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:

- screwdriver
- scissors
- drill
- soldering iron
- electric cable
- little electric switch
- LED (i used 3mm diameter)
- 470 ohm resistance (depending of the type of LED used)

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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.

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    8 Discussions


    9 years ago on Introduction

    Does the battery discharges rapidly?I think there would be little current when you don't tap the keys...Just guess,no experience...
    May be you can measure the current by  a ammeter,and if it is below 10uA,there is absolutely no need to insert this switch.
    If your battery is 800mAh,with 10uA current ,there will be 80000 hours for the battery to be totally discharged.80000/24=3333days=~10 years.
    Even if the current would up to 100uA,there will still be about 1 year.
    And maybe that is why the manufacturer didn't add a switch.

    In my opinion,don't turn the switch rapidly.Because there will be a peak current the time it turns on.And it is a waste of power rather than saving.

    1 reply

    Reply 9 years ago on Introduction

     Well, your theory is not wrong but i don't use this keyboard so frequently and the first time i leave it for  some weeks i notice the discharge problem. From that time i began to pull out one battery each time until i decided to make the mod.
    I don't know if there is a peak current or not when i turn it on, but now my keyboard is working from months with the same batteries.


    9 years ago on Introduction

     Nice, but you really should have used a smaller switch, and positioned it out the back.

    1 reply

    Reply 9 years ago on Introduction

     I used that type of switch because i don't like flat switches and i havn't other at home. By the way in my opinion that position rules becouse i personally turn my keyboard on and off continuosly, not only when i start using it.


    9 years ago on Introduction

    I wonder why the manufacturers don't just add a switch on the back. And not a standby switch, a real off switch.

    Well done mod. Well done indeed :).

    1 reply

    Reply 9 years ago on Introduction

    Strange, as Trust did add an on/off switch in the model that I have.
    My keyboard is almost identical to laurentio's, but it has a button just below the mouse ball for said purpose.

    Still, it is odd why they would release this keyboard in the first place...


    9 years ago on Introduction

    Cool, you should make a mod that uses internal rechargeable batteries.


    9 years ago on Introduction

    Very nice!  Well written, with good warnings about what to watch for along the way.  Including the LED indicator is a nice touch.