This circuit also detects IR, providing LED indication. The circuit is used to indicate humidity in bench tests. We found it in the Radio Electronics magazine of February 1990.
This is a circuit published in the January 1962 Radio Electronics magazine. The circuit is for...
This diagram was found in the November 1972 issue of Radio Electronics magazine in an article...
This circuit with the CK722 was found in a Raytheon publication from the 60's. The relay is of the...