The figure shows a remote-control receiver working the 27 MHz band, very popular in the 60’s. The circuit us from a February 1961 Radio Electronics magazine.
This is an amplifier with one of the first integrated circuits available, the CA3020 which was...
This circuit was obtained in a 1964 Electronic Design. The transistors are from the era and the...
This low power circuit for the FM band was found in a spy book from the 90s. The tunnel diode is...