Countdown Timer Build

[Aaron Maue]

Took a look at the threads that talk about a countdown timer, most for a timer between shows. I'm planning to put one into next year's show to provide a "Days 'til Christmas" timer.

After researching what was available commercially and finding one of two scenarios or both - either above my ability to build (lots of electronics circuitry, etc.) or too small to fit my purpose, I've decided I'm going to build my own and use LOR to drive the prop. What I'm going to do is build a 2-digit (7-segment each) day counter and use a controller to drive the segments individually. Sounds like a fun project that will allow me to combine my 2 favorite hobbies - woodworking and Christmas lights.

I'm going to build each individual segment "box" out of thin (probably 1/4") plywood, MDF, or whatever, deep enough to house a couple (maybe 3) C7 bulbs placed next to each other. I've included a very rough sketch below. The bottom of the segment will also be made out of the same material, with the wire for each socket passing through, or maybe the socket passing through. We'll see what works best. The top will be of some sort of plexi.

The input I'd like it this... I plan to use red LED C7s to replicate the color of a traditional 7-segment display. My plan is to paint the insides of each segment. Should I paint them white to reflect the light well? Should I paint them red? And should I use some red gel covering (like might be used for stage lights) for the plexi? Or is there another alternative to the gel?

Thanks in advance for your input.


Attached files

[Aaron Maue]

Thoughts, anyone?

Another question too, would I be better off using white LEDs, painting the insides of the segment white and using the red gel paper? Seems like this would be the most similar implementation to stage lighting.

I'm planning to buy the retrofits in the pre-sale, so would like to order the right color.

Thx.

[WhitePlainsNY]

I'd suggest lining the insides with a reflective material (aluminum foil). I'd also frost the plexi. This way you could change the color by just changing the bulb.

[Aaron Maue]

Hadn't thought of either of those. I like it.

[imawlkr2]

As said above I would Line with something reflective. They make an aluminum foil tape for duct work in the HVAC section of any hardware store. Depending on the size of the segment, you could put a red, green, and blue bulb to make a RGB segment to make any color you want.

[paulanator]

Aaron,
that is a really cool project, and I have been thinking about something like that too.

Keep us posted on your progress!

Have you thought about using those RGB 5050 strips that you can cut to length?

[Aaron Maue]

I'll take pictures as I go. And I thought about the RGB strips, but I'm not ready to venture into the world of DMX yet, so I'm going the LOR route. I know I can make that one work.

[whizzr]

I am currently designing a 2' tall LED clock for my display this year that would also be able to be used as a count DOWN timer (such as on New Year's Eve).



My design is to mock traditional 7-segment LEDs, but make them by sticking lengths of LED strip to black Coroplast. The heart of it will be an Atmel ATmega128 Microcontroller, like you find in many Arduino products.



My ultimate design for this includes a carillon consisting of light-up bells that "play" music such as Westminster Chimes on the hour and half-hour.