Modifying a switch Part II

Tonight, since I had a bit of time, I really went ahead about my theory of changing the normal white LED inside the switch to the bi-colour (Red/Green) LED. This is so that my project does not need to have so much buttons and switches (because I do not have any power tools, so, making those holes will definitely kill/sprain my hands). Yeah, I decided to make maximum use of space and all switches will do double duty as visual indicators too.

In my hurry, I have destroyed the small white LED.
I should have waited for the soldering iron to warm up
so I can desolder the metal contacts from the tiny little
resistor and diode before I can remove the LED. Now,
I realised why the White LED is so dim. They used a
1.2K Ohm resistor for a 12volt input. Should have used
half the value and the LED would be brighter. Also, they
inserted a diode there in case some bright spark used
the wrong polarity. But I tell you, the resistor is so
tiny (~ 4mm), its a wonder they can fit in there.
Here is how its done.
A: There is a reason why the White LED was so small. It was designed as a 3mm LED but with the lens taken out. So, this makes it shines forward. I could not find a 3mm Red/Green LED replacement and so, with a 5mm LED, it was too big to fit in without being hit by the switch button cover.
B: So, I have to unplug the LED module, desolder the metal connectors, cut off about 5mm or so of the while plastic column, at the same time making sure the orientation of the new LED is correct. If the voltage passes is positive, I want it to be green and if its the wrong polarity, I want it to be Red.
C: Put in the new 5mm LED, resolder the metal connectors and plug in back to the switch. So, now, you have the new 5mm modified LED module.
D: Now, when I press the button, the big 5mm LED will not obstruct it.


This is how it looks when the voltage is correct

And this is how it looks when the voltage is wrong

As a precaution, I soldered the resistors on the legs of
the LED's solder lug. Sometimes, it's too easy to forget
what you have done when you revisit the project at a
later date. By then, you would have assumed it is OK
because the wrong label outside says the LED is rated
12 volts when it's not, and blow it to Kingdom come.

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