I know it is probably not my place to give this 'lecture' - but sod it! There are a few of us on this particular forum who carry most of the 'weight' - I, for one, enjoy this role - but spare time available to all of us, is a limited commodity.
So PLEASE .. Spend some time forming your question, and PLEASE Give ALL the information relevant to the enquiry - Relevant information includes, but is not limited to:
The Make, Model, or Schematic if you are building a Theremin... Identify the project CLEARLY!
A LINK to the relevant website where data (construction plans, schematics etc) can be found.
Some information on your technical competency.
Details of ANY modification you are making / intend to make, to the Theremin or project you are discussing.
[b]TELL US if what you are doing is a college or university project[/b] - It makes ALL the difference to how we address your enquiry! We are [b]HAPPY to help students[/b] - but it gets frustrating to find out, after giving advice, that you have no interest in a good playable Theremin - all you want is to pass! ... [b]We can HELP YOU TO PASS easier if we know you are a student![/b]
If you are a student, tell us EXACTLY what you have been instructed to design / build.. What you may NOT do, and what you MUST do.. And also tell us HOW MUCH TIME you have to do it - and ANY other constraints, such as parts you MUST or MUST NOT use, cost constraints etc.