This 1974 circuit uses two 555 integrated circuits in a very traditional configuration. The circuit can be powered by voltages from 9 to 12 V and for greater volume an amplifier stage can be added.
Based on NXP 74HC logic, this circuit can be adapted for various uses. The circuit can also be...
This mixer or audio mixer uses common FETs that can be the BF245 or MPF102 and an operational...
This circuit is from a Motorola integrated circuit manual. The integrated used is no longer common...