Using a sensor from the time, this circuit was found in the 1992 Radio Electronics Handbook magazine. The circuit uses a pair of integrated two-digit A/D converters.
A frequency divider for digital signals can be constructed based on a single 4018 integrated...
This transmitter emits a modulated signal at a frequency given by the first transistor in the...
The figure shows how to use an LM3914 with a variable range moving point. The circuit has an...