[i]"Well, Fred's already designed something a whole lot better than what I had in mind!" - Don[/i]
Don, "better" is an "application specific" word! (LOL).
My design is much more complex than the simple solution of using standard Theremin circuits to build a stand-alone volume unit.. and if one is only after volume control where precise capacitance to voltage output is not required, then it is still a viable (and probably cheaper) option.
I am hoping to get the cost down by having a large production run, and using the modules for lots of applications - but if I did not have this cost reduction route, I doubt that I would sell many.. I have been forced to submit to constraints I have resisted until now - going to SMD for example (required because these are cheaper to get made, and because I need to encapsulate).
I have the prototype built with components I can see - there is one component I cannot get in leaded form, and I lost 4 of these before I managed to solder one to the PCB! - When I say lost, I mean lost - They were being held in my tweezers, and just dissapeared! I was wearing a 'microscope' on my head, and even with this, seeing the bl**dy part to hold it (let alone solder it) was damn near impossible.
I am now laying out a board and all the components will be SMD - I have absolutely no chance of assembling these boards myself - so must get a batch built, and test them - I must get it absolutely right first time, as debugging the module will be virtually impossible, and I cannot afford the cost of doing it again..
I think some DIY constructors will be put off by the fact that they cannot play with the innards (for all practical purposes, the module will be an IC) and there may well be a market for a good old-fashoned volume circuit board people can fiddle with!
And a word of advice to everyone - Dont be put off doing something because you are waiting for me! .. I am not reliable when it comes to time management - I have every intention of making my modules available this year, and things are looking promising for me to be able to achieve this - BUT - I have let a lot of people down in the last couple of years. I was wrong to mention my plans, and wrong to "leak a squeek" about them.. I have one absolute committment - At Hands Off 2011 I will have products for people to play with and buy - I cannot fail to meet this target - if I did, I will be out of business - I have used up every reserve I had and borrowed every penny I can - 2011 is my deadline year - but fortunately, 11 is my lucky number! ;-) [i]no.. I dont really believe in lucky numbers - i'm too scientific for that.. ;-) [/i]
Punchline though, is that for constructing a simple volume controller, my modules will be a more expensive route than what this application needs - The market for a simple capacitive volume controller will go to the lowest cost unit which performs the function - and my modules will be more expensive and would probably be gross 'overkill' if used only for volume control.. It is when one gets to 'higher end' products (requiring 2 or more precise sensors) that my modules will be unbeatable.. A volume controller with stereo panning or VCF control assigned to the X vector, and the 'E-Joystick' using 4 sensors, or a controller using one sensor for volume and one for pitch.. these are among the type of product I am targeting - products where the sensors need to be precise, analogue, stable and absolutely predictable.. and where one can use as many sensors as required without worrying about antenna interaction.
Fred.
