Fender Super Tweed Build

Leña_Costoso

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Sweet! I'll be in the same spot tonight waiting on the filter caps. Then I'll start getting the sockets and controls attached mechanically.

The question I have is are you going to follow the drawing or why are the power supply Mains in a more safe manner? That is to say if you make the fuse the first thing seen by the black wire coming in you don't have to worry about the death cap on the ground switch. If the cat blows it'll blow the fuse.
 

Cjsinla

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Sweet! I'll be in the same spot tonight waiting on the filter caps. Then I'll start getting the sockets and controls attached mechanically.

The question I have is are you going to follow the drawing or why are the power supply Mains in a more safe manner? That is to say if you make the fuse the first thing seen by the black wire coming in you don't have to worry about the death cap on the ground switch. If the cat blows it'll blow the fuse.
Yeah, the Weber diagram has the power hitting the fuse first, right at the start.
 

Leña_Costoso

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Excellent! The Mojo diagram shows nada for the ground switch, and the schemo shows the fuse on the neutral. Go figure! I think we got the skilz-to-pay-the-bilz to fix that one though.
 

Cjsinla

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Excellent! The Mojo diagram shows nada for the ground switch, and the schemo shows the fuse on the neutral. Go figure! I think we got the skilz-to-pay-the-bilz to fix that one though.
The ground switch is not used on mine either.

IMG_0587.PNG
 

Caoimhin

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There's something beautiful about hand wired amps. I pulled my Friedman apart so I can took a look on the inside. It's like an artist looking at a painting or a gearhead looking under the hood of an old muscle car.
 

Cjsinla

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Yup. I did some more tinkering today, pulled out the Weber caps and put in the Mojo dijons. Weber is also sending me the 16uf electrolytic caps and I'll finish the board when they get here.

IMG_1449.JPG
 

Soul Tramp

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It's a good idea to elevate the resistors off the eyelet board. Having an air-gap around the resistor helps it shed heat. As resistors heat up they induce noise into the signal path. This is one of the two reason CC resistors are a poor choice.

Also, be sure none of the resistors are touching any of the caps. Resistors can get got enough to damage caps.
 

Cjsinla

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It's a good idea to elevate the resistors off the eyelet board. Having an air-gap around the resistor helps it shed heat. As resistors heat up they induce noise into the signal path. This is one of the two reason CC resistors are a poor choice.

Also, be sure none of the resistors are touching any of the caps. Resistors can get got enough to damage caps.
Good info. I'll check the resistors for air gaps.
 

Cjsinla

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Finally got the right filter caps from Weber. Finished wiring up the board and got the pots and input jacks ready to go. Next thing will be to wire the PT to all the appropriate connections.

IMG_0588.JPG


IMG_0589.JPG
 

eslover

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Looks really nice do far.

1. Does the Weber chassis have holes for stand-offs already drilled? or will the main circuit board be floating?

2. Did you decide to go with the unmodified fixed bias circuit or are you making adjustable?

Fred
 

Cjsinla

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No stand-offs. It's a fiber board with eyelets. There's a second blank fiberboard that sits below the main one. They did drill holes in the boards and chassis for sheet metal screws to hold the boards down. They lay flat on the chassis and the second board is the insulator for the main board. I'm building it to spec more or less, the bias will not have an adjustment.
 

Cjsinla

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Decided to drop the boards in, make most of the connections and do the heaters last. If you look closely you will see one of the screws at the top left that attaches the board to the case. I believe that screw may be touching the back of the filter cap lead. But, if I'm correct, that lead goes to ground anyway and should not be a problem. Am I wrong on this?

IMG_1452.JPG
 

eslover

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My eyesight must be going because I can't see the screw you are referencing from the pic. Is it possible for you to do a continuity test with a multimeter?
 

Cjsinla

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This one here. That cap goes straight to ground, that's the white wire connected at the top of the cap.

IMG_1453.PNG
 

Splattle101

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Decided to drop the boards in, make most of the connections and do the heaters last. If you look closely you will see one of the screws at the top left that attaches the board to the case. I believe that screw may be touching the back of the filter cap lead. But, if I'm correct, that lead goes to ground anyway and should not be a problem. Am I wrong on this?

View attachment 266690
Yes, it's a problem.

As a matter of principle, there should be no connections anywhere in that device that you have not planned and intentionally made. So you should fix it. Lift or move the lead, put some shrink on it, move the screw, whatever. Don't leave it.

Even if we assume for the sake of argument that this contact won't cause a problem (and that's not an assumption I'd make!), it will cause issues when the amp vibrates.

So I would definitely fix it.
 

Cjsinla

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Yes, it's a problem.

As a matter of principle, there should be no connections anywhere in that device that you have not planned and intentionally made. So you should fix it. Lift or move the lead, put some shrink on it, move the screw, whatever. Don't leave it.

Even if we assume for the sake of argument that this contact won't cause a problem (and that's not an assumption I'd make!), it will cause issues when the amp vibrates.

So I would definitely fix it.
Ok, I'll fix it.
 

eslover

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Yes, please follow what Splattle101 said.

I thought that screw was a glob of solder for the filter cap...eek.
 

Cjsinla

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Ok, fixed the cap problem and wired up the pots.

FullSizeRender.jpg
 

Cjsinla

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Got another problem. The pre-amp sockets have a metal terminal in the middle, what should I do?

IMG_1456.JPG
 


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