Keppinger tube theremin builders - Finding Parts

Check into the Yahoo Group, kepptheremins. There is a lot of info in one place here. Also, my site is at

http://www.neidlinger.us/keppinger.htm

Good luck. Take your time, don't get in a hurry, and it will likely not go POOF on first power up!
(just kidding).

Philip Neidlinger

littlefrank - The double-layer coil(s) you are referring to are for the 1929 RCA AR-1264 theremin!

The document you have is a confusing mix of coil details for the Keppinger theremin and the RCA theremin. The Keppinger supplied schematic is barely legible and there were variations and modifications that were not documented.

That is why I spent a great deal of time and effort to bring some clarity to the situation (with the help of a number of people who have been acknowledged on my documents).

Hypergolic,

I’ve visited your site and the outline and pictures should prove very helpful in laying out and constructing the project. Thanks for your work. I’ll check out the Yahoo Groups. I’ve procured just about everything but the chassis, which I’m planning on building myself.

Jeff S,

I’ll stick to your plans, they are pretty clear and concise, and along with pictures from other sites I think I can make it all work. I do have access to an AR-1264 which I can refer to for details towards making it look like a reasonable reproduction.

As for time and patience, I figure this will keep me busy through the winter.

Thanks for your help and advice.

... and those tubes should keep you warm during the winter, too. :)

Good luck on your project!
Check on Mouser, Antique Electronics, and ohter sites for aluminum chassis. Those are easier to work with than trying to do the whole thing from scratch.

Greenlee punches are the perfect thing to cut the holes for tube sockets, but they are very expensive. If you are going to use hole saws, don't buy the cheap ones. Spend the extra money for just the sizes you need.

Don

Okay Chobbs, at $200 your coil set is a bargain. But I guess I'm officially a nerd because I wound a pretty decent looking L6 this afternoon (and evening). It may have a crossover or two (I backed off and fixed about a half dozen that I caught)but I don't think it matters anyway. And there are a few slight imperfections here and there where one strand looks like it may have road up a bit between the adjacent windings. That's the big one and the others should go much easier. I'm going to put a couple of coats of spray shellac on them to protect the windings. If they don't test out for some reason I'll definitely consider buying a set from you 'cause that was hard. But it looks good and I'm happy to have tackled that challenge. Thanks for advice.

Hey littlefrank, Im sure your L6 is fine. But if you are patient, you can work the crossovers out toward the ends. While its not fun, it its possible to tidy up the windings quite a bit post-game.

By the way... if you need the chassis sets, probably the easiest/ cheapest solution is get a pre-made set from levnet member Daniel Schreiber. As of last week, he had a couple sets available on ebay for a ridiculously low price of about $60! Thats TWO custom 16 gauge steel chassis, with everything pre-punched-pretty much an exact replica of the original KEP's- for like $30 a piece. A blank chassis (from Antique Electric supply)will probably run $20+
Also 15" X 6.5" pretty unique chassis size

Recommendation: You can drill one less hole if you incorporate the volume and on/off switch into one control.

I'd love to find out where to get some cloth covered three wire cord for mine. I use a computer power cord that's had the female end cut off, but its not too flexible.

Radio Daze is another good spot for parts. Also, post on Levnet and ask around, you may get lucky.

I got my coils for the purchase price of a water pick. I didn't savor the possibility of having to wind my own coils.

Good luck.

Philip

By the way, I'm leaning on Gabriella in my profile photo.

I also have a collection of old electric fans and I'm always concered with using them as wired with two-conductor cord, especially when I give one to a relative. I can take a shock now and then as long as it's not across the heart, but most peole freak out when zapped and are not as aware and cautious when dealing with an ungrounded appliance.

Here is your wire http://www.sundialwire.com/3-conductor-1.aspx

I use a site called thefind.com to search for stuff like this. It's geared towards merchandise and filters out all the crap you get with google.

I been looking for this stuff myself and had thought that it didn't exist. Thanks for making me look.

Regarding the wiring of those old fans ...

I had a very unpleasant experience with an old AC motor. On some old electrical gear you can just tie the ground wire to the frame and it works fine. That was not the case with this motor. Apparently there was some connection to the case and I fried the motor. If it were just a short-circuit from the hot side to case it would have blown the circuit breaker in the house panel.

I also have an old Sears electric drill that has some sort of leakage issue ... it will zap you sometimes. I don't use it at all now!