[Dept. of Computer Science]

Isolation Transformer plus DC Supply

Our Department and University.
See my other radios too! (Here is the next one.)

For work on transformerless radios an isolating transformer is recommended to supply the set with a line voltage that is isolated from the ground. This unit functions as such an isolating transformer, and also has the possibility to output 110V of AC for work on American radios.

The unit was produced from scrap computer parts. I took two power supply transformers, both with 28V of output, and use the second one to transform the output of the first back to line voltage. Its primary coils can be switched between parallel and serial for either 110V or 220V of output. In its previous life, the plastc cabinet housed a 68000-based whatteverriddas.

With some old semiconductor scrap I added a DC regulated power supply that can be controlled from 5 to 10V DC. In this way the unit also supplies transistorradios without the need to search the house for suitable batteries.

Gerard Tel, gerard@cs.uu.nl.