GSM em-radiation detector LED thingy/bug - Page 1
Forum section: electronics / beginners

author: calli
author_rank: Regular Contributor
timestamp: December 04, 2017, 06:41:51 pm
content: Hi,just out of cuoriosity I bough such a "bug":https://www.ebay.de/itm/DIY-Kit-ICSK032A-Mobile-Phone-Signal-Flash-Light-Radiation-Power-New/272780461231Consists of 9 germanium diodes and a LED.It does not work. I THINK I put it together the right way. Yes I have a GSM Phone here bt not the faintest light in the LED even while making calls. The LED is working, the diodes are ok with diode tester.Could it be(e) that my changes for "cosmetic" reasons disturbes? I cut the LEDs legs and also the one diode in front is shorter "legged". The longer "antenneas" I don't know, tested all I could think of with the original ones.I also put my Oszi in place where the LED sits, but nothing but that was maybe stupid, I got interesting curves but nothing that changed with the cellphone or my desk lamps in the perimeter.Cheers,Carsten

author: Gyro
author_rank: Super Contributor
timestamp: December 04, 2017, 08:39:08 pm
content: Just for reference, those are Silicon diodes, not Germanium, probably 1N4148s.

author: calli
author_rank: Regular Contributor
timestamp: December 04, 2017, 09:17:05 pm
content: I measured a forward voltage of 0.21V, that was confusing me.I think it is this:http://pdf1.alldatasheet.com/datasheet-pdf/view/83373/HITACHI/1SS86.htmlAt least not pure Silicon :-)Carsten

author: Gyro
author_rank: Super Contributor
timestamp: December 04, 2017, 09:35:56 pm
content: Ah yes - high frequency Schottky looks very plausible. My mistake.Personally I'd ditch the detector and make use of the diodes.Note that they areveryESD sensitive... 30V!

author: MasterT
author_rank: Frequent Contributor
timestamp: December 04, 2017, 09:48:52 pm
content: Probably, it was designed to work on older network, GSM-900 (2G), if your phone ( and network operator - Service Provider) supports manual selection between 2G and 3G, than you can try to register on the 2G and make a call.

author: calli
author_rank: Regular Contributor
timestamp: December 07, 2017, 03:55:22 pm
content: I have a G2 mobile here. No lights.Carsten

author: jmelson
author_rank: Super Contributor
timestamp: December 07, 2017, 10:40:13 pm
content: Quote from: calli on December 07, 2017, 03:55:22 pmYeah, if a gadget like this ever lights up, throw a chair through the window and run for you life! The amount of EM radiation it would take to make it light up would indicate you are practically inside an operating microwave oven.Jon

author: calli
author_rank: Regular Contributor
timestamp: December 08, 2017, 08:18:15 am
content: I think it should work. I guess not all YT videos with theese devices can be fake and lately there was a art project with such devices. And some years ago you could hear the "tac-da-tac-da" of mobiles near a audio amp very often. Yes, G3/G4 is much more silent but therefore I tried with an old (still going) phone.Carsten

author: Kalvin
author_rank: Super Contributor
timestamp: December 08, 2017, 01:51:30 pm
content: I wonder why so many diodes. The LED is diode on its own, so it might work even without other diodes. However, if the LED has too much capacitance to work as a decent rectifier (after all, the GSM works around 1GHz - 2GHz), one could add another rectifier diode in series with the LED.