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.
Passaje Alarm This locking circuit was found in a 1988 publication. It locks a relay when the...
Found in a publication for radio amateurs from the 1980s, this circuit amplifies signals in the 60...
We found this circuit in an application note from Linear Technology of the 90s. The circuit uses...