make some use out of the useless scroll lock!
a tale about how I hacked a mint keyboard backlight when I was supposed to study.
My dad brought me the Microsoft/Razer Reclusa keyboard earlier today. I did not ask for it, but I did like the idea of upgrading my ~10 years old keyboard.
It turned out to be a nice keyboard. I wouldn’t say it’s really a “gamer” keyboard ( unlike the wolfclaw etc ), but it’s got a nice feel to it, and that’s what matters to me.
While trying it out, I found the backlight to be quite annoying in daylight, even a bit straining the eye. I quickly installed the keyboard’s software and looked around for a way to turn it off. Failing to find one, I googled around, and the results indicated that the backlight cannot be turned off.
The keyboard is brand new, so it was a bit hard for me to decide, but I knew what had to be done. I had to pry it open and install a backlight switch!
I later decided it would be much more elegant to hook a transistor to the Scroll Lock LED to do the switching, rather than having an external mechanical switch. I knew it was generally possibly, but was not sure about the wiring.
This review was very helpful when taking the keyboard apart. I found it after I had already unscrewed all the bottom screwes except the hidden one, so it had saved me from possibly breaking the bottom plate. It had also served in guiding me to the LEDs.
This page served as a guideline for creating the switch. At first I tried the second diagram, using an NPN transistor ( I never use a PNP before, even though I had a few ). I hooked the Base lead of the NPN transistor to the + end of the LED, and the Emitter and Collector as shown in the diagram. When I connected the keyboard, I immediatly realised that I did a mistake.
The LEDs in the keyboard ( and if I’m not mistaken, generally in electrical circuits ) are toggled by their ground pin, the +V is always positive. I then realised I had to use a PNP transistor as shown in the first switch diagram.
It is important to note that if you don’t push the transistor to its saturated state ( if I understand correctly ) , the output will be lower that it should. I skipped the extra resistor because I can barely solder and I was too lazy to calculate or measure ( lost my multimeter ) the required values. I really don’t care about how bright the backlight shines anyway…
My soldering skills are horrible, and most of the time I relied on sheer luck. Here are some action shots:
Now I can turn the backlight on and off whenever I want!
PLEASE NOTE that the information above can and will cause damage to you and your surrounding. you have a high chance of breaking your keyboard and/or PC, and setting your house on fire. I am not responsible if you’re stupid enough to try it with as little background knowledge as I have.
However, if you do make this mod to your keyboard, please let me know!
The next step is to create a Gmail notifier that will flash the keyboard whenever new mail arrives =)