This circuit is from an old American documentation using as indicators for the flip-flops neon lamps. This way, the circuit has two supply voltages.
This circuit was obtained in a 1985s English magazine. The circuit can still be assembled with...
This circuit was found in a 90s American documentation. The circuit uses an LED that can be of a...
The circuit presented is from the National Semiconductor's Linear Applications Handbook of 1994. We...