Tuning fork
9
EN
This is done as follows:
The tuning fork will struck against the ball of the thumb with the dampers (the sound
C=64z). Initially, by the strong vibration of the prong of the tuning fork both triangles are
blurry to see.
After a few seconds, depending on the striking strength, the triangles start to be clearly
visible at the baseline. In addition, they grow slowly, that means with slowly decreasing
amount of the intensity of vibration until the first, second, third, etc. cross of the scale.
So, the examination can be started each at a particular cross of the scale.
This can be read off either the white or the black triangle, depending on the amount of
light, available or which scale is more easily readable.
4.2 HB 0181-06 Tuning fork with damper and base, adjustable from c
128 to h 240
The Lucae-tuning fork produces 7 different frequencies, from c 128 to h 240.
The exact frequencies are listed in the following table:
c
d
e
f
g
a
h
Frequence in Hz
128
144
160
170,66
192
212,33
240
The change of the frequency will carry out by moving the weights at the prongs. These
weights can be adjusted manually.
When the sound is changing, the spring in the weight have to lock in the groove of the
tuning fork. Only therefore an exact frequency can be reached.
Both weights have
to be always on the same level. Are the weights on different levels, it’s
not possible to produce an intermediate sound.
The stamped letter directly under the weight identifies the produced sound.
Summary of Contents for HB 0181-06
Page 2: ......
