DIY Batteryless SmartTag

I'm sure many people already done this.

But here is how I did it.

Prepare the parts :- a 9V IC regulator. ***7809, 2 pcs of 100uF/16V e.capacitors, and a heatsink and pcb.


Then solder all the parts together. The IC pin when seen from front side is Input-Ground-Output. Connect the E.cap at input to ground and output to ground respectively.


Buy the ciggarete jack (since im not smoking, better put it to good use) and open it up and rig a switch to turn it on and off.


Solder the input and output to the regulator. Need to cut the battery connector inside the battery compartment of the smarttag.


On the battery cover of smart tag, u will notice a small notch. Cut it
out for the wire to go out.


Finally cover it up nicely. Done!


And you will never need a battery ever again. Huhu...

Next DIY is to put a LED lighting to the SmartTag LCD screen.. hehe..

thx blackhowling.. (or orangehowling?)..
ciggie no power means ur fuse blown maybe..
or ur battery kong hahah...

true millenium. its individual preference. if u like wireless (as my wife would prefer too), then, use battery lor...

me, i dont like to use battery. sue me, im cheapskate hahah...

sentraVIP, the schematic is simple really.. and those part u can buy from pasar road.

the IC is a normal 1Ampere regulator (although u dont need 1A type, u can use lower Amp type.. like 150mA ones).. part number is in the form of ***7809*** 7809 means positive output 9V. similarly, 7805 is positive 5V output.

schematic as attached.

sentraVIP, thats a good idea too. in a way, it camouflaging the tag as something else (deterrent for thieves).. i really hoping that the tag was built a lot smaller so, it will fit in a women's handbag.. but now the size is bulky.

if u think of taking it apart, do take care about ESD (electrostatic discharge) from your body. Strap yourself to earth by wire to avoid damaging any sensitive parts inside (esp ICs or transmitters)..

i tested my batteryless smartag when driving to kampung.. all is AOK. however i realized a few disadvantages.

1. if there are no smartag lane, i need to take out the card from the tag (since the wire i used is a bit shorrt - just enough to place the tag on the dash.).. but for me i think thats ok. (not that hard to take out the card right?).

2.if for some reason, the tag did not read thru at a smartag lane, normally the toll operator will come and ask for the tag. haha.. if u diy this, it will be impossible to give it. (but can always just give her the TnG card.... ;P)

so those who want to DIY theirs, might want to take these 2 points in mind when designing the connection.