Fender BJr repair

syscokid said:
The resistor that you linked to is a carbon film. I would suggest a metal oxide resistor instead. In your pic, the resistor to right of “old toasty” is a metal oxide resistor.
Perhaps like this:
www.tubeampdoctor.com

Resistor 2.2kOhm/2W, 2% tolerance!

Metal oxide film resistor 2.2kOhm/2W, 2% tolerance!
www.tubeampdoctor.com www.tubeampdoctor.com

Since your amp is about 23 years old, Amp Mad’s suggestion to replace all the electrolytic filter caps is probably a good idea. Especially if you plan to keep your amp for a long time.
Click to expand...
Are you going to add anything to this parts list?
I could only get metal film or carbon comp resistors.
Ordering everything from 1 place to save shipping charges.
 
Amp Mad Scientist said:
I couldn't get the 500V caps in UK.
So you are back to the stock 450V caps.
I couldn't get wire wound or metal oxide resistors so you are (so far) metal film.

He has to buy a pack of 10 to get 1 metal oxide resistor.
So I said screw that.
Click to expand...

I did order a set of 500V caps about a week ago, likely paid too much for them and still waiting for those to arrive. I'll share a pic here to check with you that they're the right stuff, if they ever get here..

If not, I'll be happy with the 450V too.
Many thanks!
 
STRefugee said:
I did order a set of 500V caps about a week ago, likely paid too much for them and still waiting for those to arrive. I'll share a pic here to check with you that they're the right stuff, if they ever get here..

If not, I'll be happy with the 450V too.
Many thanks!
Click to expand...
OK go with the 500V caps, that is better.
I will scratch the caps off the list.

Where did you order those from?
How much did you pay for them?

I noticed the price of caps was pretty high in UK.
I was going to order from TAD, but they were out of 47uF caps.
They didn't have any 2 watt resistors either.
 
@Amp Mad Scientist I understood that's what you were trying to do, and that makes a lot of sense. Glad you find the price reasonable and thanks for pointing out about the +_ poles.
Had I known about Mouser UK I had gone for the 450v too.

When I'll get onto the job I'll check with you before soldering.
So I still need to get some "wick" and control cleaner. Any recommended brand there?
And What "fuses" do you think i may need pls?
Cheers!
 
STRefugee said:
@Amp Mad Scientist I understood that's what you were trying to do, and that makes a lot of sense. Glad you find the price reasonable and thanks for pointing out about the +_ poles.
Had I known about Mouser UK I had gone for the 450v too.

When I'll get onto the job I'll check with you before soldering.
So I still need to get some "wick" and control cleaner. Any recommended brand there?
And What "fuses" do you think i may need pls?
Cheers!
Click to expand...
Take the fuse out of the amplifier.
Diameter? Length? Rating type?
Post pictures?
 
Amp Mad Scientist said:
do you have any RTV / silicone cement or can you get that at a hardware store?
Do you have 91% isopropyl alcohol or can you buy some at the chemist shop / drug store?
Do you have Q Tips and paper towels?
Do you have rubber gloves?
Click to expand...
RTV/silicone cement? Will have to look that up. What is it used for?
isopropyl alcohol? What is it for?
Q tips?
I'd never thought of those things. Pls do tell me what They're for.
Thanks again
 
The alcohol we can buy at the grociery store and some grociery store have the silicone sealer also.But you might have to go to hardware storeScreenshot_20250214_101840_Gallery.jpgScreenshot_20250214_101852_Gallery.jpg
 
STRefugee said:
RTV/silicone cement? Will have to look that up. What is it used for?
isopropyl alcohol? What is it for?
Q tips?
I'd never thought of those things. Pls do tell me what They're for.
Thanks again
Click to expand...
The cement is used to glue the capacitors down to the board.
This is what Fender uses.
Otherwise, the caps can break off the board from vibration.

Isopropyl alcohol (91%) used for cleaning flux off of the circuit board.
Q tips, paper towels, toothbrush very handy for removing the flux from the board.
Buy this at the drug store / chemist shop, it's cheap.

Gloves: just to keep your hands out of the flux and alcohol.

Solder wick with rosin flux: pulls the solder out of the holes for parts replacements.
Rosin is the best flux for doing this job it works the best.
After you suck the solder out of the holes, clean off the flux with 91% alcohol.

Flux is conductive. That's why we clean all the flux off the board.
I would not recommend that you leave the flux on the board.
But rather clean it up nice and neatly.
 
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Amp Mad Scientist said:
You may find that tool very difficult compared to solder wick.
Especially for taking solder out of plated thru holes in printed circuit boards.
Click to expand...
Well funny, that’s exactly what I find it good at, sucking all the solder out of a plated through holes. :unsure:
That tool is over 40 years old and still works great. In my younger working days I’ve used it to remove 40 pin DIPS from circuit cards.

But, for the REALLY big jobs…

IMG_2025-02-14-132339.jpeg
 
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