We found this circuit in the Radio Electronics magazine of December 1972. It generates signals in 6 frequency bands, being indicated for experimental applications with TTL circuits.
We have in the figure a traditional amplifier configuration with operational amplifier. The source...
This circuit was found in a 1977 Radio Shack documentation. The circuit is TTL, which must be...
This circuit is suitable for modulating small FM transmitters for eavesdropping or espionage. The...