This simple latching alarm circuit using CMOS gates was found in the May 1990 Radio Electronics magazine. The supply voltage is dependent on the relay.
This loop antenna was found in a 1990s documentation. The circuit includes a field strength meter. The...
This power supply is protected from shorts in the load. The BD135 must be mounted on a heatsink...
By the components used this circuit of old English documentation can still be easily assembled. The...