How to change frequency of HALL signal

Discussion in 'The Projects Forum' started by sl33k3r, Apr 25, 2012.

  1. sl33k3r

    Thread Starter New Member

    Apr 25, 2012
    Hello, I need a device to detect a signal from a HALL sensor then change (adjustable) the frequency plus or minus up to at least 15%.

    It would need to determine and store frequency of input, add/subtract timing offset to obtain required output frequency, store output frequency, then output that frequency until the input frequency changes.

    That is generally what happens. I know there should be some more conditional statements, but that is a simple example.

    Where would I start? (Besides a college electronic course)

    Thank you
  2. wayneh


    Sep 9, 2010
    A kludge solution: Use two circuits, a frequency to voltage converter followed by a VCO voltage controlled oscillator. Not elegant but it would give you a wide range of control. And both basic circuits are easy to find for the 555 timer IC.
  3. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    Google for "speedo recalibrator". They do exactly what you need, there are a few proven commercial products in the $90 to $100 range.
  4. sl33k3r

    Thread Starter New Member

    Apr 25, 2012
    Thank you very much for your suggestions. They have not gone unappreciated.