Mystery amp

[TC Chris]

Not quite sure where to put this, but since it came from a record player, I'll try here. The thunderstorms that were forecasted and shown crossing Lake Michigan on the radar never showed up, but I stayed home and farted around just in case.

This is a little P-P 6V6 amp from an institutional record player, the kind I remember from grade school in the gym: a black case with a speaker in the removable lid. The amp was given to me and has no identifying info. Tubes are 6SC7, 6SN7, two 6V6, and a 5Y3 rectifier. The caps are Sprague oil caps--serious components. It has input level controls for mic and phono and a tone control.

Long ago I made a very makeshift case for it so my brother's buddy could use it for his lap steel.

Here are pics.

Any idea what this is?

Chris Campbell

[William]

Nope, but there sure are a lot of taps on the PT and the PT has holes in it.

Bill

[TC Chris]

Nope, but there sure are a lot of taps on the PT and the PT has holes in it.

The little amp just says "heavy duty" with those fancy Sprague oil caps. And as for the taps, 2 would be 5V for the rectifier heater, two would be 6.3 V for the other tubes, and 3 would be the CT B+ winding, so there's 7. And I see a jumper across 2 of the taps, so that's 8. Two extras!

Wish I knew what this was so could search for a schematic.

Chris Campbell

[TC Chris]

I was poking around online, trying to find commercial/institutional phonos from the 1940s. Not much luck. I tried Newcomb and Califone but everything I found for them was 1960s-70s. Who else made phonographs in the 40s in commercial grade? Maybe Stromberg-Carlson?

Chris Campbell

[electra225]

How about Bogen or Webster Chicago.....

[Hi-Fi-Mogul]

What are the date codes on the transformers ?

That would help settle the time period question,
and assist in searching.

The below Newcomb unit is getting closer to your tube lineup.

https://www.radiomuseum.org/r/newcomb_p ... known.html

[Firedome]

Also perhaps Masco, Rauland, other small fry?
I'd guess late '40s to mid '50s, for school, commercial use, given the cap and trans quality.

[TC Chris]

I'll try a search on the new names. Unfortunately, I put the device back in its enclosure and the enclosure back on the remote end of its shelf before recording any component codes. I did write down some part nos.for the fancy Sprague caps.

Chris Campbell

[Firedome]

Interestingly the old Sprague factory in Pittsfield Mass is now Mass MOCA: the Massachusetts Museum of Contemporary Art, an excellent museum.

[hermitcrab]

Are the tubes dated ?... even though they might have been changed in the past it would get you close to the time period

[Conelrad]

Neat lil amp.

Nothing newer than octals in my stuff.

Conelrad

[TC Chris]

The caps are mil-spec. Scroll down to p. 38 of 56 and check out the CP26 caps. These are CP26A1E.

https://www.technicalaudio.com/pdf/Elec ... EM_E30.pdf

Chris Campbell