This circuit was obtained from an 80's Radio Electronics. The circuit decodes “scrambled” or sinusoidal encoded signals by providing an audio signal at the output.
A frequency range determined by the network of resistors and capacitors with negative feedback and input...
In the figure we have a low-pass filter, with a cutoff frequency of 10 kHz, also suggested by...
In the figure we have the way to use the comparator LM339 and others of the same series with the...