Found in a 1969s American documentation, this circuit uses transistors from that time. The configuration can be adapted to use modern equivalent components.
This circuit was found in a 1980s telecommunications publication. The circuit uses a diode bridge to...
This circuit is from an English magazine from 1980, but it can be easily assembled with more...
The indicated circuit is an intermittent one in which we use two 555 integrated ones, one as a low...