This circuit was found in documentation from the 1970s. However, it can be implemented with modern transistors such as 2N2222 for Q1 and BF494 for Q2. The crystal depends on the desired frequency.
An oscillator whose frequency can be adjusted between 500 Hz and 5 kHz with the use of a...
This circuit of industrial applications has an interesting characteristic: the relay is only...
Any TTL inverter can be used in this circuit. We found it in documentation from the 80s, but it...