Mystery Guitar Amp
I was given this little amp a long time ago. It has no markings or brand identification of any kind. Apart from changing the fuseholder and reforming the filter caps, this amp didn't need anything major done to it.
A little sleuthing revealed that it was manufactured by Valco, probably in late 1963 or early 1964.Online sources date the serial numbers G100–G5000 to 1962, but this amp seems to have been built later than that.
Everything about this amp looks like a Supro Super, but the examples I've seen online have different handles, have logos on the front, and have names over the input jacks.
The EIA date code on this pot says it was made during the 25th week of 1963 by Chicago Telephone Supply (137).
The EIA code on the speaker indicates that was manufactured by Jensen (220) during the
51st week of 1963.
The output transformer was manufactured by Triwec Transformer (524) on the 45th week of 1963.
The power transformer was also made by Triwec, during the 44th week of 1963.
The circuit is simple: a 5Y3 rectifier tube, a 12AX7 tube for preamp, and a 6V6G for output. Overall power is 5 about watts.
The venerable 6V6 power tube.