Found in RCA documentation from the 1960s, this 60 V regulator has a 100 V input and a current of 1 A. The transistors are from that time. One can try to use modern equivalents.
This circuit was found in the March 1994 issue of Electronics Now magazine. The circuit uses a...
This receiver for an audio link by modulated light was found in a 90s Elektor. Transistors are common...
This circuit was found in a 73 magazine for radio amateurs from the 90s. The circuit uses high...