worked for Star Wars level projects, and you did this?
Research and Development cost very large $$$$$$$
I don't recall building something up and it worked just as wanted on the first shot, maybe more like 100 shots to get somewhat close.
The cost of a single shot on one of the Lasers is in the ballpark of several tens of millions of dollars.

Also look at it this way, if the amp blows it can always be used as a Particle Beam test target!