A Ho Ho Ho Controller for Christmas

A few years ago, I made this zero-budget Christmas light controller. It was inspired by an old model railroad signal, a small electronic sequencer with three channels and a speed control.

As Tim Allen from the TV show “Home Improvement” would say, “I didn’t fix it, I improved it.”

So, instead of blinking three little LEDs, I added an opto-isolator to the chip (TTL) output so it would be safe to interface with the AC mains, and a solid state relay (SSR) to each channel so it can switch an AC mains load.

Now I can sequence three channels of several hundred watts of Christmas lights. As The Tool Man would say, “Arruuuugh!”

So, when the unit is on, the sequencer lights up HO - HO - HO.

Of course, I could have used some Arduino board and code, but since this was another one of my zero budget electronics projects, I used what I had on hand.

Here are some more pictures of this project. Electronics people will understand this. Let me know if you want more details, or have any comments.

Here is the unit under test. . . 

Here is a closer view of the circuitry. At the bottom left is the power supply (DC-DC buck converter to 5VDC, using a three terminal regulator. Above and to the far left is the model railroad signal light. The light-colored board just below that holds the opto-isolators connected to the TTL output. The three yellow packages are solid state relays (SSR), taking the logic signals and switching them for the AC mains voltage. The outputs from the SSRs go to extension cords, which then connect to each "HO" light. 

Tags
#Electronics, #Maker, #MakerFaire, #DIY, #Christmas, #Decor, #Winter

About Wayne Yoshida