This CMOS integrated alarm was found in the July 1992 Radio Electronics magazine. The circuit has a small power stage and its sensitivity is adjusted at R5.
Suggested by Siliconix in documentation from the 90s, this amplifier has its gain digitally...
This circuit is from Radio Electronics. The magazine no more exists, but the circuit can be...
An oscillator that uses two gates is not suitable for critical applications, as it tends to pick...