The Supreme Reality's Long and (Coil) Winding Theremin Project.


audiorecording@thesupremereality.org
























WARNING: Extremely Long!!!

All right, I promised I'd give it to you, so here goes, hope you'll find some entertainment in reading:

Once upon a time (early 2001?), after discovering a mutual interest in tinkering with electronic things, my co-worker Bill Wray and I decided to build a theremin. Bill is an electrical engineer who I work with at Dolby Laboratories; I'm an editor (with limited electronic skills and a perverse need to solder). Bill spent his youth building everything from radios to a TV set as a present for his parents, and is still active refurbishing old radios, particularly Hallicrafters shortwaves and the like.

The reason we decided to build a theremin together is, I believe, based on a prior conversation we'd had about theremins. (He'd come to appreciate them through the radio connection and the fact that he'd seen or heard a performance of an Olivier Messiaen piece that included Ondes Martenot, which inevitably led him to the theremin; I knew about them because for years I've had this compulsion to know about all fringe music-related stuff.) I think our kickoff conversation went something like:

Bill: "Hey, I thought it would be fun to make something. Do you want to build a theremin?"

Me: "Sure, let's do it."

Then of course, came the decisions of how we were going to go about it. In his opinion: "Kits are boring." "Has to be tube; has to be capable of outputting the same waveform as an RCA or it's not worth doing. It should have its own tube power amp. See what you can find."

I hunted around the Internet, found the now-defunct Maxie's Pages, and printed out a few schematics. Bill looked them over with a friend at work, and found that a good deal of the tube designs were incomplete, had obvious mistakes, and so on. We looked at the 1954 Moog, and I also found someone who had a copy of the April 1955 issue of Popular Electronics, which featured a DIY theremin cover story. If I recall, these all had a particular tube or some other part that was going to be hard to find, way expensive, or both. Being a vintage radio collector/restorer, Bill already had plenty of esoteric NOS tubes and bakelite sockets, and several sources for whatever oddball components one might need. So we're talking about a pretty high geek factor already. There's no way I would pursue anything he even flinched at.

We found one design that had obtainable tubes, but it also had coils. Bill thought we might get lucky and find the smaller oscillator coils in a TV repair shop; he said old tube televisions had something in the ballpark that we might be able to make work. I went to a couple of the most ancient repair shops I could find-well, more like the only two that were still in business in Oakland, California-and…nothing. He went to a few places in the South San Francisco and San Jose areas with the same results.

At which point we simply gave up.

Fast forward to December 2002. My wife and I decided to up and move to Portland, Oregon, and had arrived eight months prior. I'd been looking on a local classifieds-type newsgroup and had bought a couple things from Mark Keppinger, a Portlander who regularly scrounged up the most bizarre and amusing assortment of stuff and sold it for next to nothing. Fifty hazardous waste outfits? Decrepit bumper cars? A beautician's dummy head, complete with hair for practice purposes? These are all real examples, and just par for the course with Mark (at least back then).

On a day in late December, he posted an off-topic, non-for-sale message to the group. He'd been working on a new design of a tube theremin in secret and was finally ready to unveil it. Of course, I was very curious about the thing, but what I especially wanted to know was what he did about the coils, so I fired off an email describing what we had tried to do and asking about it. As most people with an interest have now been made aware, the answer was that he made them from scratch. From the phenolic tubes that are used for model rockets. With a special winder of his design, which, if you ever get a chance to see it, is hilarious. It's made out of sewing machine parts bolted to a piece of plywood with a spring-loaded tube holder and a counter that advances once per revolution. It might as well have some twine and chewing gum, but it works damn well.

He was willing and even excited to answer my questions, maybe because he was coming off the high of finishing it. In any case, he offered to let me use his schematics and winder if I wanted to pursue the project once again. (He said he would offer the schematic freely to anyone who wanted it. Whether that's still the case I don't know but I bet it is. He seems very "open source.") He gave me all the information on where he got the cardboard tubes; on cardboard tube diameter, turns, taps, wire gauge, and so on; on where to get transformers. He even had chassis from one of his prototypes that he gave me. Unbelievably nice, and of course that saved a ton of time since most of the holes were already punched. He let me have at a disassembled unit so I could turn the chassis upside down and take pictures. From this we were able to blow up prints, tape them together, and use them as a wiring diagram.

So, Bill and I were off and running. The only bug was that we no longer lived in the same state. But I had essentially returned doing my old job, only now as a freelancer. In this status I went back to the Bay Area to go to the office every couple months anyway, and we could work on it in the office after work and on weekends. So that's what we did…for the next two years.

We made a parts list and bought all the big stuff. We purchased most of it through Radio Daze. For the little stuff, the smaller capacitors and resistors and whatnot, we could scrounge it from the tech room at Dolby. Dolby is a company that encourages this behavior (within limits of course) on the grounds that it's ultimately making people better at what they do. Plus the little stuff is cheap, but in any event, that was very handy.

Along the way, questions naturally arose, and with our elongated timeline I would just send an email to Mark, wait until he could answer, and deal with it on the next trip. The wiring of the chassis underside was somewhat straightforward but I'm hardly an expert. In a given evening, I'd solder everything I could figure out from the schematic, the tube sockets and the jacks and switches, and then Bill would do the harder stuff and answer my schematic questions from my previous round. For checks and balances, I'd check Bill's work and he'd check mine.

When I was back in Portland and had time to deal with it, I'd try to get other things checked off the list. For instance, the mounts that raise the oscillator coils off the chassis have to be nonconductive and a specific height, with holes drilled at a certain spacing for the nonconductive bolts to attach the whole gizmo to the pre-existing holes in the chassis. So I had those made at Tap Plastic.

Then there was the question of "how am I going to make the antennae?" I asked Mark what he did, and the answer (of course) was that he made them. Part of his secret weapon status is that he works in the fabrication facility of OMSI, a popular non-profit science museum in town. He helps build the electronic components of the exhibits. Mark was able to go get a couple pieces of brass rod, cut, bend, and thread them in about five minutes. Of course, on the ones he sells, he rounds the end of the pitch rod and then chrome plates them (same with the chassis), but I wasn't concerned about that for mine.

Wiring the coils was interesting. That involved the aforementioned coil winder, spools of wire on a spool holder, Mark and I, and a distance of about 20 feet. The distance was required so that one person could gently feed the wire to the other person winding the coils. The wire, particularly on the vertical loading coils, is so fragile that the person feeding the wire has to pull it very carefully so it won't break, while also maintaining slack in the line so it doesn't get broken on the other end when the winder is winding. I think the large coils took about six tries, and with the pitch coil needing 1,200 turns, you become very nervous the closer you get. The though of breaking the wire at 1,100 turns is enough to keep one up at night.

Anything else interesting? There were the usual assortment of things after the wiring was done, but all in all it went pretty smoothly. The reason for this is in no small part due to the fact that no fewer than three engineers would pop in occasionally to provide assistance and wry commentary. (One of the engineers is the recipient of a technical Emmy Award, another is one of the longest-employed and highest-level engineers at the company, so this particular theremin has been in good hands!) These guys merely had an interest in the project, from an engineering standpoint and probably because they're all musicians as well. It probably didn't hurt that there is something completely anachronistic and amusing about building a tube device in the headquarters of a cutting-edge electronics manufacturer.

It was also a sort of petri dish, or possibly a workplace pet, that everyone in our department liked to check in on now and again, with everything from serious intent to pure heckling. "Does it work yet?" "No." "Does it work yet?" "Almost there." "You ever going to finish that thing?" "Maybe."

Oh yeah, halfway through the project, my department moved across the street to a new building, and within a week of moving the office was burglarized. All the computer monitors, all the laptops, some phones. Guess what didn't get stolen, though? A big pile of parts sitting in Bill's cubicle.

Turning on the power amp for the first time was exciting. It came after a few hours of work on a Sunday and we were probably a little punch-drunk. But we were futzing with it for a while playing a CD through the line input when we noticed a little whine in the background. "What is that?" "Oh great, we'll have the pleasure of troubleshooting this now." It took us a while before we realized that IT WAS THE THEREMIN. It takes a little while to warm up and turn on, and it had just been set at a very low volume. We hooked up the pitch coil and jumped out of our seats when it responded even in a vaguely appropriate manner. We were home free!

Of course, home free still meant double-checking all the solder joints, etcetera, and that Bill needed to take it home and use his frequency counter, oscilloscope, and other gadgets to fine tune the thing. Also, for testing purposes we had simply attached everything to a piece of plywood, so it looked pretty funky.

I was scared to ship it to Portland so my wife and I devised a little driving vacation to SF around it. I couldn't get it out of the office without loud protest from my co-workers, who insisted on a demonstration, so we mocked up a goofy little PowerPoint presentation with some pictures of Lev, Samuel Hoffman, and so on. Then we gave everybody who wanted to play it a turn. It was quite fun to watch a succession of engineers, who approached it very methodically, quickly analyzing the nature of the pitch arc, then setting their arms at specific distances to test their notions of what the pitch should be, and finally jumping in and going to it. For the record, Bill played "Lara's Theme" from Dr. Zhivago and I played "Truly Scrumptious" from Chitty Chitty Bang Bang. I was told I had "wild eyes" during my performance.

We packed it up, put it in the car, picked up a friend going along for the ride, and off we went. It made it up here and after a few days I took my friend to the airport. On the way home I decided to see if any thrift stores had any furniture that I might be able to repurpose as a theremin cabinet before I broke down and built something. The very first place I went to had this funky 1970s homebrew projector box type thing labeled a "V-J Projectoscope." Because it had angled mirrors (periscope style) inside, the box was built with a wedge on its top rear. It was easy to see that with a little nipping and tucking that you could fashion a shape eerily similar to that of an RCA, and on top of everything else it was only 1.5 inches wider than the chassis, a near perfect fit. It was marked 40 dollars, which I would've turned down, but when I was walking out I noticed a sign that all furniture was marked down 50 percent that day so I got it for 20 bucks!!! It was so freaky I had to tell the clerk, who had no idea what the hell I was ranting about.

So after a few more hours of work getting the box innards out, refining the shape, building an inside shelf, cutting holes, etc., the thing is done, it looks good, it sounds good, it's funny, it's serious, I laughed, I cried, I'm glad it's over. As you can probably tell, I lucked out many times along the way. I also had plenty of headaches and groans along the way.

It's not particularly cheap. It's certainly not easy. It takes all the time you can give it. If I didn't have Bill, who is knowledgeable and was willing to commit his free time for what amounts to a fun project, it wouldn't have happened. If I didn't have the chorus of other engineers it wouldn't have happened. If I didn't have Mark Keppinger's gracious and invaluable assistance it definitely wouldn't have happened. As for me, I think my involvement amounts to equal parts investor, producer, project manager, cheerleader, and solder monkey.

If you're thinking of doing something along these lines, and you don't want to wind up with Uncle Howie's proverbial "pile o' parts that don't make a peep," listen to him, he's right. DON'T DO IT. It's way too hard and it costs way too much. It's very tedious and it takes all your free time.

On the other hand, it can also be a lot of fun and you can learn all kinds of stuff. As Principal Skinner said on the Simpsons, "Ah, there's nothing more exciting than science. You get all the fun of sitting still, being quiet, writing down numbers, paying attention. Science has it all." And if a project like this seems too daunting, you can get the PAIA kit, or something else that's less difficult. If you want to do it and think you have a reasonable ability to get it working, why listen to the naysayers?

OK, now I gotta learn how to play the thing.