Etherwave Kit Extra parts

Posted: 12/29/2010 10:03:05 AM

From: Eastleigh, Hampshire, U.K. ................................... Fred Mundell. ................................... Electronics Engineer. (Primarily Analogue) .. CV Synths 1974-1980 .. Theremin developer 2007 to present .. soon to be Developing / Trading as . ...................................

Joined: 12/7/2007

Thierry said:[i] "Can't understand why people often seem to be opposed to speaking "maths" although it is the most common and universal language to describe most of the things around us"[/i]

I dont think people are "opposed" to "speaking" math - For myself, I would love to be fluent in it, and I fully recognise that it is THE universal language by which to describe and evaluate most physical phenomena. I do not know the reason, or who to 'blame' - was it those who provided my education, or is it that I suffer from some 'impairment' (mathematical dyslexia?) - all I can say is that I have spent more time attempting to master this language than I have spent on anything else - I have gone right back to the basics, and worked through arethmetic, algebra, trig etc.. and while doing this I understand and painstakingly get the sums right .. This is also true when I get to elementary calculus - I can understand it and work with it... But a week after I have put the books down, the basic understanding remains but I get lost when doing calculations.. and 6 months later I am at pre-calculus level.

Things are improving a bit - but I have been disabled by this problem for years.. I have worked in science and technology for 30+ years.. And I know what the cost of this 'disability' has been.. I have also met many engineers and a fair number of scientists who suffer from this 'disability' - I am candid about it, and disclose this weakness to potential employers and collegues - People in science / technology tend to keep this weakness 'under wraps' and somehow manage to bluff their way through - not a game I am willing to play.

There were no electronic calculators in my day - and I find them impossible to use for complex maths anyway - unless one understands what one is trying to do, I dont think a calculator can help.. Pencil and paper are not the problem, so its probably the brain! LOL! ;-)

I have managed in electronics and physics through a sort of 'visualization' process - resorting to maths so as to tidy up component values etc.. design the circuit with a rough idea only as to optimum values, visualize the operation of the circuit to locate any potential problems, calculate optimum component values (usually using Excel), run a simulation, build it.. But for most of my best circuits I cannot say how I do it - go to sleep thinking about the problem, wake up with some bizzarre circuit in my head, draw this circuit and see how it works, then go through the optimization process described above.. The only problem I have with this is that it almost feels like cheating to say I designed the circuit!

AlKhwarizmi said:[i] "I personally would be very interested in a thread as described by Fred. That would be really nice." [/i]

If there is enough interest, we could start this in the new year - or perhaps just start it anyway.. interest can be determined as we proceed. I do not have much spare time at present, so would hope others will contribute to the 'teaching', and think the pace will probably be quite slow.


Posted: 12/29/2010 1:56:23 PM

From: Florida

Joined: 12/1/2010

Thank you all,

Yes, sadly I do not have much experience with RF or circuitry. I understand now that I shouldn't have bought a kit to do my first hand circuitry job, but when I went to order it, in the description it said "some soldering required". So in my head I thought that wouldn't be to hard, just wires to and from pots, so I took the leap. But the way I learn is by pushing my self through and by going first hand at hard challenges, as the outcome is increased knowledge for myself.

And Thierry I'm quite positive the instructions don't have those parts, as the instruction booklet provided to me is of the older Etherwave model. So I looked over all the parts and the parts in the parts list and I was able to identify all but the ones I posted in the original post.

Upon dissection of my Theremin, to put those washers in, I noticed something odd. The B5K potentiometer that was in the pitch knob slot was misshaped. I desolder the front panel and pulled out the pot. As I thought, it was severely smashed (picture below) which explains why the pot was hard to turn the knob and could also explain all the problems I've been having.

Pot Picture (

Because my Theremin is only a month old, I messaged Moog and they are offering to repair my unit for free. This is best for me as with my current knowledge I should not try to repair it and who knows what else could be damaged.

Fred, I think that thread would be a wonderful idea as it will give me one more source of knowledge to learn from
Posted: 12/29/2010 5:03:39 PM
Jeff S

From: N.E. Ohio

Joined: 2/14/2005

I haven't looked at it for quite a while, but here's a great webpage ( that Gordon brought to our attention some time ago. It's quite helpful for those of us who respond to visual aids.

Posted: 12/29/2010 7:54:59 PM

From: Croxley Green, Hertfordshire, UK

Joined: 10/5/2005

I guess the trick is to find a path into understanding electronics that suits you. Like anything else, you don't need to understand it all at once - you can achieve a lot with a subset and let your understanding grow over time.

The subset that has caught my interest is the 4000 series of CMOS logic chips. They are fairly straight forward to use - a 9 volt battery will power them happily and they require only a few support components before you can start getting sounds out of them. And my computer background gives me a comfort zone thinking about them as logic components without worrying about the low level electronics of them. This is prior knowledge that I can use as a starting point.

Musically they have some major drawbacks - you are stuck with a fixed waveform (square) and a fixed amplitude, but that allows me to think about frequency alone, and to know that when I am ready to take the next step into slightly more general audio circuitry I have some specific requirements to address.

It also helps that there are a fair number of audio circuits freely available on the web that are based around 4000 chips, and I am currently at the stage - having built a couple of simple circuits (*) by copying existing circuits exactly - of constructing a new circuit by putting together blocks of circuitry that are parts of published circuits. I anticipate that as my confidence increases I'll proceed step by step to designs that are based more on my own understanding and less on copying other people's work.

I should also mention that electronics experts on the web - at least the ones I have encountered here and on the forums (the 4000 series stuff is in the "lunettas" forum) are helpful and understanding of novice questions.

I think in the music area it is not uncommon for an interest in making music to lead to an interest in wielding a soldering iron (not least to repair expensive audio cables that got the wire jerked from the jack plug) so they get plenty of enquiries from people without a background in maths or physics. :-)

(*) Not the prettiest of sounds - but a great participation sport; twiddling the knobs and hearing what happens is fun. Nonetheless - Video 1 (, Video 2 ( I prefer 1 to 2.

You must be logged in to post a reply. Please log in or register for a new account.