The Smoked 400

Had to go to a well just outside of town and get me a quart of the FINEST whitesplooge remover there is. Its called "condensate". This is what condenses out of a natural gas stream when it cools on surface. I dont know exactly what's in it that attacks the white grease so well, but I've seen assays that show all the "anes" to decane and above. Extremely flammable, like liquid dynamite. Used out in the driveway only. At the 90 deg it is outside today, the stuff will evaporate almost as fast as I pour it. I'll go through that whole quart in 10 minutes cleaning 4 heatsinks. Just brush on and its gone.
 

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R76 in, now for the 2 pico B- fuses...
 

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Confirmed B- picos are history..
 

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I have a few picos...
 

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New picos in..
 

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After an output short, you should check the 1/4 watt resistors on the back planes, I've had some fail along with an emitter resistor two. Luckily no emitter resistor failures..
 

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Perry it was a pain the ass. I used 2 soldering irons after doing the solder sucker and my problem was the grease on the mica insulators. they wouldn't just drop out. Had to have a 3rd hand so Jani was drafted. After that it went well....
I'll leave these backplanes in for now.

I attached a heavy magnet so they would fall out. But then again, I didn't use the whale snot. I used the Sil pads
 
10 minutes. Clean heatsinks.
 

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Bottom row soldered in. Time for the DBT and variac...20190803_192403.jpgu
 
Bright bulb, rail voltage would not go over 4 volts...
 
Good luck with the repair. I can see quite a few things need to be checked. Good thing there is some protection in there. Were you clipping the 400 when it blew?
 
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