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 amplifier is from the 80s integrated circuit manual itself. Equivalent configurations can be adopted for...
Other operational amplifiers series, such as the MC34072, MC34074, MC35071, MC35072, MC35074 d...
This circuit was published in a 90s Radio Electronics. The circuit uses the well-known LM386 that...