This circuit was found in the January 1995 Electronics Now magazine. The source must be dual, and a noise pickup guard ring must be used.
What is a dual frequency generator for? There are several possibilities of use for this circuit. The...
The circuit, illustrated in the figure, consists of the direct application of the ULN2003 in which...
This circuit was found in a Popular Electronics from the 90's. The output signal can be applied to a...