My Construction of the EW Theremin

Posted: 9/6/2009 11:39:52 PM
Eddie

From: Tennessee

Joined: 7/6/2009

Well, the end is coming soon... along with my Student Loans... (Dreading this).. Anyhow It has been a while since I have posted anything due to being swamped with work, school, and being sick the last 2 days. Here's a bit of what I accomplished in the last two days for my capstone project.

Eddie's Theremin (http://s682.photobucket.com/albums/vv184/kidohs_theremin/)

(Hopefully I did this correct... First time posting a link here)

In case the link doesn't work as planned, you can copy and paste this:

http://s682.photobucket.com/albums/vv184/kidohs_theremin/

Laying out the PC Board was a bit tricky as I was trying to get the components near the same place as the photos that I found on the internet of a finished one that starter as a kit.

Not quite sure how well it is going to do since I have the VCC and VEE and Ground traces all on one side. I was able to draw this board without using a double sided board....

The large board in the photos is for the main circuit, (like you couldn't already figure that out), but the small one is for the output and headphone jacks.

I also found on the forums a jig to bend the antenna, I made a couple of changes to the jig, but it worked just fine. Now all I have to do is find out what frequency the volume side is operating on, and cut the antenna to length. The same goes for the pitch antenna. I can not find any information on how long it is, just somewhere around 17 - 19 inches long...

I have been thinking about lining the wooden box with tinfoil to act as a ground plane / shield. If you have any suggestions about this, I would greatly appreciate it.

The box that I am going to build will be out of black walnut and I will clear coat it when it is all sanded down. This should make it look pretty nice.

All in all, I have less than $200.00 USD involved and that includes the wood for the jig, PC Board and supplies, The two antennae and compression fittings, and all the mods. Not quite sure if I want to add the CV or Tuner mod, as I won't be using either one. The cost is actually a lot less when you figure out that you have to buy 10 resistors to get only one that you are going to use. I have been keeping a running total of all the parts and shipping.

As I continue on with this project, I will update this and the photos accordingly.

Since the witching hour has come and gone, I guess I better hit the bed and get some sleep.

Posted: 9/7/2009 5:06:52 AM
GordonC

From: Croxley Green, Hertfordshire, UK

Joined: 10/5/2005

Link works fine.

Good looking face plate - nice bright readable lettering, and the word Theremin in a wicked font - presumably in case you forget what you're playing. :-)
Posted: 9/7/2009 8:18:06 PM
Eddie

From: Tennessee

Joined: 7/6/2009

Well thank-you GordonC.

Here are some new photos as of tonight. I have the main board and the Headphone/Output board populated and getting ready to clean up my area and do some testing to make sure everything works properly and that all my voltages are correct.

Wow, what a long sentence! Anyhow, here's the link to the pictures again:

Eddie's Theremin Photos (http://s682.photobucket.com/albums/vv184/kidohs_theremin/)

Maybe this will inspire a few to build a few more of these... It sure is a heck of a lot cheaper than buying one!
Posted: 9/7/2009 8:58:13 PM
teslatheremin

From: Toledo, Ohio United States of America

Joined: 2/22/2006

I must agree with Gordon C.: The stencil work and knobs are truly Sweet!
Nice!
Good Luck!
teslatheremin
Posted: 9/8/2009 1:02:22 PM
Eddie

From: Tennessee

Joined: 7/6/2009

Thanks for the compliments teslatheremin. I have been doing this type of thing (electronics building) for many years now. The knobs I got from a company called OKW. Their website is OKW USA (http://www.okwenclosures.com/)
and their part number is A 13 21 060. They are really some "Old Timey" like knobs.

I always liked the nostalgic look when it comes to electronics. When I was growing up, things tended to last a whole lot longer than what they do today. They just don't make things to last anymore. It's a throw-a-way world now.

Anyhow, thanks again for the comments!!
Posted: 9/9/2009 12:15:08 AM
Eddie

From: Tennessee

Joined: 7/6/2009

Well, I connected the faceplate to the main board today and used 2 6" pieces of wire to do some testing of the EM Theremin I built and constructed, and what do you know, it worked right out of the gate. No problems with it at all. It's always fun to know if you forgot a trace or two on the board, AFTER the fact, but I got everything right! So now, I am off to building the EW Theremin for my next one. Capstone project or not... Theremins are really fun little instruments!
Posted: 9/9/2009 9:08:02 PM
teslatheremin

From: Toledo, Ohio United States of America

Joined: 2/22/2006

Please, post some pics and sound-files of this sweet Theremin build--- I am sure there are a few lurkers,(besides the Lookers), here that would like to have that experience.
Good Luck!
teslatheremin
P.S.--- Can I buy one of those fantastic circuit boards?
Posted: 9/11/2009 4:43:08 AM
Eddie

From: Tennessee

Joined: 7/6/2009

teslatheremin,
As of yet, this is the only theremin board that I have etched out. I will, in the very near future, make a few more of them and yes, it is very likely that I will sell them.

At this point, I am not sure what they will cost, but I will have the output / head phone boards, the control voltage / tuner board also. I am thinking about making the theremin board so that it is capable to build EITHER the EM or the EW theremins on the same board. The only differences is a few parts and the addition of 3 fixed inductors for the oscillator circuits.

When I get a few moments and get the unit into a box, I will post some more photos along with some sound files. Please note though, that I have NEVER played one of these before... So don't be looking for a symphony... HA!HA! Also note that some of the parts for the EM Theremin are extremely hard to come by. It has taken me a long time to locate some of them but they can be found if you look hard enough.

Thank-you for the compliments on my theremin build! I appreciate it a lot!

Eddie

Posted: 9/11/2009 12:08:06 PM
ericr

From: Victoria, Canada

Joined: 9/4/2009

VERY very cool wook!

I hadn't heard of the "EM" theremin before, was that a precursor to the EW?

(Also, count me in for a set of boards if you make some for sale!)

-eric.


Posted: 9/11/2009 11:56:08 PM
Eddie

From: Tennessee

Joined: 7/6/2009

Eric,
Yes, the EM Theremin was designed before the EW Theremin. Many of the parts for the EM Theremin were becoming harder and harder to find, so the EW Theremin has less tuning range in the variable inductors because the circuit for the EW Theremin has fixed inductors in series with them. Along with these being changed, so were a few of the capacitors and resistor values.

Both of the Theremins are based on the same voltages and design. There are 26 differences between the Em and EW Theremin, (Including the mods for the EW Theremin). If you would like a list of the changes, I can email them.

Thanks for the compliments on my EM Theremin project! I Appreciate it!!!!

Eddie

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