Building and using an inexpensive impedance head
نویسنده
چکیده
As a sound source, this design uses a piezoelectric “buzzer” disk, which has a high acoustical impedance and is therefore not strongly affected by the air column’s own resonances. Buzzers with housings such as Radio Shack 273-073 or 273-064 are easy to find and have leads attached, but they must be disassembled in order to remove the brass disk with the piezoelectric element. Or, the disk itself can be obtained from electronics supply houses such as Mouser or Digi-Key.
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