This circuit for low frequency data transmission was found in the May 1977 issue of Radio Electronics magazine. The circuit modulates the signal at two frequencies for bits 0 and 1.
This circuit for frequencies of 20 to 2 kHz was obtained in English documentation from 1966. The...
Indicated for adjustment in transmitters for the 11-meter band, this circuit with analog meter was...
The circuit shown uses the LM340 but applies to other regulators. We found this setting in...