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geekhack Community => Keyboards => Topic started by: strict on Thu, 13 February 2014, 22:37:54

Title: LEDs for Phantom
Post by: strict on Thu, 13 February 2014, 22:37:54
I want to buy one of the Phantom PCB's from MechanicalKeyboards but before I place my order I'm trying to put together a list of all the parts I'm going to need to complete the build. The items I'm struggling with are surrounding the LED configuration. I would like to have white Filco style LEDs but I cant figure out which LEDs, resistors, and stand offs I need. I've been looking around on Mouser and Digikey but I don't know enough about what will or wont work to make a confident purchase.

Does anyone have part numbers that I could use on Digikey or Mouser to get the right parts I need? Ideally I would like to order all these parts from just one retailer to cut down on shipping costs.

For reference, here's the list of parts I've compiled so far:
Title: Re: LEDs for Phantom
Post by: Melvang on Thu, 13 February 2014, 22:40:20
For LED's I would recommend 2x3x4 rectangular LED's.  And the resistor will depend on the voltage of the LEDs.  There are 3 common voltage ranges which are usually certain colors.  There may be some odd ball ones but I am not real familiar with that.
Title: Re: LEDs for Phantom
Post by: Proc31 on Fri, 14 February 2014, 10:11:47
Check this thread for the LED Stand offs

http://geekhack.org/index.php?topic=46758.0
Title: Re: LEDs for Phantom
Post by: strict on Fri, 14 February 2014, 12:52:52
Quote from: Proc31 on Fri, 14 February 2014, 10:11:47
Check this thread for the LED Stand offs

http://geekhack.org/index.php?topic=46758.0

Those are exactly what I'm looking for. Does anyone have a part number for those or know what their length is? Ideally I would like to order them from Digikey or mouser since I'm already going to be placing an order with them.

Would something like this work for the LEDs? - LTL-4266N LED WHITE CLEAR 1100MCD T1 (http://www.digikey.com/product-search/en?mpart=LTW-42NC5&vendor=160)

Assuming the above LED will work, I followed the formula on the Deskthority wiki Phantom guide (http://deskthority.net/wiki/Phantom_instruction_guide) for calculating the needed resistance.

R = (5-V)/I
R = (5v - 3.5v)/0.020A
R = 75 ohm

However, according to this LED resistor calculator (http://led.linear1.org/1led.wiz) I should be using an 82 ohm resistor. Im guessing a 5% tolerance is okay?

Which one should I go with?
CF18JT75R0 75 OHM 1/8W 5% CF AXIAL (http://www.digikey.com/product-detail/en/CF18JT75R0/CF18JT75R0CT-ND/2022715)
CF18JT82R0 82 OHM 1/8W 5% CF AXIAL (http://www.digikey.com/product-detail/en/CF18JT82R0/CF18JT82R0CT-ND/2022716)
Title: Re: LEDs for Phantom
Post by: strict on Mon, 17 February 2014, 10:05:01
According to this thread I need 5mm diameter and 8mm length Components for building a Phantom keyboard (http://geekhack.org/index.php?topic=48032.0)

So I think these LED spacers might work SPACER MOUNTS LED T-1 .320" - Digikey (http://www.digikey.com/product-detail/en/7362/7362K-ND/316720)
Title: Re: LEDs for Phantom
Post by: whiskytango on Mon, 17 February 2014, 10:53:15
Just FYI, I calculated R for my pink phantom leds the same way, and they came out way too bright. Like blinding. You might not want to calculate with maximum current. I might suggest using 10mA or even less. Since resistors are cheap, you might order several values, and then test them before you solder them in. I think 220 and 330 are commonly recommended for the higher voltage leds. I have seen many people use much higher R values too.

FWIW, I also recommend soldering the resistors and diodes on the bottom of the PCB instead of the top so that if you need to remove them, you won't have to desolder the whole board to get to them. Then you can either desolder or cut the legs from the bottom without having to remove all the switches to take the plate off. WFD recommends this in his instructional youtube video for phantom assembly (very helpful by the way), and I found it VERY helpful when I realized my leds were way too bright and I wanted to change the resistor values.
Title: Re: LEDs for Phantom
Post by: damorgue on Mon, 17 February 2014, 10:56:12
Quote from: strict on Thu, 13 February 2014, 22:37:54
I'm struggling with are surrounding the LED configuration. I would like to have white Filco style LEDs but I cant figure out which LEDs, resistors, and stand offs I need.

Quote from: Melvang on Thu, 13 February 2014, 22:40:20
For LED's I would recommend 2x3x4 rectangular LED's.

That would be true if he wanted LEDs in the switches/under the caps. I interpret "Filco style LEDs" as if he wants the normal three LEDs in the case, in which case they should be 3mm round ones.
Title: Re: LEDs for Phantom
Post by: Melvang on Mon, 17 February 2014, 12:00:44
Yes, I stand corrected sorry for the bad advice.
Title: Re: LEDs for Phantom
Post by: strict on Fri, 21 February 2014, 13:42:39
Thanks for all the advice everyone.

I ordered the following LEDs - LED WHITE 7150MCD 3MM THRU HOLE (http://www.digikey.com/product-detail/en/VLHW4100/751-1502-ND/2403143)

For resistors, I ordered 3 each of 100, 180, 240, 300, and 383 ohm. Hopefully one of those will work to give me an acceptable brightness level.

For the LED spacers I just went ahead and got a half-dozen from jonathanyu in the thread that was posted above. It only cost $1.50 for shipping so I figured it was worth it to not have to mess around with ones from digikey possibly not working.

Now I just need stabilizers, a plate, and a case ...
Title: Re: LEDs for Phantom
Post by: strict on Wed, 02 April 2014, 19:42:51
Quote from: strict on Fri, 21 February 2014, 13:42:39
Thanks for all the advice everyone.

I ordered the following LEDs - LED WHITE 7150MCD 3MM THRU HOLE (http://www.digikey.com/product-detail/en/VLHW4100/751-1502-ND/2403143)

For resistors, I ordered 3 each of 100, 180, 240, 300, and 383 ohm. Hopefully one of those will work to give me an acceptable brightness level.

For the LED spacers I just went ahead and got a half-dozen from jonathanyu in the thread that was posted above. It only cost $1.50 for shipping so I figured it was worth it to not have to mess around with ones from digikey possibly not working.

Now I just need stabilizers, a plate, and a case ...

Just for the sake of documentation, I ended up using the above LED (VLHW4100) with a 180ohm resistor and am pleased with how it turned out. Using the TMK phantom firmware, I set the brightness level to 10 (out of 255) and its plenty bright so I probably could have gone with a much higher ohm resistor and been okay as well.
Title: Re: LEDs for Phantom
Post by: jdcarpe on Wed, 02 April 2014, 20:30:50
Did you already get the standoffs for the LEDs I'm assuming? I wish I had seen this thread earlier. I have a whole bag of those standoffs, and I would have sent you some for free.
Title: Re: LEDs for Phantom
Post by: strict on Wed, 02 April 2014, 20:35:01
Quote from: jdcarpe on Wed, 02 April 2014, 20:30:50
Did you already get the standoffs for the LEDs I'm assuming? I wish I had seen this thread earlier. I have a whole bag of those standoffs, and I would have sent you some for free.

Yep, I got like a half dozen or so from jonathanyu for the cost of shipping. Thanks though!  :)
Title: Re: LEDs for Phantom
Post by: zeroni13 on Thu, 03 April 2014, 10:35:09
Quote from: jdcarpe on Wed, 02 April 2014, 20:30:50
Did you already get the standoffs for the LEDs I'm assuming? I wish I had seen this thread earlier. I have a whole bag of those standoffs, and I would have sent you some for free.
I would like to get 2 standoffs, I totally forgot I needed those, haha. Even new Springs for the switches made it into my shopping list and those standoffs didn't, haha.