Looking for a working early PL 400 Control board

I just gutted a Series 1 400 and have the control board, I left the wires long when I removed it, looks to be a 14

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If your asking me Lee, my amp was not working. Figured he was just looking for a board to play with on his own
 
No special reason Ron, just wondered if you powered it on...
 
You guys told me the bridge rectifier looked iffy, no lights no nothing on power up so I gutted it for a future WOPL or sell it for parts, have not decided

Looks like these need replacement on my control board. I don't see anything else that looks bad

Here is a shot of each one (fried on both sides/channels), what are they and what is their purpose?

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laatsch55 said:
Close to the Bias and protection circuit...
Click to expand...

and???? What do they do and what might have been the cause of their demise? Joe said some of the transistors between the heatsinks somebody put in were incorrect

I would love to test if the tranny is good
 
I see the protection transistors are NTE....they're a crapshoot. And you did try powering up?
 
I only plugged it in standalone Lee, no meter lights came on so I figured it needed to be gutted anyway

What do you mean by shotgunned Joe? I see no holes blown in the board LMAO!!! Just those two areas I imaged looked bad under the magnifying glass
 
Been there myself....can be awful frustrating...
 
Northwinds said:
I only plugged it in standalone Lee, no meter lights came on so I figured it needed to be gutted anyway

What do you mean by shotgunned Joe? I see no holes blown in the board LMAO!!! Just those two areas I imaged looked bad under the magnifying glass
Click to expand...


Wholesale replacement of all transistors cause ya can't find the bad ones...
 
How do you test the tranny to see if it's good? I have a digital meter finally. What setting do I use and what are the test points for the bridge rectifier? Which hole do I plug the positive probe into on the meter? There is 2 besides the common ground (black)

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It toasted the power line fuse instantly, the speaker line fuses were fine

Remember, it's gutted now

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Northwinds said:
How do you test the tranny to see if it's good? I have a digital meter finally. What setting do I use and what are the test points for the bridge rectifier? Which hole do I plug the positive probe into on the meter? There is 2 besides the common ground (black)
Click to expand...

You unsolder both of the 2 AC input leads from the transformer to the bridge and tape them off to insulate them, replace the AC mains fuse. Power up the amp again. If the mains fuse does not blow, you have a good transformer and the bridge is toast.

If you still blow the AC main fuse, your transformer is toast.
 
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