Electromagnetic Flashing Stickers

[rahul986]

Nope. I tried that but in vain. The LED just didn't glow. I used 40 turns of coil around a 1cm diameter material. If anyone of you got it right can you post the circuit so that I can cross check with mine. Anyway before I get a reply, I'll try out the circuit in my college's electronics lab.

 

[Nigel Goodwin]

Nope. I tried that but in vain. The LED just didn't glow. I used 40 turns of coil around a 1cm diameter material. If anyone of you got it right can you post the circuit so that I can cross check with mine. Anyway before I get a reply, I'll try out the circuit in my college's electronics lab.

I would suspect you need the coil tuned to the output frequency of the phone, this is likely to be very little of a coil at all for the frequencies involved.

 

[Someone Electro]

I gues the iron core you used gave it to much inductance(The signal broke it self).You shod try whith air core and a flat coil.Or meaby 40 thurns is to much.As i sead eksperement. (Try difrent tipes of coil,difrent number of thurns,difrent wire...)

 

[rahul986]

Hmm. I'll try that. May be i'll need some time for that. Before that if anyone gets some other idea please post it

 

[grrr_arrghh]

there are quite a few 'mobile phone trackers' circuit diag around on the net, maybe that would give you some hints as to frequencies etc.

i seem to remember that a mobile phone signal (unless decoded) 'pulses' - maybe this would be some use in getting the LEDs to flash...

just my thoughts

Tim