LEFT HANDED?

In theory you are completely right and that seems to be a brilliant idea!

BTW: The EPro has the linearisation parts for each antenna on a separate board...

FredM may not be an expert... but he sure knows a lot..."sensitive to changes of a few femto farads.. howvever, on the other side of the EQ coil, one can get away with adding several picofarads if you needed to".. what the heck are femto farads and picofarads? Having not seen the inside of one of these babys, I'm gonna go ahead with Andy's info that it is possible to wire the kit left handed. Thanks to all for your help. Jim

One of the nice things about putting the circut board upside down is you can access the fine tuning coils without having to take the top off. just make sure you align the holes with the coils when you drill them.
I'm surprised they removed putting a EW together left handed.
When I first bult mine, the instructions said to build your new theremin left handed you must first... then blank pages.

I called Moog, then Big Briar, and they told me what to do. So I don't know if they added the instructions, or just plain deleted them.

Good luck,
Andy

JimD wrote: [i]"FredM may not be an expert... but he sure knows a lot..."sensitive to changes of a few femto farads.. howvever, on the other side of the EQ coil, one can get away with adding several picofarads if you needed to".. what the heck are femto farads and picofarads? Having not seen the inside of one of these babys, I'm gonna go ahead with Andy's info that it is possible to wire the kit left handed. Thanks to all for your help. Jim"[/i]

How dopey can one be?

FredM takes the time and explains in a very precise and detailed manner what may be possible and what is not. And that one may just not wire the thing the other way round without further precautions.

But if a JimD who even knows nothing about capacitance units what disqualifies him completely as a theremin builder will wire an Etherwave kit simply the other way round, let him do this and fall flat on his face...

[i]"In theory you are completely right and that seems to be a brilliant idea!"[/i]

Thank you, Thierry ! ;-)

[i]"BTW: The EPro has the linearisation parts for each antenna on a separate board..." - Thierry [/i]

This would undoubtably be the best way to do it.. remove the EQ coils from the EW, and mount these on independent boards, copying any layout of the original (as I understand it, the new EWs have coils lined up -|-| ?) .. This should not actually require a PCB - it could be done on pieces of SRBP prototyping board (like this one) (http://uk.farnell.com/roth-elektronik/re200-hp/pcb-eurocard-fr2-2-54mm/dp/1172146?Ntt=117-2146) or epoxy board (like this) (http://uk.farnell.com/roth-elektronik/re200-lf/pcb-eurocard-fr2-2-54mm/dp/1172148?Ntt=117-2148) or any equivalent proto board which dous not have tracks, but only has holes with round or square copper pads.

One then simply places these boards close to their respective antennas, and wires them to the circuit (volume or pitch) which is appropriate.

Dont know the difference between a femto and a pico? - Do yourself a favour and get some basic education.. check it out here for starters: Power Prefixes (http://www.knowledgedoor.com/1/Unit_Conversion/Power_Prefixes.htm).. but the bottom line is that a femto Farad is 10e-15 Farads, a pico Farad is 10e-12 farads, so one femto Farad is 1/1000 pico Farads..

Changes of less than 1/8 pF (picoFarad) (1/8pF = 0.125pF = 125fF = 125 femto Farads) are enough to give major changes in the oscillator frequency if applied to the antenna side of the EQ coil.. However, similar changes on the oscillator side will have extremely reduced effect .. one would need to have a change of several pF on the oscillator side to be able to notice even slight change in oscillator frequency.. and one could quite happily add or subtract about 100pF on the oscillator side and still be able to achieve tuning - the 3300pF capacitor connected across the oscillator coil probably has a tolerance of +/-10%, so there are +/-330pF ... This IS the right place to connect any wire if one wants to move the antennas.

Move the antennas, Move the coils, LEAVE EVERYTHING ELSE THE WAY IT IS..

Or ignore this advice and stand a high chance of turning your theremin into nothing more than a squeeky box!

Whilst I do not have expierience with any "genuine" EW, I do know the theory works.. The Theremins I am designing cater for left and right handed players - simply swap the antennas over (they have multi-pin, screw locking threaded connectors) and the pitch and volume functions follow the antenna.. I have done this using exactly the method described above (and using screened RF Co-Ax cable to connect between the circuits and the duplicated equalizing coils)

I know zero about electronics.

I built two EW's the way I described it and they both play perfectly, well as well as a first year version of the kit can play.

Andy

[i]"I built two EW's the way I described it and they both play perfectly, well as well as a first year version of the kit can play." - Andy [/i]

Sorry Andy - I never meant to 'knock' anything you said.. Your method should work just as well - you are not lengthening the antenna leads by doing this, and provided the capacitance seen by the antenna leads is within the required specification, and no other interfering items such as the case / screws / screening exist, it should be fine.. As I say, I dont know the EW.

For me (as an electronics bod) the idea of drilling holes and getting special mechanical bits, and turning a board upside down, is horror! - Perhaps someone who does not know electronics has the opposite reaction, and the idea of moving inductors fills them with horror!

And sorry Jim - I was probably a bit harsh with the "basic education" - I suppose most people's understanding of units is limited to "inches" and "millimeters" - Perhaps micro, milli, centi, kilo and mega are the limits that people usually encounter.. femto is quite rare, even in electronics.
;-)

[i]Your method should work just as well - you are not lengthening the antenna leads by doing this, and provided the capacitance seen by the antenna leads is within the required specification,[/i]
I was told this way by Bob Moog himself. It's a lot quicker than moving things around. It took longer to drill the holes than to do the wiring. Like I said before, the nice thing about putting the board in upside down with holes in the bottom is you retune and fine tune without having to take off the top.
I understand that people who enjoy working with electronics,can and judging from the posts, will come up with interesting ways. I can see how it can be an enjoyable project. It's like Coalport taking apart his theremins just to see what's there, or like his over haul of his EPro.

I have friends who do like to do things like that, and would love to rework the circut to make it left handed and Theirry's godsend mod will go down in theremin history.

I'm just happy to be able to play.

Andy

I built my EW Plus kit as a left handed and it works fine. Easy if you know how.

The holes on the left and right side are not on the right place for the antennas if you want to build it left handed.

The print upside down with spacers/bushing/distance bus (sorry, don't know the English word) is as far as I can see no problem.

As far as I remember used Wilco Botermans from The Netherlands (http://ethermagic.eu/) new left and right wooden ends for replacement for left handed Etherwaves. Maybe you can ask him for details (and share it here).