How can we design a cellphone detector similar to the one shown in the YouTube video, provided we set the following restrictions:
- purely passive, (no external sources like battery)
- power should come from RF signals from the cellphone
Notice that the brightness of the LED must be high. What components/diodes will we need and is there any schematics you could point out?
PS: based from the comments, they use RF diodes but didn't indicate any part numbers. Also, somebody tried it using RF diode/microwave diode but they failed to make the LED light up as brightly as in the posted video.