Welcome to the MacNN Forums.

Darksilhouette · Apr 30, 2001, 12:55 AM

I have a G4 with the old green LED and want to change it to a different color. I know the how for the most part... I was wondering if anyone had any helpful experience they'd like to share- like has anyone successfully done this? I looked at the LED itself and it's soldered to a board by 3 wires (3rd a ground?) finding this type of replacement is very difficult an possibly unnecessary. Comments?

Cipher13 · Apr 30, 2001, 02:21 AM

If Apple has it that way, I'd leave it that way... with the probs associated with power switches, I'd take no risks if I were you.

I know its just the LED, but its probably not a good idea having it ungrounded nonetheless...

If you can't find a 3-prong LED, well... look harder

Cipher13

------------------
AIM: Cipher1387
ICQ: 48111606
mail: cipher13@mac.com

pjkim · Apr 30, 2001, 07:02 AM

It is not a grounded LED. Why the heck would you need to ground an LED?

It is a two-color LED; two LEDs with either a common anode or cathode. You apply current to the other two leads and can get two different colors. I'v noticed that some iMacs LEDs are orange and green. Yours may be also.

Peter

sine -''-..- · Apr 30, 2001, 07:09 PM

zing ^_^

pjkim is rite, bi color led...
the third is most likely a common, the other two are the hot for each of the led colors. so if you were to change the led, you can use another bi color (although they really only come in red/green), or you can wire up a single led (i highly suggest white). if you were to do that, you [/i]could[i] wire up a blinker so that instead of lighting red, it will blink the single white. (a la the new macs)

Darksilhouette · May 2, 2001, 01:37 AM

cool. if it's that easy then i just might do it.

COmie JOe · May 2, 2001, 03:24 PM

My friend did it, it is a Bi-color LED, you can get them at radio shack. I did the same thing with my 7600 and 6500.

Cipher13 · May 2, 2001, 09:13 PM

Hm... I'll give it a go if I can find some nice coloured LED's

Cipher13

------------------
AIM: Cipher1387
ICQ: 48111606
mail: cipher13@mac.com

olePigeon · May 3, 2001, 08:01 PM

I think you should pick up one of those White LEDs they use in Flashlights and Cars now. When you turn your Mac on, it'll have a beam of light coming out of it.

Then you can tell people it's a security laser. If they interrupt the beam your Mac will arm a warhead and they have 20 seconds to get out. Who needs voice recognition?

Darksilhouette · May 4, 2001, 02:28 AM

NICE!
I think I'll get one of those super bright reds.
My G4 will be like no other...

itomato · May 4, 2001, 04:13 AM

I go for the blue ones, personally. They are outrageously expensive (relatively speaking), but oh, so cool. I put them in everything. One in my G3, 3 in my PC, and I'm putting one in my R/C transmitter..

Make sure you get one for the right voltage. I had a 5V one that wouldn't work with the G3.

------------------
-- | T () /\/\ /\ T () --

Cipher13 · May 5, 2001, 07:48 AM

Originally posted by itomato:
I go for the blue ones, personally. They are outrageously expensive (relatively speaking), but oh, so cool. I put them in everything. One in my G3, 3 in my PC, and I'm putting one in my R/C transmitter..

Make sure you get one for the right voltage. I had a 5V one that wouldn't work with the G3.

How much are they?

What kinda colour combinations are they available? Any if you look hard enough, or limited?

I mean... it'd be cool to get a blood red/blue one...

Cipher13

------------------
AIM: Cipher1387
ICQ: 48111606
mail: cipher13@mac.com

itomato · May 5, 2001, 02:43 PM

Well, at Radio Shack (no Fry's in the area..

) blue ones are US$2.99 each. The rest of them are usually under $1..

Plus, you could try any online electronics house or Digikey. If they don't have it, it's really hard to find.

------------------
-- | T () /\/\ /\ T () --

[This message has been edited by itomato (edited 05-05-2001).]

Darksilhouette · May 5, 2001, 03:35 PM

So, itomato, what IS the RIGHT voltage if it's not 5v? Good call though. This is something all of us were overlooking...

itomato · May 5, 2001, 04:03 PM

I guess I overlooked this when I posted

The Radio Shack 5mm 3.7 volt 20mA 2600mcd Blue LED is what I used. The Radio Shack part # is 276-316.

I had a 5v one on hand that works fine in the PC, and in the back of my optical mouse, but not in the Mac.

On a side note, the 5V LED is *super* bright. When all the lights are off, it will light up the wall on the other side of the room!

------------------
-- | T () /\/\ /\ T () --

Darksilhouette · May 5, 2001, 09:13 PM

Now, correct me if I'm wrong, but the brightness of the LED is measured in MDC's right? So for example a 1200 MCD LED would be much brighter than a 300 MCD LED. Is that how that works? I'd like to be able to pick out the brightest one possible.

itomato · May 5, 2001, 10:58 PM

Right - mcd is Millicandela. The Candela being a measure of the amount of light given off by a piece of platinum heated to... Aw, hell.. 1 candela is the amount of light given off by a candle. Probably the old fashioned tallow jobs.

2600mcd is considerably bright. Imagine 2.6 candles in that little 5mm bullet. Of course, it gets diffused as it travels through the light pipe, so it's a little less at the button.

You should be able to source a super bright LED that meets the requirements of the G4 if you really want a blinding one up there.

------------------
-- | T () /\/\ /\ T () --

Darksilhouette · May 6, 2001, 04:01 AM

So itomato, how did you get you led's off the chip they're on in the G4? They're attached pretty close. I don't want to damage the chip in any way obviously because it's the power/reset buttons at stake! any suggestions or tips?

itomato · May 6, 2001, 11:28 AM

I don't know. I don't have a G4. If it's soldered to a little PCB, then you'd have to take the solder off the back, remove the old LED, and solder the new one on in its place. Pretty simple operation if you're reasonably handy with a soldering iron. Lemme look and see if I can find the tech docs on the G4, and see what the LED connection looks like..

------------------
-- | T () /\/\ /\ T () --

Darksilhouette · May 7, 2001, 01:28 AM

Upon much closer examination of my older G4's green LED I realized that the 3rd wire comming out appears to be connected to nothing! (in terms of power supplies) It looks as if it is just a piece of metal set to give some lateral stabilizing. So the dual color LED theory may be unfounded... fyi.
It also is apparent that the LED is set so close to the chip that getting a soldering iron unerneath to reach it's connecting wires would almost be impossible withouth touching (and therefore burning) the attached chip. My initial thought is to use a very fine dremmel tool to slide underneath and cleanly cut the connectors.
thoughts?

[This message has been edited by Darksilhouette (edited 05-07-2001).]

May 9, 2001, 02:53 AM

@Darkshilouette:

If you think that the third isn't for the second colour, then how do you think it will be achieved?

My G4s Power LED is either steady green, when the thing is powered up, or pulsing orange, when the machine is in sleep mode.

Darksilhouette · May 10, 2001, 03:08 AM

to sniesen:
Who knows. I'm just commenting on what's in my box. My LED has never been anything but green. My third wire seems to be connected to a bare section of the wafer (i.e. no line to it)
I don't speak for anyone's machine but my own.

JoeG4 · Jan 21, 2002, 06:55 AM

I like the G4 LED's.. they are white and blink so smoothly

ibookuser2 · Jan 22, 2002, 01:34 AM

Remember that some printed circuit boards have multiple layers of tracings that are between the top and bottom layers that you see. The LED might be connected to a tracing in the middle of the board.

It is also *possible*, although uncommon, to have an LED that lights one color when current is applied in one direction, and a different color when current is applied in the opposite direction. In most applications, though, this is highly impractical.