This circuit is from a Radio Electronics magazine from February 1992. The circuit has the effect speed dependent on C1 and adjusted by R3.
This fully isolated control circuit provides an output signal by triggering a 130 mA relay when...
The capacitor used in this circuit can have values between 5 and 30 uF. The circuit is of old...
We found this circuit in an old Argentine publication. The transistor can be replaced by a more...