This timer was found in Japanese documentation from the 1960s. The transistor can be replaced by an equivalent and the relay must be of the sensitive type with voltage according to the power supply.
The frequency of this circuit is determined by the 100 uF capacitors. These components can be...
This crystal-controlled 1000 kHz oscillator was found in 1980s American documentation. The...
This circuit was obtained from an American documentation from 1976. The circuit has a dynamic...