Fa-la-la display

I thought it would be fun to animate the refrain from "Deck the Halls" and my vision was something like this where each syllable stood on its own so it could be placed anywhere in the yard, could be any color and yet would not require a lot of wiring or take a million channels to control.

As each sign would have RGB capability, I decided it would be efficient to use "dumb RGB bullet" light strings instead of smart pixels (externally they appear to be very similar in shape and size) yet "dumb" RGB strings need only 3 control channels for the entire string whereas smart pixels require 3 channels for each light in the string. "Dumb" bullet lights can easily be mistaken for the "smart" WS2811 pixels, but generally speaking, you'll find that the "smart" pixel has a longer body and may have only 3 wires while the "dumb" style always has 4-wires. (Note that "smart" pixels sometimes also use a 4-wire mechanism, so exercise caution when working with bullet-style lights...)

I decided that it would be efficient to use pixel technology because of the convenience of the wiring and structure of the WS2811 auto-addressing mechanism built into "smart" pixels. However, the WS2811 chip can't accommodate the larger current requirements of multiple RGB LEDs connected together, so I devised a "Pixel-SSR" which used a single WS2811 chip that controlled a three-channel DC SSR because there would be many more LEDs to control than just a single RGB LED, which is what the WS2811 chip is designed to do. So the DIGWDF Pixel-SSR was born and a set of 9 assembled, one for each of the 9 syllables:

9 pieces of coroplast measuring 16" x 16" were cut from a single 8'x 4' coroplast sheet and 7/32" holes drilled through them to hold the dumb RGB bullets snugly. A master template (drawn freehand) was made so as to position the holes in consistent locations for each of the "la" syllables.

To minimize the wiring, each Pixel-SSR was fitted with a short female input connector and a 6' long wire with a male connector (output) soldered onto the end. The long wire afforded an easy way to space the syllables apart a distance, making each element self-contained and ready to connect to the next one without additional extension cables.

Nine frames were constructed using inexpensive framing-grade 1x3 pine. To form the boxes, thirty-six 15-1/2" lengths were cut and assembled using wood glue and sheetrock screws. The finished frames were 16-1/4" square, slightly larger than the coroplast panels, allowing for construction anomalies... (We weren't building furniture and there was no need for all measurements to create a perfectly square box. We deemed "close" as good enough for our needs...) Following the setting of the wood glue, 1/4-20 6" bolts were installed in what would be the "bottom" of the each box -- these would become the built-in stakes that would serve to hold each box vertical. The boxes were also painted white to match the coroplast material.

The electronics were installed using super-sticky foam tape. Being the first syllable of the refrain, the "fa" box received the DIGWDF MiWiFi controller with ESP module and Pixel-SSR (left photo) while the "la" boxes were fitted only with a Pixel-SSR (right photo).