some assistance in tuning required

hello there,

I'm a complete beginner and just got an Etherwave Plus (along with a Behringer K450-FX and some headphones to keep my neighbours happy) Everything works as expected but I'm wondering about the tuning.
I'm a complete idiot when it comes to notes and such but I would say I have a pretty good ear.
I followed instructions and watched a lot of youtube videos (long live internet) but I have the feeling that something is not right. When I try to adjust the pitch it feels like the range is very limited. In order to get the lowest tone within an arm length the pitch knob ends up at 9 (clock). (As I understand, the further to the left the more the field gets expanded) Using that pitch adjustment I have to more or less move my whole body in order to play like this melody. When I turn the pitch clockwise the range gets even smaller and after 12 it's backwards (nothing close to my body, then high pitch getting deeper the closer I get to the antenna)

Working in IT I consider the following options:* device faulty (package was pretty damaged on delivery)
* environment (there is a large table with metal frames around- I moved the theremin as far away as I could but my living room is not that big)
* my arms are too short (I'm not that small)
* I'm doing something wrong (most likely)

I'm not that eager to play one octave out of my wrist (I wouldn't mind though) but at least being able to play a simple melody without looking like a lunatic would be great. (Maybe I should get myself some curtains- neighbours across my street seem to have fun already)

Any ideas what to try?

So much fun to be had tuning the EW!  The instructions that came with my EWS kit were pretty useless.

Metal stuff 4' or so away won't bother it too much.  Make sure it's mounted on a mic stand and not sitting on a table or whatever.  You will probably end up taking the top of it off, which will probably make the tuning worse while it is off.  If you're definitely going to keep it I'd recommend you drill holes in the top to get at the transformer slugs with the top on.  My method of tuning is with an oscilloscope probe placed near the pitch antenna, adjusting the variable pitch oscillator for maximum voltage, then adjusting the fixed pitch oscillator for null, going back and forth between them until I get exhausted and feel the need for a stiff drink.

Hmm, getting an analogue device, I was naive thinking that it doesn't require any tweaking...
Mic stand = check. (re-discovering my neighbourhood in search of a thread reducer = great music shop nearby!)

Since this is the first instrument I've ever bought myself, I definitely won't sell it. (maybe give it to someone who is more talented but first I want to try myself)

I don't have an oscilloscope at home (who does?) but if this is the way to go, I need to beg my hardware colleagues at work to assist me.

Just to be on the safe side- do you think it's broken or is your suggestion based on personal experience?

Anyway- Thanks for your input.

"Hmm, getting an analogue device, I was naive thinking that it doesn't require any tweaking..."

At least you dont need to wait until a software update is released to get it functional ;-)

"Just to be on the safe side- do you think it's broken or is your suggestion based on personal experience?"  - madigan

Since you say the "package was pretty damaged on delivery" anything is possible.  I'd take the top off and see if there is any obvious damage to the circuitry.  That it works at all is a very good sign.  My experience (I owned an Etherwave Standard) is that unless an EW is tuned somewhere near correctly it won't behave the best.  But I haven't devoted much of my life to tuning parallel tank Theremins (and plan to keep it that way) so I'm probably not the best person to talk to here at TW.

If / when you get it tuned (if indeed that is the problem) don't be overly concerned about the orientation of the pitch knob.  If it gives you enough range to null it plus a little extra wiggle room that should be OK.

At least you dont need to wait until a software update is released to get it functional

That's at least something- it's a major part of my job to push developers for releases ;-P

Thanks, dewster. I can have a look into the inside myself but I guess I won't get much of an insight- maybe I should first try to find someone who is familiar with tuning and being able to place me in the right spot (I tend to move a lot when standing- I know, not the perfect preconditions)

Otherwise I'd appreciate some further advice from you if it's really necessary to get my new little wooden box to my colleagues (I'd rather avoid that ;-) )

Just to let you know that I made some progress.. ;-)

First of all I I now realized that my thread title was pretty misleading- I actually was referring to tuning the device using the pitch knob. dewster fortunately pointed me in the right direction and after a bit of research and a trip to my basement (I'm glad I stored the packing there and could find the tuning tool which I didn't see when unpacking the etherwave) I spent a few hours fiddling around with L5 and L6. At some point I got completely confused following different instructions and ended up with a complete mess.

However, eventually I succeeded and even though I'm not 100% satisfied yet, it behaves way better than it did initially. The pitch knob now does what it's supposed to do (or at least what I expect)

So there is only one thing left I'm wondering about: when I move my hand towards the pitch antenna, the tune gets higher as expected. But when I touch the antenna, release it and move the opposite direction the pitch gets even higher for a very short range, then there is a gap of silence and then the tone will continue to get deeper again.

I find that quite strange- within the same distance from the antenna the behaviour is totally different, depending on the direction of my movement. Well, it's not such a big problem for me. Just that I didn't put the screws back in yet, still in the mood of experimenting. Is this normal behaviour or should I try to correct this (and if so: how?)

"So there is only one thing left I'm wondering about: when I move my hand towards the pitch antenna, the tune gets higher as expected. But when I touch the antenna, release it and move the opposite direction the pitch gets even higher for a very short range, then there is a gap of silence and then the tone will continue to get deeper again.

I find that quite strange- within the same distance from the antenna the behaviour is totally different, depending on the direction of my movement. Well, it's not such a big problem for me. Just that I didn't put the screws back in yet, still in the mood of experimenting. Is this normal behaviour or should I try to correct this (and if so: how?)"

It's simply "over-tuned". That means that you lowered the frequency of the variable pitch oscillator too much. Turn the slug of L5 1/2 turn clockwise and then adjust L6 so that the zero beat point* is about 4" from the pitch antenna while the lid is open and the pitch knob is in its center position. Close the lid. Check now if a) you can tune it for zero beat at about 20" away from the pitch antenna, and b) this frequency jump effect does not longer appear. If not, repeat the above steps.

Once this obtained, do not longer touch at L5 and make slight corrections with L6 to re-center the pitch knob if needed.

*zero beat is the point where audio stops after going lower while moving your hand away from the antenna. When moving still more far away, audio should re-appear and start slowly from low frequencies. Having a "negative beat zone" (reversed pitch field) behind the zero beat point is normal behavior, as long as the positive beat zone is wide enough (between 16" and 24") adjustable with the pitch tuning knob.

heres the link to the Moog forum and Amos instructions on tuning - I cannot vouch for these instructions, but some folks (at least one ;-) here at TW has used it.

http://forum.moogmusic.com/viewtopic.php?p=60972

Fred.