Help Identify this Preamp?

[jrhussey]

Greetings:

Can anyone help me identify this preamp? Looks like a kit of some sort. It came to me through an estate. Uses 2 EF86 pentodes, a Sylvania 5V4 rectifier, and a Hammond 270CAX transformer.

Any help (user manual or schematic) will be appreciated.

Many thanks
Jim

 

[Paul Birkeland]

There is unlikely to be a schematic for this. It looks likely to be a triode strapped EF86, which has a high internal impedance of around 16K, which ends up being the output impedance of something like this, so it's not super useful as a preamp and wouldn't have been a circuit anyone would have been excited to publish.

On the good side, you have a chassis and a power supply you could use to make something different if you wanted to!