• Ken Taylor
  • email : kentaylo@swbell.net

    Frequency divider for standing wave vibrators


    A simple electronic approach has been taken to modify the frequency of vibration of "standard" fixed-frequency vibrators used for generating standing waves on strings. These generators run off 60-Hz lines and generate standing waves haveing a frequency of 120 Hz. The frequency division is discrete.

    Sketch of the apparatus

    (faxed in, maybe scanned later)


    A fixed-frequency vibrator (#1 in above sketch) which typically runs off a 120-V 60-Hz line is used for setting up a standing wave pattern in a string. Slotted weights (#4 in the sketch) suspended from a pulley (#3) create the required tension in the string (#2). The apparatus is modified from the stadard assembly by an electronic circuit which is housed in a box (#5) into which the vibrator power cord is plugged. The frequency modifier box is then plugged into the standard wall outlet. A switch provided on the modifier box allows one to select the desired frequency for driving the standing waves.