George Wright WPL-20

[robertod]

To summarize;
Items;
1. More ventilation,
2. Cap from Mouser(link sent)
3. Blue coupling cap 1uf 250v cap.(I could get from Mouser?)
4. Cap from Mouser(link sent)
5. Two resistors 1) 100k resistor Vishay PR-3 Metal films. 2) 30k resistor (I could also get from Mouser the type would be my choice, right?

I have summarized your recommendations is it fair to say I can go ahead with the upgrades.

Thanks PB

 

[Paul Birkeland]

Yeah, that's what I would do! You also have heatshrink right?  If you wanted to get some from Mouser, I would get this:
https://www.mouser.com/ProductDetail/TE-Connectivity-Raychem/SCL-3-16-0-STK?qs=pUKx8fyJudD1JeC4dGRpiw%3D%3D

 

[robertod]

Any recommendations;
Replacement on blue coupling cap
And 30k resistor.
I will get everything from mouser.
Thanks

 

[Paul Birkeland]

I'm sure there's a 30K PR-03.

 

[robertod]

P.B.
Thanks for your help.

 

[robertod]

Having trouble locating 16-18 AWG buss wire.  I've checked with local audio dealers, and electrical distributors. Any suggestions, recommendations.

 

[Paul Birkeland]

If you e-mail me your address I can mail you some in a postal envelope.  pb(at)bottlehead(dot)com

 

[robertod]

PB,
Thank you.

 

[robertod]

PB,
Thanks for all your help and patience's on all my questions!

 

[robertod]

PB

I'm getting ready to install hum pots and upgrades ( caps and resistors) I have a few questions;

I received the buss wire, I don't know if it is enough.  (could I use 16-19awg stranded and tin the ends, or solid 18 gauge copper wire?

The caps have neg-pos symbols, these caps are directional do they flow from pos---neg--> ?,

The 250v 1uf film cap does not have a - or + , is it safe to say this is not directional?

The resistors are they directional?
RESISTORS ( added pic to verify location)
Resistor- 3watts 30kohms

Resistor- 3wats 100kohms

 

[Paul Birkeland]

On the hum pots, you could also glue them just behind the grommet where the blue/red wires poke through from the OT.  I like black RTV for that job, which is available at the autoparts store.

I would not use stranded wire anywhere in those amps.  I would not use bare copper wire anywhere in those amps either.  You should only need a few inches of that wire; it's just to connect the outer lugs of the pot to the filament lugs on the sockets.  You'll need some solid core tinned hookup wire to go from the center lug of the pot over to the rest of the circuit.  I would've sent you some if I'd thought about it, but that didn't cross my mind when I mailed your envelope.

On axial capacitors, there will either be a bunch of + symbols indicating the positive side, or a big fat black stripe that looks like a continuous arrow that points to the negative section.  Another way to triple check is that most of these caps have a crimp on one end of the tubular body, and that is on the positive end.

The film caps and the resistors are non directional parts.

 

[Paul Birkeland]

Also, it goes without saying, do one amp at a time!!!  Been there, done that!  Don't want to do that again!

 

[robertod]

I understand the negative and positive sides of the cap.
Yes, for sure one amp at a time.  Thanks for answering all my questions.  I never worked on amp(s), replaced/upgrade de-solder/solder.
That is why soooo many questions.
Thanks!!!!

Congrats on the Moreplay pre-amp!!!  Another solid build from Bottlehead!

 

[robertod]

As I work on the mono blocks, I have noticed a goldish color around the different connections.
Can this be cleaned or should I leave alone.  Also I noticed the new capacitors (silver) have a plastic wrap on them.  Should I remove it?

Thanks

 

[Paul Birkeland]

The goldish color on the connections would be flux from the solder.  I would just leave it there, as it isn't all that easy to clean off, and when you do it will just migrate down into that chassis. 

The plastic wrap on the connectors insulates the metal body of the caps (which is also the negative connection of the cap) from coming into contact with anything.  I would not remove the plastic wrap under any circumstances.

 

[robertod]

Thank you for the response.  I'm learning every day.

 

[Doc B]

George's vintage surplus solder. 

 

[robertod]

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Re: George Wright WPL-20
« Reply #17 on: August 09, 2020, 04:19:14 PM »
Quote
On the 4 pin side of the blue cap, there will be a resistor to ground.  I can't see it in the photo, but if you provide the value I could give an educated guess as to what value it might be.

I copied your post that I did not answer. I have attached a pic showing the resistor your referenced that needs to be grounded. I hope the pic helps. 
The hook up wire is on its way, then I can continue the mods.

 

[Paul Birkeland]

On the 4 pin side of the blue cap, there will be a resistor to ground.

That would be this resistor.  You could probably just call it good with the hum pots and some fresh caps.

 

[robertod]

Ok,  so I'm good to go with the other mods, thanks for clearing that up.