Originally designed for WWV (Standard Time Station) signals, it lets 1 kHz tones pass by rejecting the 440 and 600 Hz tones emitted by the station. The circuit is from a 1964 Electronic Design.
The circuit shown in the figure is suggested by Intersil (www.intersil.com) and makes use of the...
We found this version of the automotive tachometer in a 1980s publication. Variations from other...
The battery charger shown in the figure uses two 60 W incandescent bulbs in series to limit the...