This conventional 4 channel circuit with the 4017 and 555 was found in the November 1991 Radio Electronics magazine. The potentiometer can be 47k and it controls the speed of the effect.
We found this configuration in a 70s American documentation. The circuit makes use of operational...
The circuit shown is powered by 5 V and was suggested by Motorola's Linear Databook of 1990....
This simple transistorized intercom circuit was found in a 2000 documentation. It can be powered by a...