DiyLightAnimation
Hardware => Lynx Smart String => Topic started by: chrisatpsu on December 23, 2012, 12:21:09 am
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Decided to start this with the ideas for next year.
Smart Meteors
Smart Icicles
Smart Strobes (thanks to zwiller)
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hmm after this year's fun
Maybe you should have a project done before you talk about it LOL
besides that I am curious about the Smart Icicles the most
Rick R.
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well, i throw out the idea, in case others might have ideas, and keeping it all in one thread, i can keep track. sorta like a journal.
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Start on them now! ;)
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Smart strobes ?
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Start on them now! ;)
I have to wait at least until after my daughter's birthday (Jan 2nd)
Smart strobes ?
Yes, Smart Strobes.
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Strobes:
So like 0 is off and 1 to 255 is the number of flashes in 30 seconds or something like that?
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While I like my Xenon strobes, if they were 3 watt LEDs? Perhaps 2 of them inside a C9 cover for light dispersal?
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Strobes:
So like 0 is off and 1 to 255 is the number of flashes in 30 seconds or something like that?
0-255 intensity level on a high power LED (not aetherII high power), possibly RGB
I'm not impressed with the meteors/icycles or strobes I've seen so far.
Xenon strobes really weren't bright enough compared to the hype I hear about them.
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After realizing the projects for this year, i guess meteors and icicles are essentially the same?
if there is any difference, i guess it would be the length?
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Xenon strobes really weren't bright enough compared to the hype I hear about them
are you looking at them with you sunglasses on? 8)
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Yeah, I have xenon strobes and they are bright.
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i was planning on smart icicle strings for 2013 for snow, meteor, and matrix effects. But after coming back from the Osbourne light show at Disney, I want to go full on curtain strings on my house.
Just worried if the software/hardware we have currently will support multiple universes of pixelnet. Whats the most pixelnet channels running that we currently know about? without issues.
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Decided to start this with the ideas for next year.
Smart Meteors
Smart Icicles
Smart Strobes (thanks to zwiller)
I second the icicles and strobes. I was actually already planning on converting my LightShow icicles over to smart icicles next year. They look really pretty, but I can't do much with them in a show, so I was thinking of taking out the existing led strip and replacing it with a smart strip. Shouldn't be too hard.
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Strobes man... Strobes.
Xenons are probably bright enough enough but it's the other issues... Moisture, lack of randomness, and cost. I was half tempted to try some xenons this year but I was glad I didn't since it was a very wet season for me. I don't think t here is any argument that the xenons will outperform led options but not without the aforementioned issues.
Initially I wondered if there was a way to create a system that uses 3 dmx channels to control speed, randomness, or duration. The Aussie folks have a couple of options just thought we could too.
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with linking it to a SSC, you could control the precise moment it turns on, or even keep it on, as a brief mini bust of light. (think stars in the sky kind of thing) and even slowly fade them. I'll experiment with some different led's this year.
Xenon, yes are bright, but not as bright as i thought, and I think i can get some led's that would be comparable
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I have a 800 watt DMX strobe I used in my Halloween show and it uses 2 channels of DMX (Speed, Brightness) but I have seen others that use 3 (or more if they have color filters) what it will come down to is price vs features for the design.
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placed an order for the leds to work on the strobe prototype.
trying for rgbled right now just to start.
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how many lights is a good count for icicle lights? what about meteor lights?
how long should they be?
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Icicles would be 10 to 12 LEDs, Meteor tubes 56 gives you a 4 foot tube at least when I made my FAST tubes that how long my 56 LED tubes where. YMMV
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I ordered some stuff to work on this year's projects. I wanted to get the order in early so i could beat the Chinese new year.
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While waiting on my items, I've found that a PNP tranistor (instead of two NPN transistors) has simplified my ciruit to control greater current, so this is a plus for the design.
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More P O W E R! <pop..
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i was planning on smart icicle strings for 2013 for snow, meteor, and matrix effects. But after coming back from the Osbourne light show at Disney, I want to go full on curtain strings on my house.
Just worried if the software/hardware we have currently will support multiple universes of pixelnet. Whats the most pixelnet channels running that we currently know about? without issues.
This year i had 24 universe and 12,100 channels.
Etherdongle => (3) 16 port hubs
I had no issues. I think i might exceed the 16K channels limit of 4 hubs so i have a second etherdongle to run the next 16K channels.
I used xlights to run my show.
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Any chance we get a C7 or C9 smart string??
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Any chance we get a C7 or C9 smart string??
ray has covers for the smart strings that make them the size of c9s
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how many lights is a good count for icicle lights? ....
When you say icicle lights, I think of my 3 meter long strings of 100-ct M5's on white wire with drops of 5,4,3 and 2 LED's spaced 100mm apart. But I guess that's not what you're thinking Chris?
...Meteor tubes 56 gives you a 4 foot tube at least when I made my FAST tubes that how long my 56 LED tubes where. YMMV
Jeff, I searched for FAST tubes with no results. Do you have more details?
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drops of 5,4,3 and 2 LED's spaced 100mm apart.
that's the kind of info I was looking for... i wont know the span, until i factor in the drops...
of course, if i made them even number of drops, then i can do nutcracker matrix effect with them...
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^ you mean like the same number of LED's per drop? If so, then this would be somewhat like a curtain, but short? say 12 to 18 inches? I wish my icicles had even a drop of intelligence.
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Jeff, I searched for FAST tubes with no results. Do you have more details?
FAST = Finally Affordable Snowfall Tubes
Link over at DIYC
http://www.doityourselfchristmas.com/wiki/index.php?title=FAST_Finally_Affordable_Snowfall_Tube (http://www.doityourselfchristmas.com/wiki/index.php?title=FAST_Finally_Affordable_Snowfall_Tube)
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I was thinking too much about how to make at least semi-smart icicles and getting nowhere except tangled up in lots of wire and splices. Then I saw this http://doityourselfchristmas.com/forums/showthread.php?25085-RGB-Chasing-Icicles-(Video)&p=256246#post256246 (http://doityourselfchristmas.com/forums/showthread.php?25085-RGB-Chasing-Icicles-(Video)&p=256246#post256246) and the light turned on.
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Regarding the icicles, I have been very happy with my two smart strings in one clear PVC for this years arches. So, I have decided to build some 3ft icicles. I have the PVC cut and the smart strings cut. I will be assembling them in about 2 weeks. Then I will do some pictures.
Rick S
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my idea for the icicles is to have the control chips in the top of the tube, with wires running down to the actual leds in the tubes.
using the 1" pvc to hold the chips and resistors, then a reducer to a clear plastic tube to hold the leds.
some people do the up/down method, but then are limited to how long they can run their icicles.
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Any chance we get a C7 or C9 smart string??
Ray Wu carries these snap on faceted C9 covers $11.58/100. You slip over the standard 12mm pixels and Voila, instant C9 smart string. http://www.aliexpress.com/item/faceted-White-C9-covers-100pcs-set/506253078.html I've tried them out and they look fine but can fill with water, so be sure you are using IP68 strings.
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Was thinking of this idea last week and was trying to think of a way to get a good "icicle" look during the day. Had some in the past that I used hot glue on with incan and they turned out well, but weathered and turned yellow over the years. Thinking about maybe using acrylic and melting it and allowing it to drip on tubing to create look. Not sure, will have to test once I get to this project to figure it out.
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my idea for the icicles is to have the control chips in the top of the tube, with wires running down to the actual leds in the tubes.
using the 1" pvc to hold the chips and resistors, then a reducer to a clear plastic tube to hold the leds.
some people do the up/down method, but then are limited to how long they can run their icicles.
If I get you Chris, by "how long" you're saying that the "limit" is the number of LED's that the chip can handle? In the case of your arches the limit was nine 5050's per chip, right?
I have an idea about icicles/meteors but little practical know-how. I don't wanna hijack yours so I'll start a new thread.
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someone had this idea...
http://diylightanimation.com/index.php?topic=8504.msg121176#msg121176
which involved the nodes dropping to a certain length, then regular wire running back up...
the issue is the length of the return wire is limited as you can only have so many feet between nodes.
my idea is to have the ssc wire come into the top into my circuit board, then exit, and move onto the next icicle.
inside the icicle, the circuit board connects to the rgb leds in the tube to make the icicle...
now the length limitation is only between icicles.
Red,Green,Blue wire is the wire coming from the SSC.
Orange is the circuit board(s)
Purple are the leds in the tube
Maroon (thin) are the wires running to each led.
(http://i1059.photobucket.com/albums/t438/chrisatpsu/idea1_zps4a4af890.jpg)
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i just wish, smeighen can allow a matrix to be programmed from the top right and run vertically.
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i just wish, smeighen can allow a matrix to be programmed from the top right and run vertically.
Horiz targets this year will allow you to start in any corner
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hanging icicles woud be verticle. So, i'm still hoping !
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Seems like a good idea but $$$$, I would think it would be easier and cheaper to just put a node (skip that node in sequencing ) in the wire if the run is over 6'. Just saying the cost of one node is a lot cheaper that the cost of a SSC.
just my 2 cents
Rick R.
someone had this idea...
http://diylightanimation.com/index.php?topic=8504.msg121176#msg121176
which involved the nodes dropping to a certain length, then regular wire running back up...
the issue is the length of the return wire is limited as you can only have so many feet between nodes.
my idea is to have the ssc wire come into the top into my circuit board, then exit, and move onto the next icicle.
inside the icicle, the circuit board connects to the rgb leds in the tube to make the icicle...
now the length limitation is only between icicles.
Red,Green,Blue wire is the wire coming from the SSC.
Orange is the circuit board(s)
Purple are the leds in the tube
Maroon (thin) are the wires running to each led.
(http://i1059.photobucket.com/albums/t438/chrisatpsu/idea1_zps4a4af890.jpg)
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after some new developments, i think i can put this together for much less work than the smart arches, and still cost less than getting smart string nodes.
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after some new developments, i think i can put this together for much less work than the smart arches, and still cost less than getting smart string nodes.
I'm all in. Do you want the measurements for my house now? >:D
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the last items of my first prototype (strobes) have shipped, so we'll see how this turns out.
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I found this website about a month ago: http://www.lightuplawrence.net/Home/how-to-1/rgb-dmx-pixicles
He is really what gave me the bug to look into pixels and rgb stuff. I like how he has one "keycicle" that a couple "pixicles" mirror from. I'm not sure if this would work with a SSC but it might give you an idea??
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Chris,
You probably already saw this but just in case:
In Development - Pixel Strobe Controller
http://auschristmaslighting.com/forums/index.php/topic,3643.0.html (http://auschristmaslighting.com/forums/index.php/topic,3643.0.html)
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i just read it, and it seems overworked.
We'll see when I get my parts in, but it seems like it doesn't have to be so complicated... <fp.
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parts came in today, so i might have something worked up tonight.
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parts came in today, so i might have something worked up tonight.
For your strobe?
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yes
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sweet can't wait, still would like to do a strobe myself >:D
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actually a little set back. I forgot to figure out my resistor values, I'll have to wait in getting some 5watt resistors.
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parts came in today, so i might have something worked up tonight.
Everyone is on their edge of their seats waiting to see what it is………
actually a little set back. I forgot to figure out my resistor values, I'll have to wait in getting some 5watt resistors.
Now everyone falls on the floor ;D
Rick R.
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well, i'm going to attempt to build my own 5 w -(27 ohm) resistor by using 15 - (510 ohm), and 5 - (680 ohm) resistors connected in parallel. that should give me about ~27.2 ohms at close to 5 watts (really only need about 4.3 watts in resistance.)
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test control circuit
(http://i1059.photobucket.com/albums/t438/chrisatpsu/IMAG0376.jpg)
the LED, and covers once it's all done.
(http://i1059.photobucket.com/albums/t438/chrisatpsu/IMAG0375.jpg)
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it's actually getting so bright, it's distorting the camera!
due to my lack of resistors, i could only test colors individually. I couldn't test them all on for white, but so far, this will make a good strobe.
the blue is out performing my blue xenon strobes.
oh yeah, the picture was taken at a pretty low angle, it wasn't anywhere near straight on!
(http://i1059.photobucket.com/albums/t438/chrisatpsu/IMAG0379.jpg)
(http://i1059.photobucket.com/albums/t438/chrisatpsu/IMAG0378.jpg)
oh yeah, compare the same lighting level as the picture above (the one showing the test circuit)
meaning= i did not turn off the lights for this test!
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red 400 mA
green 350 mA
blue 350 mA
source voltage 12v
forward voltage
r 2.3
g 3.5
b 3.5
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Cool. Really wish I knew more about this stuff.
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estimated costs
about $2.00 per strobe (not counting wire, or connectors, or sealant)
and about 15 solder points (5 per color) per strobe...
doesn't seem too bad. a lot less work than the smart arches.
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Are you planning to control these like strings of pixels and manually strobe them using the sequencer of choice?
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Reminds me of the led used on aethers. Perhaps you can call them aether strobes.
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they would be high powered pixels 350-400mA per color as opposed to 11mA that the pixels use.
on off, and intensity would be controlled via the sequencer.
no sense in adding "features" and firmware for a pic, when it can all be run from the software.
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hehe, don't look into a 3watt rgb led while full on!
well, i know it's stinkin bright!
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$2 per strobe?
Does that include the led or is the decimal in the wrong place?
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Hi,
5W resisors are big and you'll need 3 in each strobe. How do you plan on placing these in your design?
Have you considered using 2 or 3 RGB LEDS in series to lower the voltage across the resistors?
Leo
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What about heat issues? or will the random firing ofset that.
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the 3w rgb leds are $1.30 each so that takes up the bulk of the price. the led is on a 20mm heatsink, and i can fit the electronics inside a 30mm plastic dome.
as far as placing these in series, i'll still need close to a 5watt resistor.
interestingly enough, all 3 colors use the same 27 ohm, 5 watt resistor. (the red is lower voltage, but uses more current)
Reminds me of the led used on aethers. Perhaps you can call them aether strobes.
the aether's led is bigger in size (and in the current it uses)
i think the aether's is about 28mm
this one is 20mm
Hi,
5W resisors are big and you'll need 3 in each strobe. How do you plan on placing these in your design?
Have you considered using 2 or 3 RGB LEDS in series to lower the voltage across the resistors?
Leo
there is plenty of space in the plastic dome to fit everything. I left the led cycling for about 30minutes, nothing got hot. nothing even got warm.
What about heat issues? or will the random firing ofset that.
by using 5watt resistor (which is well over the 3 to 4watts thats needed) there isn't an issue with any of the components getting warm.
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Very cool Chris.
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[quoteVery cool Chris] [/quote]
+1
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a little bit of a design issue though...
if they were powered by the ssc, there would be a limit of 3 rgb strobes per SSC as each strobe is about 1.1A
i could still power the circuitry via an SSC, and provide power to the LED's externally (kinda like trying to control a 5v device with an MR16)
so there would be the normal 3 wire connection between the strobes like the nodes have, but also a thicker 2 wire cable also bundled with it to provide the higher Amperage power. (so a 20 Amp power supply could run 14 or 15 strobes)
however, the nice side would be, you could have 128 strobes on a string, with each block of strobes getting it's power from a different source.
(or you can just break up the strings as you see fit)
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on, a side note, the icicles will be a lot easier (also a simpler design to the smart arches, that would make it easy for anyone to build)
each icicle would have just 8 solder points per led
the new smart arch design would have only 8 solder points per segment as well!
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Re: sequencing these. One thing I picked up in the aussie thread is the data rate with dmx/pixelnet is an issue for good strobe effects. I can vouch for this with testing my 10W spots. It might still be doable though. Great progress though!
How much cheaper/easier white only might be?
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i'll have to see how these respond to a sequence
i went the rgb route, since the control is coming from a tm1804 chip, and since it has the 3 channels right there, it made sense to go with the rgb led.
plus, i liked the flexibility to match the strobe effect with the color being used in the sequence.
white is possible. for 1watt, it wouldn't be as bright as the an rgb turned on full giving 3 watts.
and using 3 watt white, you might as well add that to one channel from an dsc, since i'd have to switch from a normal transistor to a MOSFET.
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since i'd have to switch from a normal transistor to a MOSFET.
Chris,
This is very cool stuff! This is going to be my first year and I'm loving all the cool ideas you are coming up with. As I'm still learning, I just wanted to confirm that the reason you'd have to switch to a MOSFET with a 3W LED is due to current draw? Just trying to learn as I go :)
Keep up the great work!
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yes
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Chris, if you are going the route of an external supply why not put in a constant current driver and eliminate the big resistors.
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Using DMX, you'll send an ON command, then an OFF command. The length of time between commands will be your strobe flash.
Or, do you plan a timing circuit that will turn it OFF at a fixed time (5ms, 10ms, 15ms) after it gets an ON command?
ps, if you severely limit the ON time, you won't need 5watt resistors. A normal 1/4 resistor would not get hot handling a 5ms pulse every 2 to 5 seconds.
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Smart Strobe running as 50ms. RGB (3 watts white, 1 watt per color)
some people don't like the timing of 50ms for a strobe. 50ms looks darn good to me!
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Tease says the video doesn't exist :)
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Ok, vimeo is acting up for me today, it's been almost an hour and a half...
here's the video on photobucket
(http://i1059.photobucket.com/albums/t438/chrisatpsu/th_strobes_zps1671db15.jpg) (http://s1059.photobucket.com/albums/t438/chrisatpsu/?action=view¤t=strobes_zps1671db15.mp4)
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What was the quick flashing at the start? Guessing the steady white flash is the 50 ms?
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at the beginning, it was flashing at different rgb values...
50ms intervals... R,off,r,off,r,off,g,off,g,off,g,off,b,off,b,off,b,off,w,off,w,off,w,off and repeat a few times.
the rest was a 50ms flash once a second.
so, is it too long?
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I think it looks great! I would love to see a test of running some together. 50ms might work.
Is there any to squeeze one more into the circuit for a total of 4?
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Ah ok I think the speed at the start is good enough for me. Only thing I can think of is some way to make it random for different ones to get the effect of strobes.
So I'm interested now, want to give build details :)
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50ms looks good. I think the repeat rate at the beginning is the key to its awesomeness. I dont know of any xenons that can come close to this.
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Ah ok I think the speed at the start is good enough for me. Only thing I can think of is some way to make it random for different ones to get the effect of strobes.
So I'm interested now, want to give build details :)
twooly, i totally made these strobes to be independently controlled. as far as the sequencer, think of them as just a plain old node.
i have the one strobe set up in vixen. each "strobe" takes 3 channels, R,G, and B. (all three make white)
the pattern you saw, was simply in vixen with a 50ms refresh rate. one block on, one block off, etc...
you can have total control when they come on. if you want to make a "starry sky" then you turn them on, and leave them on.
i left these on for a solid hour, and the heatsink was warm, but i could pick up the led without any complaint. (and wont be an issue for the plastic enclosure i had over the led.
I think it looks great! I would love to see a test of running some together. 50ms might work.
Is there any to squeeze one more into the circuit for a total of 4?
zwiller, i haven't played around with more than one "strobe" yet, as I'm still waiting on the 5watt resistors to come in.
i can have a string of 128 of these, just would have to provide a power injection, or a doubled up, or trippled up + and - wires.
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strobe node with plastic enclosure
(http://i1059.photobucket.com/albums/t438/chrisatpsu/IMAG0381_zps5646fd20.jpg)
strobe node without plastic enclosure
(http://i1059.photobucket.com/albums/t438/chrisatpsu/IMAG0382_zps4c41d1c5.jpg)
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When is the COOP? >:D
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on the left a C9 xenon strobe... on the right, my led strobe. trying to duplicate the effect of the xenon strobe.
(http://i1059.photobucket.com/albums/t438/chrisatpsu/th_VIDEO0032_zpse975d095.jpg) (http://s1059.photobucket.com/albums/t438/chrisatpsu/?action=view¤t=VIDEO0032_zpse975d095.mp4)
same thing, but showing that you can leave the led on full 100%
(http://i1059.photobucket.com/albums/t438/chrisatpsu/th_VIDEO0033_zpsde07e9bf.jpg) (http://s1059.photobucket.com/albums/t438/chrisatpsu/?action=view¤t=VIDEO0033_zpsde07e9bf.mp4)
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the camera doesn't give it justice, but the led is way brighter than the strobe.
I have a string of 6 of the xenon strobes, and the one led "strobe" is just really dominant.
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Very cool Chris! I am really impressed!
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it'll be about a month or so, but it'll really be worth it, as I'm working on a way that all of you can make these afford-ably :)
(I'm not selling these, I'll provide all the details how to get the parts t make them, and it'll be REALLY REALLY easy.
(also, i'll be able to show you how to make the smart arches really really easy to make also...)
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Awesome cant wait
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if i can come up with a "name" for these, i call shotgun for either "Nittany Lion" or "Lion" is keeping with the cat names lol.
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Very cool Chris. Nice work.
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ok, after using for a bit, i've come across a few things...
if i leave it on full 100% for longer than 5 minutes, the heatsink does get hot.
but as long as it's flashing, or using colors, it's fine.
also if i have on events of full white for 50% of the time or less, it's fine.
at 50% the heatsink isn't cold anymore, but isn't warm either.
in a show setting, i don't think this will be an issue, since i can't think of where someone would have it full on for more than say 10 seconds..
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Bump to see how this is going 8)
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In one of his most recent posts i do beleive he said he has been pretty ill :-[
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i'm still battling the flu.
I plan to solder the string together and give it a try :)
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Maybe the solder fumes will help clear up your sinus passages... >:D
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Get better Chris
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Hope you feel better soon Chris!
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Any updates on this? I hope you aren't still battling the flu.
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Any ideas on a heatsink for the RGB LED?
If I take the tabs off the side of the clear dome, It will fit inside the thinwall pvc that we used for the SSC's. But I'm open to ideas...
(http://i1059.photobucket.com/albums/t438/chrisatpsu/20160108_2105371_zpswk0zqief.jpg) (http://s1059.photobucket.com/user/chrisatpsu/media/20160108_2105371_zpswk0zqief.jpg.html)
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What do you want to use it for?
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What do you want to use it for?
This is the strobe project from this whole thread.
At short bursts, I don't need a heatsink, but as others build these, some will want to keep them on longer where they will generate heat.
Think of a song building to a loud ending. I scan see these flashing like strobes, then finally staying on the the very end, and slowly fading with the rest of the show lights.
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Keeping them on for any real length of time would not be practical in such a small enclosure. The problem with any heat sink is that they require enough airflow to disperse the absorbed heat. This is the reason for the current limitations on the LE and the size of the Aether. Packing the LED and heat sink into that small tube would give no air flow at all so you would need a heavy heat sink to absorb enough heat to be worthwhile. The problem is that it would also take a while for that heat sink to cool back down, especially with no air flow.
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Which is why I'm asking for suggestions.
I didn't require that it had to be placed in the tube.
I left the question open ended so that I could see what people would have come up with.
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With the example that you gave above, I would use a chunk of lead. The LED module needs to be attached to the heat sink so whatever the LED is in, the heat sink needs to be in as well. If you want to keep the unit small like using a SSC enclosure, I would go with mass over size (surface area) to give it the ability to absorb and store more heat.
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So you waited for the bottom of the rgb chip market to bottom before resurrecting this thread? >:D
For the cost of the led, I'd say just caution the user to keep duty cycle low... One could use RobG 10w floods if they want something that stays on more or all the time. I re-read the thread and thought heat was mostly non issue? Any chance you can eek out 4 with a 2811 chip? Will your design work for non-rgb?
2016 is year of the strobes for me. I just had a Komblinkin kit and RGBW board components delivered yesterday. Gonna be try all sorts of things. First thing is comparing sequencing a strobe effect to the komblinkin auto-random.
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I'm firing up this project again, because I know YOU sir, are desperately waiting for an RGB Strobe.
So you waited for the bottom of the rgb chip market to bottom before resurrecting this thread? >:D
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Any ideas on a heatsink for the RGB LED?
If I take the tabs off the side of the clear dome, It will fit inside the thinwall pvc that we used for the SSC's. But I'm open to ideas...
(http://i1059.photobucket.com/albums/t438/chrisatpsu/20160108_2105371_zpswk0zqief.jpg) (http://s1059.photobucket.com/user/chrisatpsu/media/20160108_2105371_zpswk0zqief.jpg.html)
I'm making a few RGB mini spots with a similar LED module so I was also looking for some sort of heat sink....
I was going to just use some aluminum stock (perhaps some 1" x 1/16" strip bent in a U shape) but then I found some on Aliexpress that looked like the may be better...
I had hoped they would fit the LED base but they don't exactly so I will have to do some drilling...
My plan is to mount them in 2" PVC tubes and run them off of a DMX constant current controller...
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You just gave me an idea. :)
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What is your idea????
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your heatsink idea
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With the example that you gave above, I would use a chunk of lead. The LED module needs to be attached to the heat sink so whatever the LED is in, the heat sink needs to be in as well. If you want to keep the unit small like using a SSC enclosure, I would go with mass over size (surface area) to give it the ability to absorb and store more heat.
Lead!? Um, no. Gravitational mass and thermal mass are two different things, and not always closely linked. The amount of heat required to raise the temperature of a unit mass of a material one degree C is called the specific heat of the material. Lead does not have a very high specific heat, meaning it only takes a relatively small amount of heat to raise its temperature a given amount. The specific heat of Lead is 0.13 KiloJoules / Kilogram * degrees K. (The same as gold, as it happens.) Copper is 0.39 and Aluminum is 0.91. Given its low cost and the ease of working with it, as well as its low corrosivity in dry air, Aluminum is just about the best choice for a heat sink if you want the material just to heat and cool slowly. There are a number of metals that are much better, but cost much more and are harder to work and maintain:
Beryllium - 1.83
Lithium - 3.57
Sodium - 1.21
Iron and Steel aren't too bad, running around 0.5.
For a heat sink, however, one wants not only a large thermal mass, but also a low heat conductivity. If the heat conductivity of a material is high, then even though it may have a high thermal mass, it may not tend to stay cool near the component, which is what is important. The temperature near the component will rise quickly, while the rest of the mass remains cool for a much longer time. Not only is the conductivity important, but also the total conductance, assuming the heat sink is not a closed system. In general, the heat sink acts as both a buffer and any or all of a radiative, conductive, or convective transport to an infinite medium such as air, water, or space. To this end, in general the smaller the distance from the heat source to the external medium and the greater the area of the sink in contact with both the source and the medium, the better. That is why your car radiator and your Air Conditional condenser coil is made of either thin copper or aluminum tubes attached to a myriad of very thin copper or aluminum plates. It gives the shortest possible distance between the coolant fluid and the surrounding air / space combined with the highest practical surface area to both radiate and conduct heat into the outside environment.
Aluminum has a fairly high thermal conductivity given its price - around 68 Watts / meter * degree K. Copper is much better at around 129, but copper is heavier, more expensive, and harder to work - with the exception of welding, brazing, and soldering, which is very easy with copper. Copper also tends to corrode more in dry air than aluminum. These facts are why one sees many PC cooling systems employ thin Aluminum fins as radiators along with copper heat pipes to transport the heat from the device contact plate (also usually copper) to the radiators.
Lead is very poor, at only 11.6. Even some Stainless Steel alloys (which are very poor heat conductors) are better than Lead. Indeed, there are not a whole lot of pure metals that are worse than Lead. The very best conductor of heat of all pure metals is Silver, with a heat conductivity of 136 W/(m x K). Gold is next, at 106. At this point one might notice the relative heat conductivity of the various metals and alloys falls fairly closely in line with the relative electrical conductivity. There is a reason for this. The mechanisms which produce thermal conductivity and electrical conductivity in metals have a number of fundamental processes in common, so the better a conductor of heat the metal or metal alloy is, the better a conductor of electricity it is also in general going to be, with Silver and then Gold being the best of both. Copper is very high up in the list, Aluminum is fairly high up the list, and Lead is at the bottom. OTOH, the mechanisms responsible for determining the gravitational density or thermal heat capacity of a metal have almost nothing in common with those responsible for conductivity.
Oh, and Lead is fairly expensive these days.