0 Replies Latest reply on Dec 15, 2012 5:37 PM by FredM

    Linearity of different topologies

    FredM

      I am exploring different linearization methods for theremin front-ends. This is the first in what I hope will be a series, as / if I progress.

      I also plan to 'publish' the spreadsheets here.

       

      First is a 555 based RC oscillator. The operating frequencies and component values where 'chosen' by substituting values in the spreadsheet.

       

      Many factors influence the resulting plot - But for this topology linearity is poor, and useful playing range extends no further than 50cm at best, with 3 reasonably linear octaves.

       

      Click on the images for full size.

       

      RC555_CCTVAL1.GIF

       

      RC555_CHART2m.GIF

       

      RC555_CHART1.GIF