This constant current source for high voltage loads was obtained from a 1967 General Electric documentation. The components are of the time, but allow equivalents.
The transistor can be the BD135 and this circuit, found in a 1978 publication, can be powered by...
With this circuit it is possible to receive VHF stations up to 100 MHz on a common FM receiver tuned...
The transistors of this circuit can be BC548 for NPN and BD136 for PNP with load up to 500 mA. The...