Intro: Mod Your Trust Multimedia Keyboard
When i bought this keyboard for my media center i saw that wasn't any power button, you just put batteries inside and you are ready to use the keyboard.
Unfortunately if you don't use your keyboard for some time your battery discharge rapidly.
So i decided to insert a power switch and a LED indicator to save battery life.
What you need:
- soldering iron
- electric cable
- little electric switch
- LED (i used 3mm diameter)
- 470 ohm resistance (depending of the type of LED used)
Step 1: Removing Screws
Turn your keyboard backside, remove batteries and find all the screws.
Remove them and remember their position (the screws are not all equals)
Step 2: Open Keyboard
Use a little screwdriver or a knife and find a good place where begin lift up the cover.
Remove the cover and rotate carefully the main keyboard (pay attention at the bus connecting the keyboard to the PCB).
You are now able to see a wire connecting the positive pole to the board.
Now it's time to decide where to drill the holes for the switch and the LED. I drill over the trackball because there was enough space and it is a good position to use with your inch.
Step 3: Switch and LED Circuit
If you just want to add the switch all you need to do is bypassing the wire.
Cut it in a place where you can strip it back easily and connect the switch using 2 pieces of cable.
If you want to add also the LED you need to connect the anode at the positive cable, after the interruption made for connecting the switch, the cathode must be connected to the negative pole of batteries, but in series with the LED you have to insert a 470 ohm resistance. (look the sketch below).
I soldered the resistance directly on one leg of my LED.
Note: 470 ohm is good for a normal green LED but it is not so different if you use another color. By the way you can find information about current of your LED and change the resistance by yourself.
Step 4: Complete Your Mod
Close the top cover carefully and put your screws back.
You have successfully modded your keyboard.