This small tone generator was found in the November 1987 issue of Radio Electronics magazine. The phototransistor is common and controls the sounds generated. The basic frequency is given by C1.
This circuit is part of a sound system project published in the October 1970 issue of Radio...
This circuit is from the National Semiconductor Audio Handbook, as it uses an audio power...
May 2017 - The new 36V TLVx171 Series of General Purpose Operational Amplifiers from Texas...