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.
This circuit was originally used in a 1989 documentation presence simulator. The circuit activates...
This old circuit uses an operational one from the 70s, but it is still useful in current projects. The...
We found this circuit in a Popular Electronics from the 80s. The circuit is based on the LM3909, a low...