We have many tube tester circuits in this section. This one came out on a Radio Electronics from 1949 and has a very elaborate configuration with toggle switches.
This circuit is from a 1968 Electronic Design. The components are from the era and the operating...
This circuit was found in an Electronic Design from the 90s. The integrated circuit is from that...
This circuit, from a 1988 documentation, activates a relay for a period and has a touch shutdown as...