Azimuth Adjustment - Sony BS78 Series Instruction Manual

3-4-2. Azimuth Adjustment

The direction shown in the figure below is referred to as the azimuth direction. A stable output signal of the
specified value (amplitude: 1.6 Vp-p) or higher can be obtained by adjusting the detector head direction.
Azimuth direction
1
Loosen the detector head mounting screws.
2
Rotate the detector head as shown in Fig. 3-18, until you find the point where the amplitude of the
Lissajous' figure is at a maximum.
3
Alternately tighten the two detector head mounting screws little by little at the detector head position
with the maximum amplitude of the Lissajous' figure. (Fastening torque: 0.8 N . m)
4
Check that there is no interference between the scale and detector head, and make sure that there is a gap
of 2 ± 0.2 mm as shown in Fig. 3-19.
Detector haed
5
Move the scale, and make sure that the amplitudes A and B of the Lissajous' figure (see Fig. 3-20) are
1.6 Vp-p or greater over the entire length.
n
If the output of 1.6 Vp-p cannot be obtained even through repeated adjustment, recheck the mounting
surface accuracy of the scale and detector head (refer to pages 5 to 7), and check again that there is no
dirt on the scale's surface.
Lissajous
14
(E)
Azimuth direction
Fig. 3-18
2 ±0.2
Check for interference
Fig. 3-19
A
B
Fig. 3-20
Scale
BS78