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.
I found this circuit in an article in a 2003 publication. The circuit is an example of how to...
This circuit drives a buzzer or electric buzzer but can be used to trigger a relay or other load....
May 2017 - Mouser Electronics is already in stock with the new BCP1395 transistors from Nexperia....