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geekhack Community => Keyboards => Topic started by: shawn o on Sat, 28 April 2012, 20:27:07

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: shawn o on Sat, 28 April 2012, 20:27:07

Keyboard currently has red LEDs and I'd like to swap em with clear ones that illuminate blue.

Has anyone done this? What spec LEDs should I be looking for?

Forward voltage in blue LEDs is typical higher than red so it shouldn't matter much really right?

LEDs might just be dimmer when caps lock or scroll lock is on (almost never) I think?

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: Squelos on Sat, 28 April 2012, 20:57:45

Yeah, the voltage wont change much. Just be sure not to fry your new led. Try checking specs if you cant. If you cant, reverse engineer, and add a resistor if necessary.

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: hazeluff on Sat, 28 April 2012, 21:31:44

Quote from: shawn o;585181

Keyboard currently has red LEDs and I'd like to swap em with clear ones that illuminate blue.

Has anyone done this? What spec LEDs should I be looking for?

Forward voltage in blue LEDs is typical higher than red so it shouldn't matter much really right?

LEDs might just be dimmer when caps lock or scroll lock is on (almost never) I think?

Its dependent on forward voltage and current. So, it could work, it could possibly not work.

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: shawn o on Sat, 28 April 2012, 21:39:50

Snap On multimeter in diode mode shows 1.81V for the red LEDs on the board now. Look like all the Digikey blue LEDs are 3.2v or greater. So keyboard will be ok, LEDs will just be dimmer when lit, right?

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: alaricljs on Sat, 28 April 2012, 23:24:12

I have used a lab supply on 3.2v leds to test for minimum voltage.  1.8 will not cut it for even a hard to see blue dot.

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: tp4tissue on Sun, 29 April 2012, 01:11:51

Quote from: shawn o;585235

Snap On multimeter in diode mode shows 1.81V for the red LEDs on the board now. Look like all the Digikey blue LEDs are 3.2v or greater. So keyboard will be ok, LEDs will just be dimmer when lit, right?

It depends on the LED, in most cases, if the voltage is below the rating, then it just won't jump the gap, little to no light.

You can build a circuit with a separate controller though, cost more, but you can do crazy things, like blinking, and  strobe, for keyboard disco mode,,

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: shawn o on Sun, 29 April 2012, 10:27:29

Ya, I saw that thread, thanks for making it. Why would it potentially damage the keyboard itself?

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: Squelos on Sun, 29 April 2012, 17:22:24

If the voltage is really too low, the diode wont even light.
But after that point, the lighting is progressive and linear.
1.8v for a 3.2 does seem low. You might need to bring in some more power using transistors for instance

Edit : i am talking about them really bright leds. Not the ones that just indicate ON/Off for instance. Cant really remember, but I think you are going to have to get the full voltage, otherwise they wont light up at all, or will be barely noticeable.

Title: Swapped LEDs on Filco Tenkeyless Cherry Black
Post by: shawn o on Sun, 29 April 2012, 20:37:04

Soldered in some blue 3mm NTE Inc. LEDs and they work perfectly and seem to be nearly as bright at my Filco with browns (and blue LEDs).

Part number is NTE30036 for anyone that cares.

http://www.nteinc.com/specs/30000to30099/pdf/nte30030_36_44.pdf