H. P. Friedrichs (AC7ZL) Homepage





Yard Light 






Steam Punk Telegraph Lights:

Making Your Own Landscape Lighting


It's no secret that I love garage sales. Of course, it doesn't hurt that I have an affection for all things antique, particularly artifacts of old technology, and that every once in a while, a person like myself can stumble upon a great deal.

On one occasion, as I stepped closer to examine the merchandise spread across the top of an old card table, my foot hit a cardboard box sitting beneath it. I dropped to one knee to examine its contents. The lady whose garage sale I was visiting noted my interest in the box.

"Those are old, glass, telegraph thingies," she said, authoritatively.

Sure enough, when I opened the lid of the box, I discovered a sizeable collection of antique telegraph insulators. I could see two of the brown porcelain types, a clear glass one, and oodles of beautiful green glass insulators in several styles. In total, there had to be at least two dozen there, maybe more.

A century-old glass telegraph insulator


"What are you asking for these?"

"Gimme five bucks and you can have the box."          

"Sold," I said, as I slapped five Washingtons into her palm.

Later in the evening, I marveled over my newfound treasures, pondering where they were made, where they had been used, and what sorts of messages might have been conveyed over the wires they had once supported. There is something about antique glass that stimulates the packrat section of most people's brains. Let's face it, sparkly things are attractive. Or, maybe it's the crystal-ball-like optical quality of thick, bubbly glass.  You can't help but get the feeling that items like these were made for  "lookin' through." In a darkened room, I placed a flashlight beneath each of the insulators and marveled at the pleasant glow.

And then, despite my enthusiasm, the insulators were returned to their box. Eventually, I decided to leave the snow, ice, road salt, and rusty fenders of the mid-west and make my way out to Arizona. I moved numerous times during that journey. Along the way, some of my greatest treasures were broken, lost, or even stolen, but the box of insulators followed me wherever I went. Patiently they waited, safe in their cardboard sarcophagus, mummified in wrappings of protective newspaper, their final resting place- - the attic of my home in Tucson.

Home Improvements

Picture now the passage of twenty years or more, from the garage sale at the beginning of this story to today. If this was a "B" movie from the nineteen-fifties, you'd be seeing clocks spinning and calendar pages flying off the wall-- in other words, a long time had elapsed. This brings me to a point about a year ago, when my wife and I decided to improve the look of our front yard. We arranged for the installation of a low masonry dividing wall, and the installation of brick pavers so as to create a large front patio area. The result was a beautiful and inviting entranceway to the house. Still, we felt that something was missing. Safety and aesthetics demanded some additional lighting.

I purchased two gas-lantern-like 120-volt fixtures for the brick wall, installed them and wired things up. In the interests of saving energy, we fitted the fixtures with a couple of commercially-made Edison-based LED lamps. The amount of illumination was perfect and the effect was nice, casting a cheerful glow through the opening in the wall, but it also underscored the fact that the rest of the pavement was still pitch black. We needed some more yard lighting.

Looking At The Options

My next step was a trip to a nearby home-improvement center to look at yard lighting fixtures, wiring, and power supplies. This preliminary research proved to be very useful, if for no other reason than it helped me identify everything about commercially-made yard lighting that I dislike.

For instance, to my eye, all the fixtures I saw could be sorted into one of two categories– expensive, or utter crap. The crap fixtures were those that were cheap-looking, flimsily-made, or were otherwise fabricated in such a way that they could not possibly last in the heat and intense ultraviolet light pervasive in the Arizona desert. On the other hand, anything that was half-way decent was also expensive. The cheapest fixture that my engineering sensibilities could tolerate was on the order of $30 apiece. Since we anticipated needing about 10 fixtures, this meant I would be on the hook for at least $300.

Most of the fixtures I saw made use of incandescent lamps. Now, I can't say I dislike the quality of the light they produce, but incandescents are power-hungry and inefficient. Depending upon the fixture and what kind of bulb is installed in it, you can expect power consumption in the range of 4 watts to 15, 25, 30 or even more, per fixture! Ten 20-watt bulbs, for example, consume 200 watts, which is a lot of energy to be burning all night long. Needless to say, I was not very happy at the potential operating costs of this hardware.

Lamps are powered by transformers, specially designed and sold for landscape lighting. The transformers convert 120 volts AC to approximately 12 volts AC. Some are fitted with a mechanical timer that can switch the transformer on and off at preset times. These are not cheap, and their cost is proportional to the amount of the power the transformer is capable of delivering. The transformer should actually be sized to deliver more than the expected amount of lamp load, at least by a factor of 1.1. Then, if there is any possibility that lamps might be added in the future, you'll want some additional reserve capacity. In my case, the appropriate transformer would have added another $150 to $200 to the project cost.

Next, you need wire. Direct-burial, low voltage lighting cable comes in different gauges. Appropriate gauges are selected on the basis of the number of fixtures powered by the wire run, and how long the installed wire run will be. Copper has become horribly expensive in recent years, and this expense is reflected in any wire you purchase. The heavier the gauge, the more copper is used in the wire,  hence the more expensive it is. Power-hungry fixtures with incandescent lamps draw a lot of power, which recommends the use of heavier and more expensive wire.

A typical installation involves placing the transformer in a sheltered area near an outlet. The low-voltage wire is connected to the transformer, and then buried in a shallow trench, following a path commensurate with the placement of the light fixtures. How are the fixtures connected to the feed cable? Our home improvement center sells special plastic tap clips for about $2.60 each. The clips feature little metal teeth that "bite" through the insulation of the feeder cable when the clip is attached to the feeder. Two free wires dangle from the clip. These wires are connected to the corresponding wires that dangle out of each light fixture, and the connections are secured with wire nuts.

I'll spare you my full list of objections to these clips, not the least of which is the additional $26 they would add to my projected costs. Just how such clips and the connections they make could possibly be robust and water-tight escapes me. I would envision electrical failure in short order.

I looked at my notebook, the figures I had scribbled, and the comments I'd made in the margins. No, doing things the conventional way was going to be way too expensive. Even if I decided to spend the money, I was not convinced that the outcome was something that I would be happy with, anyway.

"Steampunk" Yard Lights, Anyone?

"Steampunk" is a fantasy genre that takes modern technologies and places them into historical settings. Technologies of the present are fancifully expressed in terms of old, period materials and processes. Thus, an hypothetical steampunk computer might have all the capabilities of the computer I am composing this article on, yet instead of plastic and sheet metal, it is more likely to be housed in a Victorian-style mahogany box with brass corners, hinges, and hardware. While my computer contains silicon chips, the steampunk equivalent would be filled with polished brass gears and clockworks. The essence of the steampunk genre, then, is the fusion of the new with the classic.

I really don't know if I qualify as a steam "punk" myself, but I surely have steampunk tendencies. It is the only way that I can explain why, after twenty-plus years, my telegraph insulators should suddenly return to the forefront of my mind.  I remembered how they looked when illuminated with a flashlight, and it occurred to me that they would provide the ideal housing on which to base the design for some home-grown yard lamps. Needless to say, I soon searched my attic and recovered them, pleased to find them in precisely the condition that I left them.

Design Objectives

Insulators in hand, I began to contemplate how i might turn these artifacts into useable yard lights. There is a lot to be said for the novelty of this idea, and for the rights to claim one-of-a-kind status for the finished product. However, it was my expectation that whatever I came up with would also be less expensive, yet better than the commercial alternatives I had already explored. To assure that this exercise was worth the trouble, I established a set of design criteria that I was committed to meet.

First, it was my expectation that the design be robust. I wanted something that I could reasonably expect to last 10 years or more in the Arizona heat, the winter cold, and the monsoon rains. Fortunately, century-old telegraph insulators have an established track record for long life, despite exposure to the elements. Short of smashing them, they last almost forever.

Second, I expected the design to be inexpensive, both in terms of material costs and labor. I placed my focus on the use of as many common, off-the-shelf parts and materials as possible, and chose them to minimize fabrication efforts.  

Third, I expected these fixtures to operate with low power. In this context, even 4-watt light bulbs represent gross overkill. I wanted something bright that would run cool and lean, so I wouldn't have to fret over the impact of this yard improvement on my electric bill.

At the same time, I am much annoyed by the flicker produced by most alternative light sources, including fluorescent lamps and LEDs powered by AC current. This flicker, which I perceive at the periphery of my vision, is an artifact of the alternating current itself. To me, it is the optical equivalent of fingernails raked across a chalkboard. So, my fourth criterion was this: Whatever I used to light my lamps, no flicker would be tolerated.

Fifth, I wanted to be able to wire my lights without the use of those connector clips that I lambasted earlier. I wanted to avoid any electrical connection being made below ground level, or where it be easily exposed to moisture and dirt.

Finally, I wanted the design to be simple enough to guarantee that I would be able to repair and maintain the fixtures indefinitely.

Starting with one of my insulators, I  developed my ideas in the form of a prototype or two, gauging the results against my design criteria. I made a couple of mistakes along the way, and revised my material list when things didn't work out quite as I had intended.

The end result meets my requirements and is easily replicated, but the usual disclaimers apply. I can show you what I've done, and I can encourage you to try building your own lamps, but please bear this in mind: You assume full responsibility for your health, safety, and compliance with any local rules or regulations. Blow something up... well, you own that. Got it? Now let's build some lamps.

Building The Lamp Body

Construction of each of my lamps starts with a glass insulator. I recovered mine from storage, and my wife soaked them in warm, soapy water to remove dust and grime. In my design, the insulator comprises the lamp's lens and the bulk of its body.

The next step is to obtain a 1 and 1/2-inch ABS plastic female thread adapter. Externally, this looks like a pipe coupler, but the interior of one end is threaded. This fitting  comprises the rest of the lamp body.

An ABS threaded adapter is used to fashion the lamp body


The glass at the bottom of the insulator is flared, and I found through experimentation that a 1 and 1/2-inch fitting will fit nicely into the underside of the insulator. Fabricating a complete lamp body, then, is simply a matter of joining these two pieces together.

Bonding the adapter to the glass is accomplished by applying a heavy bead of clear silicone adhesive to the inside of the insulator's skirt, inserting the ABS pipe fitting, and letting the whole thing set. Note that ABS is not tolerant to UV exposure, so before assembly, I applied a couple coats of spray paint to the adapter to protect it.

Building The Lamp Base

With the lamp body complete, it's time to fashion the base of the lamp. You'll need 1 and 1/2-inch ABS threaded pipe plug, a 3/4-inch EMT conduit connector, the matching nut,  and a 3/4-inch to 1-inch knockout adapter. The knockout adapter really amounts to nothing more than a large washer.


The pipe plug and EMT coupler (click on images to enlarge them)


A threaded plastic pipe plug features a cubical protrusion that extends from its face. In normal use, this is the thing you'd engage with a wrench to drive the plug into another fitting. For our purposes, it must be removed. This is easily accomplished with a hacksaw. Then, the face of the plug must be drilled to produce a hole large enough to accept the threads of the EMT conduit connector.

I discovered that, using a step-drill, it's possible to drill the required hole and mill away the cubical plastic protrusion in a single step, saving a lot of time and effort. All that was needed to finish the job was the application of a utility knife to trim away any excess plastic.  


Modifying the pipe plug (click on images to enlarge them)


To assemble the lamp's base, you start with the EMT connector, stack on one of the knockout adapters (washer), and then insert the EMT connector's threads into the hole you drilled through the pipe plug. Finish the assembly by installing the EMT connector nut, and tighten it snugly. It's a good idea to give the completed assembly a shot of spray paint, but avoid getting any paint on the plastic threads.

The completed lamp base screws into the bottom of the lamp body.


The finished lamp base (click on images to enlarge them)


Building The Stem

The stem of my lamp is composed of 3/4-inch EMT galvanized conduit. This stuff is strong, dirt cheap, and corrosion resistant.

Fabricating a lamp stem is largely a matter of cutting the conduit to the desired length. Given the soil conditions around here, I have found that the best length of a lamp stem is twice the height at which the installed lamp will stand. In other words, I like as much conduit below the ground as above it. This keeps the fixtures upright despite heavy wind, heavy rain, or the occasional impact from a garden hose or a lawn rake. You can cut conduit with a hacksaw, but I prefer to use a pipe cutter, as it does a neater job.

When in use, the wires that power the lamp will travel through the interior of the stem up and into the lamp body. It's not practical to have the wire enter at the bottom of the stem, because any subsequent effort to drive the stem into the earth will cause the wires to be chopped off, as though in a guillotine. I prefer to drill an access hole in the side of the stem, located an inch or two below (what will become) ground level. A 1/2-inch hole will easily accommodate wire up to 12-gauge, and provides enough relief that pushing the wire up and into the lamp is no problem.


Lamp stem details (click on images to enlarge them)


Note that cutting and drilling holes in steel always leaves sharp edges. I used a Dremel (tm) tool with a grinding bit to dull all of the edges on the lamp stems I produced.  

Stems don't have to be painted, but I wanted a uniform appearance among the parts of my lamp. A few blasts with a can of spray paint is all it takes.

Building The Electronics

Early on, I decided that I was going to use white LED's to light my lamps. The prior year, I had accidentally purchased a string of LED Christmas lights fashioned in the "icicle-style" , when what I thought I was buying was the classic "straight-line" type. That made this particular string an oddball among my Christmas decorations, and a perfect victim from which to cannibalize the LEDs I would need.  

Harvesting LEDs in this fashion cost me the equivalent of 15 cents per LED. Happily, white LEDs are available everywhere, and prices continue to fall as production ramps ever-skyward. Among the best deals on LEDs I've seen are those offered by certain Hong Kong dealers on that you-know-who auction web site.

Each lamp fixture in my design contains six LEDs, arranged to point radially in 60-degree increments, so as to distribute their light. Unlike incandescent bulbs, LED's are somewhat picky about the quantity and quality of the power that drives them, so it is necessary to include some additional circuitry to make everything work properly.

For starters, LED's are direct-current devices, while standard landscape transformers deliver alternating current. To compensate for this difference, my design includes a full-wave rectifier to convert AC to DC. The DC is filtered by an electrolytic capacitor which serves the dual purpose of suppressing voltage spikes while eliminating the annoying light flicker that I railed about earlier. Finally, my circuit includes a couple of 330-ohm resistors to limit the current flowing through the LEDs to a safe level. You can see the schematic for my lamp circuitry here.

The lamp schematic (click on image to enlarge)


Rectifier bridges and capacitors can be purchased from any electronic supply house, or even salvaged from electronic scrap. I found mine online at an auction site. My rectifier bridges are type W02M, good for 200 volts and 1.5 amperes– ten or more times the levels they will see in actual use. My capacitors are 220-microfarad, 25-volt electrolytics. Their voltage rating is roughly twice what they should ever see while in use, and being industrial-quality, they're rated for application in temperatures from -40 degrees C to 105 degrees C.

Since the lamp circuitry is so simple, there are several techniques that can be employed to wire the parts together.  I decided to fabricate primitive circuit boards.

For each lamp, I began with piece of single-sided copper-clad fiberglass board, measuring roughly 3 and 3/8 inches long by 7/8 inches wide.  Using a small ball rasp and my Dremel (tm) tool, I divided the copper on the board into little squares or pads to which I soldered the various components. Some parts were installed on the side of the board with the pads. Others parts were installed on the opposite side of the board, making it necessary to drill tiny holes through which component leads could be threaded.


Hand-made circuit boards (click on images to enlarge them)


One of the neatest features of my boards is the built-in terminal block. Using the Dremel tool, I established two large copper pads where power was to enter and leave the circuit board. I drilled four holes through the board (two through each pad), sized to pass 6-32 screws. Then, I soldered 6-32 nuts to the pads. The screws thread right through the board, into the nuts, and form the terminals by which wire can be connected to the lamp circuitry. Four screws allows a power cable to come in, and another one to leave, in a daisy-chain fashion.

This approach to wiring the lamps eliminates the need for the expensive connector clips I talked about earlier. By locating the connections within the lamp housing, they are protected from exposure to dirt and moisture.                

Installing The Lamps

Installation is pretty much what you'd expect. My wife made a visual survey of the area and determined where she wanted the lamps to be. She marked the desired locations with rocks.

At each location, I drove a lamp stem into the ground. The earth in this part of the country contains lots of a substance called caliche, which in many cases is as hard as concrete. Rather than pound the stems into the ground with a hammer, which would have deformed their tops and made installation of the lamp fixtures impossible, I opted for a more subtle approach. Temporarily, I coupled a garden hose to the top of each stem and turned the water on. The jet of water emerging from the bottom of the stem cuts through caliche like a knife through butter. I was able to push the stems into the ground with nothing more than the pressure applied by my hands.

With the stems in place, I dug a shallow trench that followed the chain of lamps. Using 16-gauge low-voltage lighting cable, I started at the transformer, and ran cable to the first lamp stem. Gathering some excess, I folded the cable so as to double it, and then pushed the doubled section into the hole in the stem. I worked the folded section up and out the top of the stem, leaving a five-inch loop. The free end of the cable was then extended to the next lamp stem, where the process was repeated.

When you're finished, the cable runs up into, and then back out of each stem, and extends to the next lamp in the chain.  I installed a lamp base on each stem, using the set screw on the EMT connector to lock the lamp base to the stem.

Next, using wire cutters, I severed the wire loop protruding from the base of each lamp, and stripped back some of the insulation. To each lamp base, I installed a circuit board using the screws on the board to attach the wires. If you look closely at the photo, you'll notice that I added some washers to each screw to help clamp the wires more securely.

All that's left to do is to take the lamp bodies (the insulator and the attached adapter) and screw them onto their respective lamp bases.


Wiring up the lamps (click images to enlarge them)


The finished lamp, installed


Results And Comments

What does one get for the trouble of building their own yard lights? I'll let the following photographs speak for themselves, but allow me some commentary.

My wife and I are extremely pleased with the finished results. The light produced by my lamps is plenty bright, without being harsh or blinding. The light is tinted by the green in the insulator glass, which is visually appealing when played across the prickly pear cacti, agaves, and saguaros that make up the surrounding landscaping.

Lamps lit at dusk


My lamps were relatively inexpensive. Given what I had on hand and what I could score as surplus online, the fixtures came in at around six dollars apiece. Because of the reduced power consumption associated with LEDs, I was able to use the smaller 16-gauge wire, and a small, light-duty transformer. That amounted to a 50% savings over what I would have spent otherwise.


(click on images to enlarge them)


Personally, I cringe at projects that require bona fid antiques to be destroyed in order to fabricate whatever their author is advocating. An important aspect of the design of my lamps is the non-destructive manner in which the antique insulators are deployed. If, for some reason, I ever decide to retired them from yard service, they can be separated and recovered from the rest of the lamp fixture with a utility knife, with no harm done.


The ABS plastic lamp body is an acceptable compromise for a cost-conscious application. My first choice, however, was to use copper fittings, which are superior in terms of wear-and-tear and in overall appearance. Left unpainted, they assume a warm brown patina over time. The only reason I went with ABS is that it costs 1/10th what the copper equivalents cost, but I'll be honest, my preference is for the copper.


Telegraph insulators are collectable items. Supply has dwindled and demand has increased, so they've become expensive over the years. Now, the odds of someone finding a big box of insulators at a yard sale is pretty slim. However, My experience with this project has been encouraging enough that I have begun exploring the application of this idea to other materials. In thrift shops, dollar stores, and garage sales, I have seen dozens of beautiful glass votive candle holders, tumblers, and liquor glasses that, inverted, might form the basis for a new family of lamps. As we speak, I am experimenting with a small, heavy, drinking glass that features a diamond-shaped "cut glass" pattern in its walls. When lit from within, the affect is dazzling and the light is well distributed. This particular American-made glass is a dollar apiece, and can be purchased online, new, by the caseful.

An inviting entrance


I am also experimenting with some ideas to make the lamp circuitry a little more flexible. While the present circuit is cheap and seems to work well, it can't be used under all circumstances without some minor modification. Different LED's or a different transformer may require adjustments to the value of the current-limiting resistors. Run your LEDs with the current too high, and you'll burn them up. I've planned a simple circuit that will assure current limiting over a wide range of input voltage values. I am also toying around with the idea of producing and selling circuit boards or circuit board kits to allow people to create their own lamps. If I get enough feedback to justify the seed costs, I will probably go ahead with this and make them available through my web site.

The next level to take this would be microprocessor control... perhaps a low-pin-count PIC chip or something similar, contained within each fixture. With intelligence in the lamp itself, you can easily modulate light intensity and color, and even have multiple lamps communicate or coordinate with each other.

The bottom line is this: Next time you find yourself in need of some low-voltage yard lighting, exercise some creativity and ingenuity, and make the lamp fixtures you need by yourself.


(revised 05/03/09)

(revised 07/26/09)