We found this circuit in the August 1990 issue of Radio Electronics magazine. The two-digit circuit uses a pressure sensor and is powered by a 9V battery.
The purpose of this circuit is to 'produce a beam of infrared rays modulated at a frequency that...
The circuit shown is intended for cable testing, providing status indication via LEDs. The number of...
This '90s circuit found in National Semiconductor documentation uses components from the time. |...