Without regulation, this basic circuit has the output current, and voltage determined by the transformer. The input can be 110 V and 220 V if the transformer used is of the indicated type.
This simple transistorized radio for listening on a crystal phone was found in a Japanese...
This very high voltage generator (VHV) uses a 555 and a power transistor with a heat sink. The...
Found in a 1969 documentation, this circuit is reset by a push button. The activation time is 100...