In the spring, we’re finalizing a design which has the LEDs / drive electronics safely encapsulated in an injection-molded enclosure which will look surprisingly similar to a C9 Christmas light.

However, tooling and setup fees for the machining will be very expensive.  Plus, it takes a long time.

Here’s how I impatiently but quickly weatherproofed the pixels installed on the house.  Click any picture to enlarge.

(Note that though this seems to work well, it took a long time and was fairly boring.  Won’t be doing it again.  Also, I wanted to use regular heat-shrink tubing to seal the parts.  Unfortunately, the header pins and LED are so bendy that nothing sufficiently wide would make a good seal.)

To start, take an assembled, tested and programmed pixel.

Then, buy a roll of Heat Shrink Film from your local professional print shop.  This is the same plastic that’s wrapped around CDs and DVDs from the store.  It came in a 500 foot roll 12″ wide.  If anyone needs about 485 feet of shrink film, let me know.

Buy a Foodsaver clone from Target for about $40.  Useful because it has a strip of heating element which we use to make custom shapes with the shrink film.

Make a bag, sealed on three sides, out of shrink film.  Mine was 12″ long by 3″ wide and open on the 3″ end.

Seal the fourth side.  The plastic ‘pillow’ is now air-tight.  Test the seal by mashing it with your finger.  At this stage it’s important that the circuit be isolated from the rest of the world.

Ever so gently, press the 10 pins of the ribbon cable through the film.  If you do it right, you’ll have 10 small punctures in the plastic.  Do it wrong and the film tears and you start over.

Use a heat gun to shrink the film.  It’s soft and supple when warm – almost like cellophane wrap.  When it sets, it’s crinkly and stiff.  Funny looking up close, totally unnoticeable from a more than a few feet away.

Attach the pixel to the ribbon cable harness previously constructed.  My lights are on 8″ centers.

For even more protection, use a 1″ piece of 3/4″ diameter heatshrink tubing to lock the female and male headers together.  Somewhat like a turtleneck shirt.

Et voila.  I wouldn’t immerse them in water, but it works well to keep off blowing snow and rain.

What a day!  This morning I drove downtown to get another 200′ of power and data cable.  I’d previously used 400′ of each for the two lower rooflines, the arch and the garden lanterns.

I finished and tested a second 8-way DMX splitter, because the upper and lower runs are assigned to separate universes.  Then, I weathersealed the remaining 100 or so pixels for the three upper runs.  

We started installing at 5:30 and were finished a few hours later.

The test pattern we ran during installation – and which is shown below – toggles between green with red sparkles, red with green sparkles and blue with white sparkles.

All told there are about 200 point source pixels and 19 ‘classic’ pixels mounted in the garden lanterns.

Click a photo once for medium size, then a second time to see in a larger size.

Will post video clips once I’ve found a 3-CCD camera that has decent dynamic range.

Here are some pictures I grabbed halfway through the installation.  

The low parts of the house are done.  The high parts of the house are terrifyingly out of reach.  Will work on those later this week.

There are 100 point source and 19 standard pixels in the garden lanterns installed so far.  That makes 357 channels of DMX-512.

Click a photo one for medium size enlargement, then a second time to see it full size.

[click to enlarge]

Half a pixel. Based on the original RGB design but with half the LEDs. 1.25″ square.

Bill of Materials:  

• B1  5mm blue led               
• B2  5mm blue led                        
• B3  5mm blue led                          
• C1  .1 uF 10v ceramic, 0805 package        
• C4  1 uF 10v ceramic, 0805 package       
• C5  10 uF 25v ceramic, 0805 package   
• E1  5mm red led                            
• E2  5mm red led                          
• E3  5mm red led                             
• G1  5mm green led                           
• G2  5mm red led                             
• G3  5mm red led                            
• JP1  .1″ x 5 pinheader, optional    
• JP2  .1″ x 5 pinheader, optional       
• PGM  .1″ x 5 programming header, optional       
• R1  1K 0805   
• R2  1K 0805    
• R3  1K 0805   
• R4 1K 0805      
• R5 300 0805       
• R6 117 0805     
• R7 100 0805     
• T1  2N3904  SOT-23 
• T2  2N3904  SOT-23   
• T3  2N3904  SOT-23  
• U$1 78L05 SOT-89       
• U1  PIC 16F688 SOIC-14                        
• U2  MAX485/SN75176 SOIC-8          

Here’s a small (but growing) collection of projects which include our DMX pixels.

mrpackethead from New Zealand sends this photo and video clip.  Pictured are 160 of the ‘classic’ RGB Pixels, based on daisy-chaining cat5 network cable.

If you’ve used pixels in a creative or exciting way, we’d love to hear about it.  Send your pictures, links or video clips.