Comments on: Wireless RGB light bulb

By: Jack

Jack — Tue, 22 Sep 2009 12:07:32 +0000

Bulbs…? Don’t they grow out of the ground….Oh you mean a lamp! lol

By: Bill Hates

Bill Hates — Tue, 22 Sep 2009 04:18:36 +0000

just giving you a hard time sprite…. I like the hack!

By: Sprite_tm

Sprite_tm — Mon, 21 Sep 2009 17:24:42 +0000

Nope. The internals of the lamp still are intact; I could put 220V on it and have some light if I wanted.

By: ino

ino — Mon, 21 Sep 2009 17:16:45 +0000

My guess is he removed the ” tube ” from the pcb. No need to break it.

By: ctabm

ctabm — Mon, 21 Sep 2009 15:01:06 +0000

Just wondering- didnt he break open a cfl which contains a small amount of mercury?

By: ino

ino — Mon, 21 Sep 2009 10:19:43 +0000

Oh ok, I see. Buck converters aren’t easy to design when you’re looking for efficiency.

You should check on Dx, there’s a converter delivering 650mA under 3.6V. It’s almost perfect for this kind of application and around 3 bucks.

By: Sprite_tm

Sprite_tm — Mon, 21 Sep 2009 08:52:53 +0000

Oh, to add to my previous post: why the 1/3th duty cycle? Because the leds have a different forward voltage, which means I still would have to use series resistors if I wanted to turn them all on at the same time. By switching them on one at a time, I could use the buck-converter to adjust for the difference.

By: Sprite_tm

Sprite_tm — Mon, 21 Sep 2009 08:50:19 +0000

Ino: I tried that… but unfortunately all the components had such losses that I couldn’t reach the needed 1amp to light the leds fully at 1/3th duty cycle. That’s why I took this approach.

By: ino

ino — Sun, 20 Sep 2009 21:16:55 +0000

Ok, it’s a nice design but he could have done this less complicated with only one buck converter for the 3 leds and 1 transistor per led for pwm.
Simpler, cheaper, better efficiency and way less noisier.

Anyway, for a first, it’s quite good.

By: andrew

andrew — Sun, 20 Sep 2009 19:19:46 +0000

i have to agree, sprite_tm never fails to deliver good hacks.

By: just some nerd

just some nerd — Sun, 20 Sep 2009 18:42:39 +0000

why is there no heatsink ? besides this its nice.

By: thedudefrommiamivice

thedudefrommiamivice — Sun, 20 Sep 2009 17:35:13 +0000

I did something similar after seeing the one on thinkgeek.

By: hpux735

hpux735 — Sun, 20 Sep 2009 17:35:11 +0000

Nice work!

Honestly, even with the wires and circuit board hanging out it’s more attractive than the thinkgeek bulb. ;)

By: jomegat

jomegat — Sun, 20 Sep 2009 17:15:11 +0000

yes, yes, but this is HACKaday.

excellent hack as always from sprite_tm

By: Bill Hates

Bill Hates — Sun, 20 Sep 2009 17:08:30 +0000

Looks familiar…

http://www.thinkgeek.com/gadgets/lights/831e/

Nine bucks more and you get a five watt LED..