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VM-3024S/H Instruction Manual
(Compatible with Version 2.16 or later)
10. How to Fix the Pickup and Frequency Characteristics
When a vibration pickup is attached to a vibrating body, a single vibration system is
formed at the contact area, and the natural frequency of that system is determined. This is
called the contact resonance frequency.
The contact resonance frequency varies depending on the fixing method and contact state
between the base of the vibration pickup and the surface of the vibrating body, and
particularly affects the high frequency characteristics.
Pickup fixing methods include (1) Screw mounting, (2) Instant adhesive, (3) Double-sided
adhesive tape (thin and strong material), (4) Magnet, and (5) pressed by hand (Fig.10-1).
The contact resonance frequency by these methods is above 2kHz and has not almost
affect, but contact resonance frequency about (5-2) pressed by hand (using contact pins), this
becomes around 1.5kHz shown Fig.10-2 (next page). And it is careful for the indicated value
becomes large at 500Hz or more.
(1) Consider the fixing method if necessary.
(2) If the tip contact surface of the detector probe is inclined, correct measurement cannot
be performed.
(3) The pickup may be damaged by a strong impact (100m/s
2
). Please handle with care.
(1) Screw
(2) Adhesive
(3) Double-sided Tape
(4) Magnet
(5) Pressed by Hand
(6) Pointing Up or Angle
(5-1)
(5-2)
Fig.10-1 How to Fix the pickup
