Technical Information about Dirknerkle's Lights 2009

Helpful Terminology to Know

Controller - an electronic device that decodes a computer signal and translates it into a command to set the light intensities (brightness) of lights connected to various channel circuits. Some controllers have only 8 or fewer channels they can manage; others have 16, 24, 32, 64 or 96 individual channel circuits they can control. A controller usually does not need very much electricity to run -- some can operate on as little as three AA batteries. However, some controllers are designed to be plugged into AC power or external power supplies. A more recent development in the hobby is the use of E1.31 controllers. This means "ethernet" which opens the door for some rather incredible communication speeds and channel potential. Digital controllers in the tens of thousands of channels are now a possibility, and at affordable prices, too. These high channel counts are necessary for the control of high definition RGB displays that can display pictures and even motion video. Not everyone has an interest in doing that (or the interest in paying for it!) but it's available.
Click photos to enlarge them
Dimming - the ability to vary the intensity (brightness) of lights connected to a channel circuit. Same as being able to fade lights down to off or raising their brightness levels up to full brightness.
SSR - "Solid state relay" - this is essentially a small electronic on/off switch. It is normally connected to two different circuits: high voltage power for the lights and low voltage control power from the computer. When the computer sends a small signal to the SSR, the SSR "turns on" and allows electricity to flow to the lights that are connected to it. An SSR is generally quite compact and can be placed anywhere or even built into a display. We typically use 4-channel SSRs where a single unit can power the lights for up to four of the controlled circuits. However, we also designed single-channel SSRs and built them into wreaths or other 1-channel display units. In essence, an SSR is the final link in the chain that actually allows the electricity to flow into the lights and make them bright, or cut off the flow of electricity and turn them off. Because an SSR is connected directly to powerful electrical current, they must be handled very carefully and never when the power is turned on because an electrical shock can be fatal. We invented the first "selectable channel" SSR which allows choosing which of 4 channels a circuit responds to out in the field instead of only at the controller. This extends the current-carrying capacity of a single channel to upwards of 12 strings of lights whereas normally, a single channel is thought to control only up to about 3 strings. We also invented the first 24-channel SSR whereas most are only 4 channels. We like to go big!

4-channel channel-selectable SSR

SSR in waterproof box, attached to a light frame
Cat5 - common, inexpensive computer wire that is used to connect computers on a network. This hobby uses a lot of this inexpensive cable because it contains four pairs of wires -- enough for up to four channel circuits per cable.

Main controller box located in garage
Daisy chain - the ability to connect one electronic item to the next, then to the next, to the next, etc. much like you might use 3 or 4 extension cords to create a cord long enough to plug in a light across the room from an electrical outlet -- one cord into the next, into the next, etc. You can do this with controllers, too -- daisychaining three 24-channels together essentially creates a 72-channel controller.
Mega tree - a simulated "tree" made up of strings of lights attached to a frame to emulate the conical shape of a Christmas tree. Some mega trees truly are "mega" and are 20, 30, and up to 50 feet tall or more. Mine was 12 feet tall and used 24 channels (strings) of lights for 2400 lights on the whole tree. The more lights you put on the mega tree, the more spectacular it looks; some have 96 or more channels and many tens of thousands of lights. A mega tree can be "animated" which means it can be made to appear to spin, change colors, etc. simply by rapidly changing which strings of lights are on and which are off. Most mega trees have a topper of some kind; mine was a simple star made out of plywood and painted black with rope light attached to the outside shape.

2009 mega tree with rope light star
Mini tree - as a mega tree is large, a mini tree is just the opposite. It's a short, 2 to 4 foot tall frame wrapped with lights that simulates a small pine tree when lit. These add splashes of color and animation in other parts of the display. A mini tree typically has anywhere from 300-1000 lights; ours have about 600 when fully lit. We also have midi trees, which are not suprizingly, sized in between a mini and mega tree.
two mini trees

Equipment used in our Display

Olsen 595 controller - this provides simple on/off control of up to 64 individual channels. A channel can be connected to a single light, or pair of lights, a whole string of lights or even multiple strings of lights (usually limited to 3 or fewer per channel because of electrical limitations). While it's a great performer, it's old technology and hardly anyone uses them anymore. I still do as a display board that monitors my actual show while it's running. It's nice to have in the lab.

Two Olsen 595
Ren-C converter - this is a device that converts the computer's serial signal into one that the Olsen 595 can use, and it adds the capability to do gradual light dimming on every channel instead of only on/off control. A channel can be set anywhere between 0% - 100% intensity. Being able to gradually control the light intensity up or down provides very smooth transitions between lighting effects. A Ren-C is also old technology and rarely used anymore.

Renard SS24 controller - a self-contained unit that has the built-in electronics of both a controller and 24 SSRs, as well as the capability to perform dimming. Renard is sort of a "brand name" in this case. It was developed by a fellow named Phil Short and if you're the inventor, I guess you can call it whatever you want! The SS model comes in three channel counts: 8 channels, 16 channels and 24 channels and was a collaborative product created by Wayne James and Phil Short. It's still manufactured today and thousands of them are in use. It's become the "standard" of the DIY lighting hobby. I have other Renard controllers of my own design that I use now, but I still use the SS24, too. I also use Renard-Plus controllers that are designed by one of my good friends. Phil did an amazing thing when he created the Renard concept -- it just works.

SS24 in
waterproof case
Ren-W wireless adapter - this provides a way to control one or more Renard SS controllers simultaneously by transmitting the computer control signal wirelessly to other Ren-W units that are serving as receivers. Converts a normal "hard wired" Renard controller into a wireless controller that may be placed anywhere in the yard within about 1200 feet of the transmitter, and thus eliminate the cat5 wire. Yours truly invented this adapter, and it saw service for the first time in my show in 2009. It worked great! I used a transmitter Ren-W in my garage to send the signal out to the mega tree, which had a Ren-W receiver/transmitter installed on the SS24 that controlled the mega tree. That unit then forwarded the signals to other wireless units also in the yard that were controlling eight mini-trees. In 2010 I started selling the Ren-W circuitboards to other DIY'ers so they can join in this wireless fun. Wireless control opens the door for incredible features and functions that are quite difficult to achieve otherwise. It also can eliminate a LOT of wiring! Since that first prototype in 2009, the wireless control concept has expanded quite a lot with "snap-in" boards that can not only use the same XBee radios that the Ren-W uses, but other modules such as the nRFl2401 and more recently, the ESP8266, which provides full wi-fi capability and control flexibility that was nothing but a dream back in 2009.

SSRs - I used a variety of SSRs of my own design in 2009 and I still use some of the same ones! They're very durable. Most were 4-channel units to control multiple strings of colored lights around windows but several single-channel selectable daisy chain SSRs were used to eliminate extra cat5 cabling runs from the controller box in the garage.

1-channel SSR
Displays - many of our displays use frames made out of common PVC pipe -- exactly the same pipe that is used for home plumbing because it's inexpensive, easy to form into shapes and plentiful. Normally PVC pipe comes in white, gray or black, and after building a frame with it we paint it either dark green or black so it's not as visible at night. Light strings are attached to the frames using zip or cable ties. We buy these by the thousand because it's not uncommon to use a hundred or more on a single frame. Mounting the lights on frames makes it easier and faster to hang the lights. The frames are securely attached to the house using more zip ties threaded through screw-eyes mounted at various locations into the side of the house, or a tree, etc.

Arch frame
Wire. Lots of it. In 2009 I used about 2500 feet of cat5 network wire alone but wireless has reduced that to almost none. Add do a few hundred feed of extension cables, plugs, connectors, tape, heat shrink tape (to keep moisture out), and you get the idea that this hobby requires its own electrical infrastructure. To some degree, where cables can be safely routed is a concern as displays are designed and placed in the yard or on the house.  

Computer & Software

The computer we use to design the lighting sequences and run the show is a Dell GX-280, which is a 2.8ghz Pentium-4, dual-core unit with 2gb RAM, Windows XP-SP3, an 80gb hard disk drive, with standard serial, parallel, video, and a handful of USB ports. In short, it's a basic PC that one could have bought from the Dell web site for about $750 in 2005. We bought it as a refurbished unit from a local used-computer company for about $150 in early 2009. Because this computer isn't connected to the Internet or even our home network, there is no anti-virus or firewall software installed and running on it. Nor are word processors or any computer games -- it's really a stripped-down computer that's dedicated only to our light display. Because it has so little overhead to manage, it runs so fast and performs so well that it's just a joy to use; it's one of the fastest computers I own even though I have many others with faster processor chips and more memory that are bogged down with lots of anti-virus and other application software. It still runs like a top and the only time it's used is to control the show, so we expect it to last many, many years yet. Just in case, we have a backup Dell that we can power up at a moment's notice and run the show with that. And for possibly a little overkill, we have a Raspberry Pi computer set up that can run it as well. We like redundancy.

The software we use to operate our display is a popular software product called Vixen ( Vixen is just a wonderful program designed by a fellow who goes by the initials "KC." He's another Christmas light enthusiast who's made his software available to the public without charge -- which is amazing in and of itself. Vixen looks and acts a lot like a spreadsheet with rows of channels and vertical columns marking periods of time measured in 50-millisecond blocks (20 per second). When a cell is turned "on" at a certain period of time, the channel that cell is assigned to turns on at the same time. So as the timeline bar scans horizontally from left to right in real-time, it scans all available channels for cells that are colored-in and lights those channels; a blank cell means the light is off. Cell values are assigned in terms of a percentage where 100% is "full on" while 0% is completely off. Anywhere in between represents a dimmed value so that a cell that's set to 50% intensity will turn on the light for that cell's channel at 50% intensity, too. Vixen has many editing and other functions and is a rather full-featured, creative and efficient piece of software. In the picture above, you'll see a screen sample of our "Wizards in Winter" sequence which shows various channel names at the far left, a time bar across the middle, and colored-in pixels that turn lights on or off. We use version 2.1.4 of the software which is a really solid, stable version. A 2.5 version was created but it had lots of problems and was discontinued.

Since 2009, a consortium of other hobbyists have developed Vixen 3 and it's quite popular, and a good friend created a mid-version between 2 and 3 called Vixen Plus. A fellow named Joe Hinkle created HLS, Hinkle's Light Sequencer and many use that powerful tool. Another group of users have created Nutcracker (a graphical pattern generator) and merged it with a program named XLights, and that's tremendously powerful and capable. Still, another group created the Falcon Player which runs on a Raspberry Pi and it's become a fantastic player tool that can play sequences from all the above mentioned software tools --  while running on the very inexpensive ($30) Raspberry Pi computer at the same time! This hobby reaches into some very broad fields of expertise!
How Does It Work?  
  1. Vixen software running on the computer located in the basement sends its commands out the serial port of the computer.
  2. The serial port is connected to the Ren-W transmitter which is mounted outside on the side of the house.
  3. The Ren-W transmits the control signals out to all controllers.
  4. Each controller has a "channel address" and responds only to the channels it's assigned to use.
  5. The controller responds to the controls, either turning on or turning off the power to the lights. "Dimming" is essentially the same: if the light is on only 50% of the time, it seems only 50% as bright to the eye.

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