This FM advertising suppressor (SCA) decoder circuit was suggested by Signetics in a 1980s documentation. The circuitry decodes the 67 kHz signal. The integrated circuit used is of the time.
The CMOS 4046 integrated circuit is not very common today, consisting of a very efficient PLL for...
In the circuit shown in the figure to the side, the relay is activated when the light stops...
With this name, the English publication where we found this circuit indicated a sensitive touch...