This circuit is from the 1992 Radio Electronics Handbook. The components used are from the period, with emphasis on the 2-digit display driver.
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...