This circuit allows you to read capacitances on a common analog instrument. It is part of an article in the April 1990 Radio Electronics magazine.
This circuit was found in an 80's Electronic Engineering. The circuit uses a multivibrator with...
Figure bellow shows how many 40293 can be cascaded. The input CI of the first circuit is grounded. The...
This circuit is from Motorola documentation, but can be implemented with virtually any...