Power transistor help

"Ideal T-strippers " should be a porn site. My I.P.A. alcohol comes in a keg. Currently it's Goose Island. I use 99% alcohol to clean solder flux that is not water soluble.

My suggestion for less aggravation installing outputs is to align the pins on each output to it's future location on the backplanes before installing the backplanes. Lay them out on the bench in 4 columns.
 
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Joe,
Guess I just need to clean, c;ean, clean, etc.
Is there any reason that I cannot use Silicone Hook Up Wire of the correct AWG. I have tons of wire from my drone days!
 
gary33030 said:
Joe,
Guess I just need to clean, c;ean, clean, etc.
Is there any reason that I cannot use Silicone Hook Up Wire of the correct AWG. I have tons of wire from my drone days!
Click to expand...

That wire will not withstand soldering very well and looks like crap. I was with the Army UAV program for 17 years.
 
Hi Gary
Yes it is just a matter of clean, clean, clean. If your solvent is dirty from the flux residue washed off, it will dry on the board and redeposit flux residue everywhere. You have to get to the point where your solvent is basically free of residue to restore the original shine of the solder mask.

Like your dishwasher, if the rinse water is dirty, your dishes will come out dirty

On Silicone wire, you can, but like Perry says...

It is great for my soldering pencil wire...
 
Yup, usually both sides because the flux laden alcohol gets on both sides and leaves a flux residue as it evaporates and dries. Takes a good amount of work and alcohol to clean boards well.
 
First Good morning, everyone...
Last night I installed my new repaired backplanes boards. (Thanks again Joe). Installed first roll of transistors, did all the electrical checks and everything passed with flying colors. Installed second roll of transistors. did all the electrical checks but this time also adjusted the Bias voltage. Left channel set to 0.350, right channel set to 0.351. All is good so far. Third row installed. Everything measures good. Installed fourth row. Measured amp again but this time have no Bias voltage.
Voltage off the capacitors: 161.0 volts
No fuses blown including fuses mounted of circuit boards.
I have 15 volts +&- on the control board.
Protection relay closes after about 3 sec. and stays closed unit power down.
0.00 volts on the outputs binding post.
Normal or is something wrong?
 

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Take the last row back out and verify that the amp is still within spec, and then I would FIRST, clean the hell out of the control board, and then clean it again. I still see some pretty rough soldering going on there.
 
Yep, if you are using more than 2 fingers installing the trans/SilPads, you are wanking on them to hard. Inspect the SilPads and mounting area
 
Very easy to tear a Sil-Pad, how did the DBT respond when you brought it up?
There is a good chance that is where you will find the culprit. Sniff's suggestions to proceed
above are right on. Take it slow, you are getting close. I always check for shorts, (continuity)
before I bring up a row, test each transistor after I install it.
 
DBT responded correctely. Bright for about 2 seconds and dims almost completely. Have not had the time yet to pull out the transistors and inspect. Will keep everyone in the loop.
 
Have you measured C and E voltage on the bias transistor?
 
Id assume to test the C and E voltage, the amp is powered up. Red lead on C from meter? Black lead on meter to copper bus? And than the same for E terminal?
 
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