This circuit is from an old Japanese publication of 1962. The circuit uses two batteries, one for the filaments of the tubes and the other one of high voltage for the plate circuits.
This circuit was obtained from a 1994 publication. Its purpose is to digitally switch 5 audio...
This circuit is the equivalent of the CB121, but is triggered with the negative transition of the...
This tuned circuit was found in a 1966 Electronic Circuit Handbook. The transistor can be any...