Looking for a working early PL 400 Control board

[Brettl]

Rebuilding an older unit looking for an original board. Please email me if you have one

Thanks, Brett
artvandelay1@comcast.net

 

[laatsch55]

PL400, PL14,PL14A.,PL020 which one??

 

[Northwinds]

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

 

[laatsch55]

Was it working?

 

[Northwinds]

If your asking me Lee, my amp was not working. Figured he was just looking for a board to play with on his own

 

[laatsch55]

No special reason Ron, just wondered if you powered it on...

 

[Northwinds]

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?

 

[laatsch55]

Close to the Bias and protection circuit...

 

[Northwinds]

Close to the Bias and protection circuit...

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

 

[laatsch55]

I see the protection transistors are NTE....they're a crapshoot. And you did try powering up?

 

[Gepetto]

I see the protection transistors are NTE....they're a crapshoot. And you did try powering up?

A lot of shotgunned transistors on that board. Looks like the PO was on an Easter egg hunt.

 

[Northwinds]

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

 

[laatsch55]

Been there myself....can be awful frustrating...

 

[laatsch55]

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

Wholesale replacement of all transistors cause ya can't find the bad ones...

 

[Northwinds]

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)

 

[laatsch55]

Are you blowing fuses?

 

[Northwinds]

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

Remember, it's gutted now

 

[Gepetto]

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)

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.

 

[Gepetto]

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

Remember, it's gutted now

That is not a stock bridge rectifier, someone has replaced the original.

 

[Gepetto]

That is not a stock bridge rectifier, someone has replaced the original.

What is the part number marked on the bridge rectifier?