This 3-valve receiver was found in a publication by Edelman from 1924. The circuit has two supply voltages, B being 60 to 90 V.
Found in 1980s documentation, this oscillator uses an integrated TTL Schottly. The supply must be...
This circuit was found in Electronics Today International of the 80's. The circuit uses still...
This circuit was found in an Elektor from the 90s. The circuit uses common components even today,...