This Nixie pipe circuit was found in 1965 documentation. Note the high supply voltage. Appropriate transistors of the time were used.
Using the name of varactor this circuit was found in the Radio Electronics magazine of July 1982....
We found this circuit in a 1960 Radioarama magazine. The instrument tests common general-purpose transistors...
This circuit uses an RCA module from the time. The circuit is from a Radio Electronics magazine from...