Suggested by a 1990 book for amateurs, this circuit makes use of an integrated component that is not common today. It converts signals from one band to signals in a 10.7 MHz band below.
This stage circuitry for amplifying microphone signals makes use of germanium transistors as indicated...
This circuit was suggested by Philips in 1967 documentation. The circuit receives modulated light and has...
This circuit is from an English magazine of 1974, but can still be assembled with the replacement of...