This TTL counter was found in the March 1991 issue of Radio Electronics magazine. The circuit is part of a larger project and must be powered by a 5V voltage.
With a strong positive feedback (via a 10 M resistor) we can get the trigger setting for the...
The critical component of this circuit is the transformar. We found it in an 1980s documentation....
This old oscillator using germanium transistors has a high impedance headphone as inductor to...