Extra LED Lights flashing a bit

[JohnStack]

Hi, when I do a print, my LEDs are pulsating at around 60 hertz. I have them coming off of one of the spare power lines, not off of the board.

They don't pulsate during idle.

Is there a way to stop the pulsating? (that's not a leading question @foshon !)

[cambo3d]

get an inline voltage regulator.

http://forum.seemecnc.com/viewtopic.php ... 270#p10128

[Eaglezsoar]

You could try to place a large value electrolytic capacitor where the LEDs connect to the power lines.
I question the 60 Hertz pulsation. The human eye would normally merge pulsations at that frequency
so that it would not be noticeable. The filament based electric light bulb receives 60 Hertz AC and few
if any people would notice the "flickering". Many computer monitors and televisions use a 60 Hertz refresh
rate for the same reason, the eye merges the images together and flickering is not noticeable. As Cambo3d
has noted, a voltage regulator would work but I would at least try the capacitor route, whichever is the
least expensive.

[cambo3d]

capacitor wont help in this case because the leds are constantly drawing power from a poorly regulated power supply already. capacitor cant keep up.

[Eaglezsoar]

After reading again Cambo3d's post about how he did his Led hookups, I had completely forgotten the Rambo
PID. The module he listed fixed his problem and should fix yours also. Good find Cambo3d!

[dbarrans]

Flickering is more visible with LEDs because they turn on and off very fast. Incandescent bulbs and monitors only get brighter and dimmer at 60Hz, so their flicker is less noticeable. LEDs are fast enough to turn completely off each cycle.

- dan

[JohnStack]

Thanks for the tips.

Guess I'm in the minority because see flickering everywhere but LED pulses are especially tough on me. Fans on low drive me nuts.

( ♫ I wear my sunglasses at night ♫, kidding)

[Eric]

You're seeing load-based voltage fluctuations/noise on the power supply. That's perfectly normal for most consumer PC supplies, within reason. There are capacitors and voltage regulators on PC motherboards and other peripherals to clean up some noise. That said, a significant number of PC hardware problems trace back to the quality of the power supply and or motherboard power regulation.

Your most obvious choices are:
a) A decent sized capacitor, the closer to the LED's in circuit the better. This will smooth out voltage spikes and valleys. I'd probably try whatever you have handy in the 300-500 µF range to start. You can loot handy junk electronics (power supplies, PC motherboards) if you are able to unsolder component and want free parts.
b) Voltage regulator circuit. The one cambo used includes TWO 470 µF 35V caps on it, if you look at his pix, and is overkill, but it works. You can find cheaper regulator circuits or build your own.
c) Completely separate power supply for the lighting. A wall-wart of the right DC voltage would probably work.

[JohnStack]

Thanks.

I hate my wife's ringtone on her blackberry. Maybe it has the right size?

I'll get one out of a cheap electronic alarm clock. I want the LED off of it anyway. Thanks.