This circuit was found in a 1968 documentation. It makes use of both NO and NC reed-switches and small magnets attached to a card in the form that results in the drive combination.
This is the receiver for the CB18476E, but it can be used with other transmitters found on the...
This circuit was found in Radio Electronics from the 90s. The CMOS integrated circuit is a PLL not...
This circuit was found in a 1990 Electronics World magazine. The circuit can be mounted today by...