This is the receiver for the previous circuit, also found in 90s Radio Electronics. The circuit operates at 2.25 MHz, detecting variations in signal frequency due to the Doppler effect.
We found this circuit in the April 1975 Radio Electronics magazine. The circuit has a latch and...
We found this sophisticated home alarm in a 1994 documentation. The circuit supports sensors of...
This circuit was found in the 1991 Electronics Experimenter's Handbook. It activates a relay when...