G'day guys, just wondering how many of you intend on creating fancy light-shows for Christmas/New Years? Share your ideas.

Hi Aceslick911,

I'm visiting my parents for the holidays, and my Mom has outfitted her Hundai Santa Fe with reindeer antlers and a red dot in front for Rudolph's red nose. I was thinking of making the red nose light up on command with LEDs. I just need to figure out if that is legal (to have red lights in the front of the car), and whether I want to try to tap into the cars power system or not.

That is my little side project, I look forward to hearing everybody else's!

Humberto

I'm thinking about turning each of the fence pickets at the front of my house into a LED column and displaying messages across the front fence at night. I will only have 2 days to pull it off after my Nerdkit gets delivered tomorrow (hopefully) but hey theres new years after too right?

I THINK THAT IN MOST STATES A PRIVATE VEHICLE "CAN NOT" DISPLAY ANY "RED" LITES ON THE FRONT. ON THE POWER ISSUE I USE A 12 VOLT BATTERY ALL THE TIME ON MY NERDKIT WITH THE 5 VOLT REGULATOR.. MY TRACTOR SLED MONITOR AND THE REMOTE BOTH USE 12 VOLTS. MAKES NICE TO HAVE 5V FOR THE MCU AND 12V FOR LITES ETC....

MERRY CHRISTMAS ALL

JIM

um THANKS JIM mind the caps please.

Hey Aces, I thought a big marquee would be cool as well. I don't have a fence (which I love that idea) so I was thinking of either hanging it on the front of the garage or spanning between trees. I just wasn't too sure if an individual LED would really show up very well when spread out. Then I thought if I could make each pixel an LED cluster of maybe 3 LED's or, get the big 10 or 20mm LED's they would show better... Problem there would be power draw.

What were your ideas for the display? Were you planning on the regular 5 X 24 pixel (Original LED_array)?

Once you get your display up, show it off! I'm dying to see how it would look spread out over a picket fence.

Rick

G'day rick. It's just Ace thanks. This will probably need some experimentation.

Its a white picket fence so that should help with increasing brightness but I will have to see how well 1 LED shows up at night. The concern would be not just if it is visible but if 'patterns' are visible. If the lights are spread out too much. "merry xmas" would just look like a random assortment of lights.

I really dont know how I'm going to pull this off exactly but my idea was to either have alot of long wires and use a single 9v power source or, if that proves to be inadequet, maybe some kind of relay system. If relays were used, I could even use more powerful bulbs but I have no experience in that area so I'm just going to take this 1 step at a time and perhaps get some of the communitys help when i hit a wall...

What do any of the experienced members have to say about such a project? are there any components/strategies that you would reccomend for displaying messages across a large picket fence? (approx 10m across)

I think one of the biggest hurdles you'll have to cross will happen if you have to grow from the original single LED/pixel build. I think the use of relays for the display would not work for two reasons.

1. They are too slow. The display refreshes quicker than the mechanical ability of a relay.
2. The display as written depends on a Tri-State output. This is how the software in the mcu can turn off rows and alternating columns without affecting others. Relays are ON/OFF devices and could not provide the +/-/Z that is needed.

I have looked to see if there are any, for lack of a better word, "Tri-State LED Drivers" but have not found any thing that could help. A device similar to a UDN2003 only with Tri-state output would be great. It could provide a higher current flow allowing the use of larger/multiple led's per pixel. (Keep in mind this is just me thinking out loud) :D

This is one of the reasons I have thought of building a different variation of the marquee. Just a bit short of time right now. Maybe after the holidays...

Would it be silly for me to suggest to place a transistor or a relay at each 'pixel' point of the original led array design and then wire up higher powered light sources/clusters?

i've never experimented with relays, whats your experience with them? why are they slow? how slow exactly?

Keep in mind Ace, I'm a hobbyist, so my info may not be 100% accurate. I'll give it my best though. Relays (at least standard relays i.e. Not Solid State relays), are electro-mechanical. This means there is a delay between the coil being energized and the mechanical portion traveling to close the contact. This time will vary relay to relay but is significantly slower than the switching speed needed for the display.

A single transistor to my knowledge cannot provide a tri-state output. It will either provide a +/z or -/z . The current method used in the NK display utilizes a +/-/z output on all rows and columns. This was done to allow the doubling of the # of columns by adding the alternate reversed LED's.

This has been my holdup...

I ended up getting everything working with the relays (only used 4 because they're bloody expensive) i dont think they're quite solid state because they still 'click'

i was going to post a youtube video of my project to show off here but my delphi controller program kept crashing to the point i abandoned it :(

soo anyway turns out im a nerd and didnt abandon the project.... got it working albeit a bit messy and not the simplest solution lol.. but hey here it is! hope you all enjoy :)

The software i developed pulls feeds from twitter, uploads a 'movie' array to the device, sends messages and then streams commands on a continuous loop from a laptop.

lots of laptops (at one point i had two connected) cables and wires and multiplugs later, viola it was complete.

heres the link i hope you enjoy!

http://www.youtube.com/watch?v=XVl_VtDa34s