This relay shield circuit for old computers was found in January 1983 Radio Electronics magazine. The relays are sensitive types with currents up to 200 mA.
This circuit activates a relay after a time given by C1 and R1. The circuit is from a Radio...
This circuit can be used as a control shield for microcontrollers of all types. The supply is made...
In this circuit, D.A. which is actually O. A. of an operational amplifier, which can be any type...