This tone recognizer circuit that relies on R5 and C1 was found in the December 1994 issue of Electronics Now. The circuit operates on voltages from 6 to 12 V typically.
This high-gain digital amplifier uses general-purpose transistors. The supply voltage is logic...
The output voltage is adjusted by the trimpot. The power transistor mist be mounted on a heatsink. The 3.9...
Data applied to the input of this circuit is shifted one ceII to right following the clock pulse....