This circuit was found in the November 1966 issue of Electronics Now magazine. It uses an LDR as a sensor and has a Bargraph scale with the well-known LM3914.
This circuit was found in an American publication from the 1980s. In the original version it...
This circuit is from an American documentation of the 1980s. The circuit can be implemented with more...
This is a diagram of a 1958 commercial receiver. The circuit was found in documentation at the...