Schematic or Layout needed - Oahu 260K "Sunshine" / Supro 1614B Spectator

[sbolt]

Hey All,
Last weekend, while at a party a friend of a friend brought an old Oahu amp and literally gave it to me …. He knew that I play guitars and like to fiddle with amps...I know how to be safe and discharge capacitors etc before poking around… However, it looks like someone else was in there and replaced some components and I'm not sure if they used the correct values. Unfortunately after an exhaustive amount of research I cannot find the schematic for it. Can anyone point me in the right direction?

**It is the 12AX7 preamp version that I am looking for.

 

[Supertwang]

To start with compare the circuit to a Champ schematic. Where is it similar? Where is it different? I usually use the Champ/Princeton schematic as the “default” when working with oddball single ended amps.

 

[Supertwang]

There’s an amp tech is south eastern Indiana that’s widely accepted as the “Valco Man”. Supposedly, he’s the authority on everything Valco, Supro, and I think maybe even Dan-Electro. He’s near Richmond or Columbus Indiana. But, it is very likely your amp isn’t far from a comparable Fender schematic. And usually if the amp patient strays very far from the Fender circuit, and you don’t have an original schematic, you’d prob wanna make changes toward the Fender circuit especially where you can see where it was previously altered.

 

[sbolt]

There’s an amp tech is south eastern Indiana that’s widely accepted as the “Valco Man”. Supposedly, he’s the authority on everything Valco, Supro, and I think maybe even Dan-Electro. He’s near Richmond or Columbus Indiana. But, it is very likely your amp isn’t far from a comparable Fender schematic. And usually if the amp patient strays very far from the Fender circuit, and you don’t have an original schematic, you’d prob wanna make changes toward the Fender circuit especially where you can see where it was previously altered.

Thanks for your help! I have already found a blog where someone had made some improvements to lead dress, grounding etc. (on an octal version)....so at least I have that to work with so far.

 

[sbolt]

double post

 

[Powdog]

There were only so many iterations of the early Oahu/Valco single ended lap steel amps. Try starting here.

 

[Powdog]

There’s an amp tech is south eastern Indiana that’s widely accepted as the “Valco Man”. Supposedly, he’s the authority on everything Valco, Supro, and I think maybe even Dan-Electro. He’s near Richmond or Columbus Indiana. But, it is very likely your amp isn’t far from a comparable Fender schematic. And usually if the amp patient strays very far from the Fender circuit, and you don’t have an original schematic, you’d prob wanna make changes toward the Fender circuit especially where you can see where it was previously altered.

Terry Dobbs.

 

[Peegoo]

@sbolt

It's the same circuit as the Valco 510-11.

https://el34world.com/charts/Schematics/files/Valco/Valco_510_11.jpg

https://el34world.com/charts/Schematics/files/Valco/Valco_510_11.pdf

 

[sbolt]

There were only so many iterations of the early Oahu/Valco single ended lap steel amps. Try starting here.
View attachment 1390951

OK!!! it's the cap values that I am looking for thanks!

 

[Powdog]

@sbolt

It's the same circuit as the Valco 510-11.

https://el34world.com/charts/Schematics/files/Valco/Valco_510_11.jpg

https://el34world.com/charts/Schematics/files/Valco/Valco_510_11.pdf

Which is also the same circuit as a Spectator, the inspiration for the Spooktator!

Just transpose a 12AX7 for the 6SL7 dual triode.

 

[Peegoo]

@Powdog

Is that anything like ImiTaters?