This circuit for multiple sound inputs was found in a Radio Electronics from January 1992. It consists of a Bargraph connected to a multi-input mixer.
This circuit was obtained from a European magazine of the 1990s. The integrated circuit used is...
Using a ceramic resonator, it is possible to vary the frequency between 4.9 MHz and 5 MHz. The...
In the figure we have the way to obtain a monostable action by lighting an LED for a certain time...