General Transformer TRA-400-B Transformer 380-0-380 / 6.3 V Revere / Wollensak / 3M Vintage Power Tested Tube Amp Project 1950

Fully 60 Hz AC tested and guaranteed vintage tube preamp transformer. AC testing using an oscilloscope allows us to find and reject transformers with noisy or lossy outputs, which a simple resistance or continuity test will not reveal. Our testing also ensures that you have access to the wires and that they are bundled sensibly, eliminating the "discovery phase" (see below!). Made in USA in 1950 by General Transformer for Revere / Wollensak / 3M. IEA date code 412039. Weighs 3 lbs 4 oz. Bolt spacings 51 mm by 47 mm. Quantity sometimes available - please enquire.

This transformer originally provided B+ and heater supply for these tubes: 12AX7, 6SJ7, 6V6, 6X5

Here are the verified connections for this transformer:

Input: 117V

Outputs:
760 VAC center tapped
6.3 VAC

We use a standardized wire identification scheme featuring bright cable ties. In case of any ambiguity, 117V input will be wrapped with a black cable tie, red is high-voltage, yellow is 5V for rectifier, green is 6.3V, blue is 12.6V, white is 117V out for 220V input or tubes with series heaters, purple or grey is a second (or third!) 6.3V output. The voltages run a bit higher when run at modern AC levels instead of the 117 VAC that was specified in the 1950s and 1960s. Serial number T-1149.