The circuit presented is a Japanese commercial radio for AM with 50 mW of output power, powered by 9 V. The circuit is from the 60s, having been found in documentation of the time.
This low power circuit for the FM band was found in a spy book from the 90s. The tunnel diode is...
This 3-decade operating range VCO was found in a 90s Popular Electronics. The circuit uses...
This circuit was found in an Electronic Design from the 90s. Operational amplifiers admit modern...