The figure shows the equivalent circuit for the LM381 audio preamplifier IC. The circuit was found in the February 1990 issue of Radio Electronics magazine.
This silencer or squelch preamp circuit was found in a documentation for radio amateurs. It...
This circuit was found in a 1994 publication. It draws 1 of 41 LEDs when we press and then release...
This circuit makes use of a diac to stop the activation of a sensitive reed relay 1 mA. The trip...