Fender PA-135 Head - Waht to do with it? Mod? Repair?

[spunko]

Hello friends, this time I came across with a Fender PA-135 which sounds like it was a 1 watt amp instead of a 135 watts. Really low output.

I don't know if its worth to fix this amp, I have read it sounds flat and dull for a guitar amp (I know it's a PA)
The other option would be to modify it, but I don't know how difficult it could be considering that I live in Ecuador, and there are almost no parts, I will have to order them from USA.

Is there any company that sells popullated PCBs or convertions for this amp?
Is it worth it to do anything with it? or have it just for parts?

[Helmholtz]

Hello friends, this time I came across with a Fender PA-135 which sounds like it was a 1 watt amp instead of a 135 watts. Really low output.

I don't know if its worth to fix this amp, I have read it sounds flat and dull for a guitar amp (I know it's a PA)
The other option would be to modify it, but I don't know how difficult it could be considering that I live in Ecuador, and there are almost no parts, I will have to order them from USA.

Is there any company that sells popullated PCBs or convertions for this amp?
Is it worth it to do anything with it? or have it just for parts?

First thing I'd do is check if PT and OT are ok, as these are the most expensive/valuable parts.
Amp could easily be converted to a Dual Showman Reverb or Bassman 135.

https://www.thetubestore.com/lib/the...-Schematic.pdf

[glebert]

Looks like the OT on this amp is an ultralinear type, correct? I wonder how well these do for lower powered amps.

There is a company called KLD that sells PCBs and turret board kits for tube amps on ebay. Maybe something like a Bassman or JTM45?

As far as you amp having very low output, might want to check the speaker jacks. It sounds a lot like this one. https://music-electronics-forum.com/...ad.php?t=37065

[spunko]

First thing I'd do is check if PT and OT are ok, as these are the most expensive/valuable parts.
Amp could easily be converted to a Dual Showman Reverb or Bassman 135.

https://www.thetubestore.com/lib/the...-Schematic.pdf

I'm pretty sure transformers are ok. I got it from a friend, it was working fine, one day it just dropped output. It is in pristine condition and haven't been used for years. Really low usage.
I tested the tubes in another amp and they work great, and also I put new tubes in the PA but with the same result.

Looks like the OT on this amp is an ultralinear type, correct? What are the plate and screen voltages for this? Wonder if it will be hard to make anything lower powered.

As far as you amp having very low output, might want to check the speaker jacks. It sounds a lot like this one. https://music-electronics-forum.com/...ad.php?t=37065

Yes, it is an ultralinear. I will try the speaker jacks firts, thank you very much for the link.

Maybe is there any company that sells PCBs, or turrets boards with components.

[glebert]

Maybe is there any company that sells PCBs, or turrets boards with components.

The KLD boards have components. https://www.ebay.com/itm/Turret-boar...wAAOSwqVdapyqp You would have to navigate the differences between circuits, such as tube rectifier vs the solid state rectifier your amp has.

[Helmholtz]

I got it from a friend, it was working fine, one day it just dropped output.

Such behaviour is common to many component (including transformer) and contact failures and doesn't prove anything.
I am not saying that it is likely that a transformer is defective but if so, it might impact the decision if a conversion or repair is worth the trouble and cost.

[g1]

I'd get it running (if transformers ok) and use it with pedals if you find it sounds too flat.
Start with checking power supply and tube DC voltages.

[olddawg]

I second getting it operating properly before you do anything. It should be VERY loud and clean. The next decision is to decide the application. These are basically multi channel Showmans. Probably fine for a pedal platform but don’t expect it to break up. Once you know the iron is good you can gut it and make whatever you want.

[Justin Thomas]

I'd use it as a PA. Seriously. Laugh if you like.

Justin

[mozz]

Friend had one of these, bassman drip edge model 135. Ultralinear output trans. I may have swapped out the output trans but i had mentioned JTM45 KT66's, and he said go for it. Voltages were really high so i added a 500 ohm sag resistor, he loved the sound of it when finished.