This circuit was found in an Elektor from the 90s. Next to the circuit we have a table with the delays obtained when the circuit is connected according to the positions of the selector switches.
This circuit was found in an English magazine from 1983, but it can be assembled with BC548. The...
This circuit was obtained from a 1965 magazine, but can still be assembled if we use a modern 6 V...
The frequency of this oscillator can be set in a range from 5000 to 1. We found it in an old...