This 50% active cycle TTL clock generates signals from 4 to 20 Hz. Its power must be supplied with 5 V and other frequencies can be generated with capacitor replacement.
We found this configuration in a 1974 technical documentation. It can test both TTL logic circuits and...
This circuit emits an alert sound (interval beeps) if the car lights are left on and the ignition key...
This is an amplifier that uses a pickup coil placed next to the telephone set and the listening is done in...