We found this circuit for musical instruments in the March 1992 Radio Electronics magazine. The circuit has outputs according to the desired scale from a crystal oscillator at the indicated frequency.
We found this circuit in a 1987 Hands On Electronics. It was indicated at the time to power...
This amplifier, suggested by National Semiconductor (Now Texas Instruments), has high input...
This circuit causes one LED to light up if the voltage falls below the value set in R3 and the...