42 kHz oscillator (CB21805E)

This circuit was used as an eraser for old tape recorders. The circuit is from a 1960 Mullard transistor manual.

SCR Passage Alarm (CB13378E)
We found this circuit in an old documentation from the 70s. The sensor is an LDR that must be...
2 meters preamplifier (CB20274E)
This circuit with junction field effect transistors was found in documentation from the 1980s. The...
1.2 to 1.4 V Power-Supply (NI025E)
Common general purpose silicon diodes when direct biased provide a voltage fall of about 0.6 to...