My New Early Model PL400 w/ 4 Fin Heat Sink

[VSAT88]

BTW. I do not know if I posted images of the bias transistor fix that Lee helped me with. I would not doubt that that fix, the way he showed me to do it and the way it was done will outlast the amplifier. It is a much better way. If you need me to I can post the images.

 

[punchback]

Oh yeah! 15,000uF 100V caps and a 50A 600V bridge. I can't wait to to put them in. I've also requested an invoice for a output relay kit from Watts Abundant. A little while ago I was working on the BOM, at Mouser, for the relay board. I think you forgot a couple of caps that should be re-use from the zoeble network. Could they just be ordered from Mouser? If so does anyone have a suggested p/n?

 

[laatsch55]

.1 uf @ 100 volt Mouser part # 871-B32529C1104K189

 

[laatsch55]

Looks like a PL 400C boiard to me...

 

[punchback]

I looked and the caps on the zoeble network are . 1 100V . They looked like film caps. Looks like lots of choices like Wima. Probably just order them with the relay board BOM.

 

[punchback]

Does the WOA control board also replace this early PL400C board? Please say that it does

 

[laatsch55]

Yep...

 

[laatsch55]

Gonna have to drill a hole in the back. White Oak boards have 2 holes, in the middle, like the PL14, Pl020 boards...

 

[punchback]

I can drill a hole... Hopefully nothings in the way.

 

[Bradrock]

Member Mark Comer has done a bunch of videos on his WOPL adventures. That's how I found this place. His control board vid will give you a look at what all is in the kit.

 

[VSAT88]

Yep, I did forget to put those in on the start (the caps on Dons board) but before it was done they were caught and put in . I used one off the zobel and two I had here. Lee told you about the caps around the BR in the posts before right ? I hope you got a big ole hot iron to put that and the protect board in.

 

[punchback]

I've watched a few of Mark's videos. They're both informative and entertaining. I have a pretty decent Weller soldering station so I should be good for assembly. I also have the caps for the bridge mod in the order.

 

[VSAT88]

Awesome. They were a pan in my ass so I don't know not put them in mine. Who knows, another day ..

 

[punchback]

I got my parts in but had a little oversight. The 15000 uF 100V caps turned out to be stud mount. I've never seen them before... I hate to return them as it'll cost $12 dollars or so to ship them. I was thinking of drilling some holes and using the stud. It will fit right in with the all of the other half dozen screws on that side of the case. I also thought about cutting the stud off. Anyone else have any experience with this kind of cap? Would cutting the stud off or shortening it cause a problem? Not including the stud they're almost exactly the same size as the existing caps.

 

[punchback]

Assuming I cut the studs off right above the nuts, will that interfere with anything down the road?

 

[VSAT88]

If you don't care about keeping everything original drill a hole and bolt them in !
Edited !

 

[jbeckva]

Check the resistance stud to negative terminal, and if you have a short there then think about what that would mean if both were electrically bonded when bolting them to the chassis.

 

[punchback]

The new caps are connected negative terminal to the stud. The existing setup is negative to the chasis. So they are the same in that respect. I'm not sure if it's going to be a problem for me in respect to keeping it original... I'll have to sleep on it.

 

[punchback]

After looking at the schematic I guess bolting them to the chassis wouldn't be such a good idea. It might be OK for the +75 rail but the -75 rail would be connected to the chassis. That doesn't seem like a good idea. I guess I have to send them back .

Since I'm going to be placing another Mouser order I figured I'd get replacements for the few electrolytics that are on the, I guess, PL400C board. Based on the actual board each channel has (1) 10 uF/50V, (2) 40uF/15V, and (1) 100uF/10V. I already have a replacement for the 100uF/10V as specified by laatsch55 (470uF/50V).

On the other three I really cannot find them on the schematic from HiFiEngine. Should I just go with what's there keeping the uF that same and upping the voltage if I have to??

Alan

 

[laatsch55]

Yep, always go with what's on the board in.lieu of a documented revision or a walking talking revision like Ed Blackwood.