This approach alarm circuit was found in the September 1970 Radio Electronics issue. The 1 mH coil is wound on a ferrite rod. The relay is 12 V sensitive.
The circuit shown is from the GE semiconductor manual of 1977. In the table we have the values of the...
This 1967 Ferranti circuit uses company components. These transistors can be replaced by modern...
This 15 V regulator uses the integrated 100 mA L series. The circuit was suggested by Motorola's Linear...