Radio Frequency Radiation Detector;

[KC4RAF]

This circuit DOES NOT intercept the transmission to where you can hear it!!!



Found an interesting circuit for detecting if cell phone is actually transmitting a signal. It's very basic design and cheap to build.
Here is the video at youtube on it:

https://www.youtube.com/watch?v=xgIL81VSKX4

That just shows that it works with the LED and a volt meter.


The next link is for that actual circuit build, just scroll down a little ways and you'll see it:

RF Radiation Detector | Rookie Electronics | Electronics & Robotics Projects

Surprisingly it works at detecting a transmission.
The circuit DOES NOT intercept the transmission where you can hear it! Only detect the radiation.

 

[CapStar362]

so its essentially a RF Detector?

looking for EMF Fields near radios

 

[KC4RAF]

Yeah, that's all it is. I thought for the simplicity

of the circuit, it might interest a hobbyist to try it out and gain some experience soldering, id caps, diodes and what not.

 

[cmdrwill]

That circuit was used way back as a RF field strength meter. Uses a uA meter in place of the LED.