This is the transmitter for a remote-control system published in the August 1986 issue of Radio Electronics magazine. The circuit uses two 555 CMOS transistors to drive two series LEDs.
This circuit was obtained from an American 80's documentation. The balanced mixer can be shown in...
This circuit was found in a 90s Electronic Engineering. The quadruple operational amplifier can be...
I found this circuit in an English publication from 1989. This configuration can be mounted with...