The Onomatograph

Welcome to the only site on the Web devoted to the Onomatograph. This is a very cheap sound-to-light machine that produces pictures similar to the background image currently mussing with your retinas, and everything about it -- including how to make your own -- is here.

Introduction: A couple of paragraphs that avoid telling you anything about the Onomatograph

Overview: This is more like it

Installation: It's no good unless you do

In Use: It gets better...

Caveats: ... but it can get worse

Theory of Onomatographic Operation 1 -- Physical : This is how

Theory of Onomatographic Operation 2 -- Cultural: This is why

Make Your Own: G'wan!

Future...: My favourite place

Who?: Indeed.

Introduction

Congratulations on acquiring an Onomatograph! This hand-crafted device is designed to give you years of viewing pleasure, as well as being a charmingly ironic statement about the cultural implications of technological consumerism.

Because of the unique construction methods, no two Onomatographs are identical, and you should feel free to experiment with your device's operation to produce results that are most pleasing to you.

Overview

In appearance, the Onomatograph looks much like any monochrome TV set -- which is what it was. In use, though, it transforms audio signals into constantly changing patterns of light that appear as luminous doodles on its screen.

The Onomatograph has the usual controls of any TV set, and in addition four wires for audio input, configured as two twisted pairs. You'll also need a stereo sound system capable of providing around ten watts per channel and having some form of external speaker cabling.

Installation

Connect one of the twisted pairs across the output of one channel of the sound system, in parallel with the speaker. Do the same for the other twisted pair and the other output. Turn on the sound system, but turn the volume down. Plug in and turn on the Onomatograph, and after allowing it to warm up adjust the brightness and contrast controls to give a reasonably bright dot in the centre of the screen, at roughly the same level of brightness as you'd expect to view a TV picture.

Now, turn the volume up on the stereo system. The dot should describe patterns on the screen of the Onomatograph in time to the sound. If it doesn't, or if just draws a single straight line, check the connections.

That's it! Your Onomatograph is now connected and running.

In Use

As you'll quickly discover, almost anything you can change will affect the nature of the patterns. More volume, and the pattern will get bigger: less and it will shrink. It is most sensitive to bass notes, and musical material with a heavy rhythmic content is especially effective. High notes produce ripple effects on the larger, bass-derived patterns, and fiddling with graphic equalisation will change the mix to a great extent.

The balance control is important. It changes the proportion of horizontal to vertical movement in the pattern and can be used to make the image more or less symmetric, according to taste.

The controls on the Onomatograph itself can have surprisingly subtle effects on the nature of the Onomatographic experience. If you tune to a dead channel and turn the contrast up and the brightness down, the random visual noise that would normally produce a picture full of static will produce sparkling modulation on the patterns. Alternatively, if you tune to a TV program -- turn the volume on the Onomatograph up to hear when you've done this -- the TV picture information will produce more regular variations of brightness. Depending on the settings of brightness and contrast and on the TV station's output, this can produce spiral patterns of varying brightness, showers of stars, all manner of strange and intricate effects. Experiment.

Several users have reported increased enjoyment of the Onomatographic experience following their consumption of so-called "mind-altering" substances. The manufacturers pass this observation on without comment.

Caveats

Because the Onomatograph is a simple device, there are some undesirable side-effects of operation that should be understood. Firstly, if the Onomatograph is left on with no audio being fed into it and with the brightness left up a dot will be burned into the centre of the TV tube. This is in no way dangerous, but is an irreversable blemish that will grow with time. Your options are either to make sure this condition never occurs, or to cherish it as part of the Onomatograph aesthetic. We recommend the latter, as the former is hard work.

If you are operating the Onomatograph with an unearthed stereo, there might be a gradual build-up of static on the stereo itself. This will manifest itself as a slight discharge when you touch a metal part of the stereo, such as the aerial. The solution is not to touch a metal part of the stereo, or to take such precautions as you would if working on nylon carpets during cold, dry weather. This effect is not dangerous, but can be alarming if encountered without being prepared.

Use of the Onomatograph will reduce the amount of bass that your speakers will produce, and can otherwise cause a slight degradation in the quality of the audio overall. Most people find this acceptable; those who don't may run the Onomatograph from a separate amplifier fed from the main amplifier. Any cheap and nasty amplifier will suffice. This has other benefits; you can adjust the audio feed to the Onomatograph independently and select the most visually appealing volume, tone and balance settings without affecting the sound.

Finally, please note that the Onomatograph corresponds to no known safety standards, emission regulations or consumer product codes. Caveat lector.

Theories Of Onomatographic Operation 1: Physical

The display device within an Onomatograph is a standard, unmodified TV cathode-ray tube. This works by electrically heating a thin filament within a vacuum, which results in a sea of electrons boiled out of the wire. These electrons are attracted to various high-voltage electrodes within the CRT, which serve to accelerate and focus the electrons into a thin, high-speed beam that is shot towards the face of the tube. When the electrons hit that face, special phosphors glow in response making the end of the beam visible.

In a TV, the beam is further attracted by magnetic fields produced by voltages passed through a set of coils on the CRT's base. One set of coils moves the beam up and down; the other moves it from side to side. By regularly sweeping the beam across the tube while slowly moving it down, the TV picture is built up; the content of the picture is produced by varying the brightness of the dot according to the brightness of each point on the original scene. Boring, huh?

In the Onomatograph, the coils on the base of the tube are fed with voltages from an audio amplifier -- one set of coils from one channel, one set from the other. The dot moves around according to the audio signals from both channels, and the relationship between these signals define the pattern the dot describes. This patterns are known as Lissajous figures, from the name of the French mathematician who first used them to investigate relationships between phases.

A side effect of this simple system is that the display often appears slanted at 45 degrees -- this will result when the music played is largely the same on both channels. The solution to this is either to change your choice of music or to realign the coils within the set so that the 45 degree slant is horizontal or vertical.

Theories of Onomatographic Operation 2: Cultural

Television is the major cultural channel of our age, and has been the dominant medium for half a century. Thus, all aspects of television are imbued with significant semotic content. The televison set itself occupies a place in our experience that is unique in its ubiquity: in many ways, it has replaced the household shrine for intimate communication with the gods that shape our experiental world.

The Onomatograph's significance can be viewed in two ways. First, the device is a perversion of the consumerist ethic. TVs are mass-produced items that are normally seen as impervious to analysis by the untechnical and must be thrown away when their function is done. The Onomatograph is a simple modification of such an item that fundamentally changes its mode of operation and uses the economics of mass-production to produce a cheap device of considerable intrinsic interest.


Second, and more interestingly, the Onomatograph perverts the aesthetic of TV viewing. The patterns it produces are exact visual representations of sound -- hence the name -- but they have in themselves no more information than the original producers of the sounds included for purely audible purposes. The Onomatograph cannot be used to convey visual information designed as such: the Onomatographic experience is pleasant and intellectually stimulating, but cannot carry a message either overtly or covertly. This decoupling from the normal mode of viewing may encourage a more critical appreciation of the components of television per se. Then again, it may not. That's the trouble with cultural theory.

How To Build Your Own Onomatograph

The reader is actively encouraged to promote the production of Onomatographs: no copyright or intellectual property is sought by the manufacturers. Production is simple, fast and very cheap and can be effected with no more than wire cutters and a screwdriver: however, dangerously high voltages are present within TV sets and considerable caution must be exercised. It is not recommended that those completely unfamiliar with basic electronics attempt to produce an Onomatograph. The following instructions should be sufficient to allow a TV repair person, hardware jock or clued-up technician to produce an Onomatograph in a few minutes: others proceed at their own risk.

You will need two monochrome TV sets of similar tube size, tools for opening them up and some wire. A soldering iron is highly recommended. One set will be used as a donor for a part, and will not be usable for anything afterwards. The other set will become the Onomatograph; while it doesn't have to be working completely before the conversion it should at least be capable of displaying a picture, even if it's completely blank.

Safety glasses should be worn while working on the TVs' tubes.

First, make sure both sets are unplugged and haven't been on for a day or so. Those familiar with TV electronics can optionally discharge the EHT circuit using standard procedures -- if you don't know what those are, you're not going to be told here. Don't do it!

Unplug the socket from the base of the donor set's CRT. Then, loosen the deflection coil yoke assembly's compression screw and slide off the assembly -- this is often held in place with some form of adhesive or compressible tape wrapped around the tube's neck, and you may need to loosen this by gently rotating the yoke around the neck until it can be pulled off.

Unsolder or cut the cables that connect the donor yoke to the set. That's it for the donor, which can now be discarded.

In the Onomatograph, repeat the operation but don't disconnect the wires connecting the yoke to the rest of the electronics. The deflection coils are used in the high-voltage generation circuits, and can't be disconnected; instead, find a safe place within the set for the coils to rest making sure that they don't short against anything. Connect the signal input wires to the donor yoke; it should be obvious which of the four connections belong to which of the deflection coils, and as long as you can identify which wires are connected to these it's unimportant exactly how they're connected.

Slide the donor yoke onto the neck of the Onomatograph's tube, and tighten the compression clamp until it's no longer loose to the hand. Don't overdo it.

Thread the signal wire through the back of the set, either tying it to some secure part of the case or knotting it so it can't be pulled out. Reassemble the Onomatograph.

That's it!

Future Ideas

There are many possible modifications to the Onomatograph. A strobe signal could be fed to the brightness circuit to chop the beam, producing a wide variety of patterns; internal amplifiers and microphones could be fitted to produce a self-contained version; experiments could be carried out with colour sets. Computer types might like to program a soft version, using sound sampling software and fast graphics routines; alternatively, old computer monitors can be adapted in exactly the same way as old TV sets. There are too many unused monochrome monitors in the world, and not enough Onomatographs.

Comments and criticisms are welcome at rupert@fly.net

This project was made possible by generous grants of materials, hospitality and kindness from the Brooklyn South 11th Institution for Itinerant Englishmen. Particular thanks are due to Prof. Heather, Dr Dave, St Simi and the Rev Mark.

Brooklyn, 22 March, 1995.

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(oh, in case you're wondering -- the background image is what the Onomatograph looks like in operation. It's not actually a picture of an Onomatograph, just a graphic I stole, shamelessly, from Orbital's web site. I've even removed their logo, thus compounding the crime: nevertheless, this is pretty much precisely what you'll get if you build an Onomatograph and pump P&P Hartnoll's pretty dance mewzik into the device. rg)