This circuit was found in a Philips documentation from 1970. The components are of the time, difficult to find today, but the configuration can be adapted to use modern equivalent components.
This circuit is based on a Texas Instruments LinMOS integrated circuit consisting of an...
This sophisticated logic probe for 5 to 12 V circuits (CMOS and TTL) was found in a 1980s...
This 2005 Linear Technology circuit has separate outputs for monitoring the charge and discharge...