Keychain Car Alarm «Pandora» quickly puts the battery. When the battery voltage is less than half, then stick periodically shuts down when trying to open the car or the filing of any other signal. You have to turn it on and retry. And not the fact that he goes off again and not have to run around in search of batteries.
Why stick off?
The sudden shutdown caused by voltage drops in the transmission signal. Not exactly a new battery is unable to maintain the required minimum voltage level when the relatively powerful element keychain - transceiver module. This problem has been eliminated, including parallel battery electrolytic capacitor. In my case the battery at 1.5 volts, so the voltage on the capacitor took 6.3V, for less is not found, and in capacity - the more - the better, if only got into the space inside the stick. I was able to find on 1200mkF capacitor which got.
Installing capacitor Keychain
Take out the battery, unscrew the small screw (it is visible in the photo below).
Further disclose key chain.
In the picture above we can see the inside transmitter. Disconnect the receiver-transmitter module remote control (this is a small board with the upper antenna). Keychain without communication module in the photo below.
Now select the location of the capacitor. Here it is obvious, and it's as if the creators have thought (I have a capacitor is already in place for later took the photograph). Further positive to positive, negative to negative, soldered capacitor. The photo shows the connection of one leg to the positive electrode of the capacitor and soldered to the negative leg of the posting, going to the "minus" power. The capacitor just in case insulated shrink tubing. But is simply our "energy tank" does not fit, I had to remove some plastic dividers front trinket out of the place where now the condenser. Suffer from it is not, stick does not fall apart and generally in any way on the strength of it on the tongue.
It now remains to collect: put in place a driven unit (the result can be seen in one picture above), laid the wires so that nothing in the assembly do not interfere, we dress up the top cover, twist, install the battery, turn on the charm and rejoice. True, the more likely that one day, when keychain passed out while trying to pass a command to the vehicle, if it turns on, it just passed out in the second and subsequent attempts to transfer.
Energy batteries
I decided to swap out the extra customers in the key fob. Backlight - unnecessary, leaving the sound - can also be useful, leave it, the vibration - an extra thing, that is what we are on and off. Unsolder postings from motors, collected charm, turn - not working vibration, that slavnenko, but that's no team recognized the machine does not transmit it. Parse keychain vibromotorchik connect to the place - and lo! Everything works as before. Overall energy savings in the form of extra off consumers could not be implemented. It turns the motor winding is also used as inductance transceiver module, not a gift vibration motor on the board soldered APM.
And a couple of the modified transmitter inside: