Resurrected a Customized WOPL 400

Northwinds said:
I would so be tearing my fucking hair out now. I admire your patience Scott!!
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Nah, I'm having fun and learning a great deal. Additionally, I recently acquired a 700 Series II I'd like to WOPL. So this is a good first effort. Plus, I'm retired, so now I can have fun everyday — and this audio electronics world is great fun.

I also have the 400 Series II and 3300 Series II (both have been rebuilt and upgraded, but not by me; my friend, the late Lou Dorren did the work) I bought brand new in 1980 at Pacific Stereo in Santa Cruz, CA. So I'm PL addicted.

Oh yeah, and I have another 3300 Series II preamp on the bench to go with the new 700. I'm just waiting for parts.

Life is good!
 
Now I need to test the Vu meters before I put the faceplate together. Does anyone know how to test the meters out of circuit? I know there's a way to do it, I just can't remember.
 
Scott, check theWOPLarchives, a thread there about testingmeters...
 
Yeah, I know. I saw that thread a long time ago. But I can't find it now. I'll keep looking, but it doesn't come up under any searches.
 
I think Ed said you can use a battery, not sure which voltage though
 
Northwinds said:
I think Ed said you can use a battery, not sure which voltage though
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Yeah, but it also required a resistor somewhere in the line — I think. I recall, maybe, that it was a 9 volt battery and a resistor and maybe some other component in the circuit. I'll keep looking.
 
Okay, I found the answer. It's right on the White Oak website. Off to do meters and face plate today. I'm also going to install the driver board, but as I was getting everything ready, I discovered I'd managed to lose two of the push-on transistor heat sinks. That's what happens when you have to interrupt a project for a long period of time, things get lost. I ordered a bunch form Mouser. Plus, I don't need them until I want to run the amp for testing. And, once again, many thanks to Joe. He sent off parts for the changes to the board right away.
 
Getting closer and closer. Spent part of the day assembling the face plate and meters. Both Vu's tested good. However, when I got this amp, it had those dark, dark, smoked lenses that really don't even allow you to see the meter. I tried to find different lenses, even meters, with the clear front, but didn't have any luck. So I locked them up in my machine and milled the lens off at the joint, then cut some clear glass and glued that in where the plastic had been. Also, when I got the amp, the face plate was cosmetically terrible, so I decided to paint it jet black lacquer. I put about 10 coats on, let it dry for a couple months (a must with lacquer) then sanded it with 2000 grit paper until it was completely free of orange-peel and hand-rubbed it out, so that it's like a mirror now. I sanded the bezels and painted them with some candy-apple red I had lying around. I need to swap out some parts on the driver board, as per Joe's recommendations, and then just put everything, including the relay, together and see if it works.


WOPL — 341.jpg WOAPL Buildout — 12.jpg WOAPL Buildout — 22.jpg
 
Nice work on the lens' & faceplate.
I dig your vice with it's own drip tray. Does that tray drain into the mill bed?
 
Bradrock said:
Nice work on the lens' & faceplate.
I dig your vice with it's own drip tray. Does that tray drain into the mill bed?
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Hah. The vice tray is just a holding tank sort of arrangement. Of course, just a couple strategically drilled holes would allow it to drain. But all I do anymore is 'fun project' sort of stuff. The mill is CNC driven, but the equipment and computer stuff is so old I'm thinking of donating it to the Smithsonian. Real museum piece. But back in the day. . . . . . . . .
 
I need some clarification on a couple connections before I lock everything up. Because I have an early model, I'm unable to use the WO light board for the meters. The lighting leads are the same and have nothing to do with the WO components. But the meters are, therefore, wired differently. So — are the 'OUT 1' wires from each backplane board supposed to go to the + side of each respective meter? Originally, the meters were wired directly to the binding posts. Also, in the backplane wiring instructions, it says that it's okay to use the right channel 'B+ OUT' to connect to the Watts Abundant Relay board at the B+ input. But the Watts board isn't numbered that way. I'm assuming that it's actually the J3-1 pole on the Phoenix connector. Is that correct? Oh yeah, and the White Oak instructions also say not to use the Watts relay, Zobel network, but I'm not certain what that's referring to. As far as I can see, there is no Zobel on the relay board. Am I missing something?


WOPL — 1B.jpg WOPL — 2B.jpg
 
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Yes there is a Zoebel on the relay board. If you are running backplane boards you remove the Zoebel on the relay board.
 
If you did away with the original meter leads from the binding posts use the out locations on the backplanes.
 
Which components on the board are the Zobel? Do you know, or how do I figure it out? And the OUTS on the backplanes are now my + meter leads, correct? Thanks once more.
 
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C9, C9 are the Zoebel caps. And yes, backplane outs are now speaker +...
 
Also remove R1, R2 on Don's board....they are the Zoebel resistors...
 
laatsch55 said:
C9, C9 are the Zoebel caps. And yes, backplane outs are now speaker +...
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Thanks so much for the assistance. I'm getting close to putting the testers on the thing, performing adjustments, and seeing what I've ended up with.
 
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