EMERGENCY-PORTABLE NOKIA CELL CHARGER
ABOUT THE CIRCUIT AND PROS
Smallest nokia charger, u can even charge you mobile while jogging or when u r stuck in a jungle. I made this circuit when i heard of IIT'ians charging their nokia cell phones with portable windmill. :-(
CONS
Its not an economical solution, 9v dry cell costs around Rs.18, rechargeable NiCd 9v costs around Rs.170. a single 9v dry cell can be used for only a little more than 1 charging cycle only (aprox.)
TESTING OF THIS CIRCUIT
Tested my charger circuit on nokia 6600, 1100, 2300
PICTURES
This is my cell along with the charger circuit. (up)
This is my cell charging from the charger circuit. (up)
HOW IT WORKS
The curuit is quite small n easy, needs no explanation. The 7806 steps down the 9v from battery to 6 v. I attached a small capacitor just because i love my phone( to pull down any spike if produced to pluad connection n disconnection.
COST
Nokia plug and wire= 15Rs Battery 9v= 18Rs 9v Battery lead= 5Rs 7806 IC= 8Rs Capacitor = 0.50Rs
TOTAL=50Rs aprox
TECHNICAL DETAILS
My nokia charger gives 5.7 volts when connected to mains. It gives 6.0 volts when connected via inverter or UPS. In this circuit i charge my cell with 6.0 volts. 7805 can not be used as Nokia cell does not charge below 5.7 volts ( there is also a limitation on the amount of current too). As soon as this circuit is connected the voltage across 9v battery comes out to be 5.5v instead of 9v. I connected my circuit to a transformer based 9v supply and it did charge my phone, however when i connected a 12v battery it showed "not charging". I got the same not charging warning when my (v battery got discharged and was not able to provide current large enough to charge my battery.
Warning - I am not responsible incase you blow up your cell phone with this circuit.