mobile phone led flashing stickers !

[dilan2005]

hi,
as it seems those flashing stickers flashes when there is a signal tx from the phone.
is any one know how these flashing stickers work!(i mean the actual cirucit insde these stickers). it seems there is more than a inductor and a led.

Thanks you

rgds
dilan

 

[pranam77]

Hai Dear,
It will have an detector coil connected to an IC which is basically a UHF frequency detector and a integrated flasher which will drive the tiny led's. The required voltage is fetched from the transmission Antenna of the mobile handset and the coil supplies the same to the chip. thus coil does dual function. An antenna and the voltage source to the circuit. You too can build a similar circuit with through hole devices. A easy to assemble kit is available at www.united77.projects.htm.
Goodluck.
Pranam77