This is the receiver from the previous alarm system. The circuit is from Radio Electronics, April 1989, and has an LDR as the sensor. Optical devices should be used to improve performance.
In this circuit the capacitor under test is charged at switch position A and then discharged...
Found in a Motorola manual from the 1980s, this circuit uses components from the era. The circuit...
This high-gain amplifier was found in the March 1994 issue of Electronics Now magazine. The...