This circuit was found in the December 1977 issue of Radio Electronics magazine. The 4-digit circuit is based on TTL logic and must be powered by a voltage of 5 V.
This circuit is from 2002 documentation. It injects a signal into a power amplifier and measures the...
The integrated circuit used in this project is not the most common. The use of a crystal...
This configuration was found in an American publication from the 90s. Operators admit equivalents just...