This circuit was found in an American documentation from 1969. It serves to trigger circuits by providing a 7.5 V signal at the output from 500 mV pulses.
This simple electroscope with bipolar transistors is not the most sensitive, but can detect static...
This oscillator for various frequencies was obtained from a 1980s telecom documentation. The...
This circuit is from a July 1970 Radio Electronics magazine. The sensors are metal probes. The 18 V...