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geekhack Community => Keyboards => Topic started by: Keycap on Tue, 14 February 2017, 16:34:36
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My Dell AT101W has a very faint Num Lock light, dim enough to make it hard to distinguish whether or not it's on in certain cases. I've also noticed that the keyboard sometimes just stops working out of nowhere. It starts working again if you restart the PC, but still, it's quite annoying. It has been like this ever since I got it.
This is what it looks like:
[attach=1]
[attach=2]
What I'd like to know is if the random shutting down has anything to do with the dim LED, and how to fix this. It has only ever failed on me three times, but that's enough to make me question why it's happening in the first place. What's also weird is that the LEDs are all at different levels of brightness. The Scroll Lock LED is brighter than the Caps Lock LED, and the Caps Lock LED is much brighter than the Num Lock LED. Seems to me like the keyboard is having a hard time getting enough power, maybe a blown capacitor is what's causing this?
All help is appreciated, thanks :)
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Time for an internal examination, with pics of course. :p :o
I'm not familiar with the AT101, so could be as you say, some bad caps.
Could be other possibilities like the current limited resistors going out of tolerance, the leds themselves, or if they are multiplexed and the NumLock isn't being held on long enough.
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I had an old keyboard with one dim LED. The only problem was that the leads of that LED were bent slightly so that one wasn't shining directly through the window.
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I had an old keyboard with one dim LED. The only problem was that the leads of that LED were bent slightly so that one wasn't shining directly through the window.
Yes, that's what I'm betting on, too. Why it fails from time to time, no idea.
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Any of the caps look like they're leaking?
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I had an old keyboard with one dim LED. The only problem was that the leads of that LED were bent slightly so that one wasn't shining directly through the window.
Yes, that's what I'm betting on, too. Why it fails from time to time, no idea.
The LED's on those boards are little rectangular shaped ones that can easily be bent out of alignment. On the inside of the case, the window has a surround that the rectangular LED is supposed to slide up into. If they are out by just a little when putting the top case back on the LED won't slide back into the surround but rather will slide to either the top or the bottom and not shine directly out of the little window making it look dim.
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Sorry about the long reply, I've been doing other things lately. I've come to the conclusion that it's definitely not a bent LED, as it looks dim even without the casing. Tried bending it but it's still dim.
In light:
[attach=1]
In dark:
[attach=2]
At this point, I'm guessing it is a faulty capacitor. Time to get the multimeter out!