Sony Magnescale GB-A Serie Bedienungsanleitung Seite 80

Perform the electrical adjustment while moving the scale.
【Reference】Trigger
When using a 2-channel oscilloscope with two probes,
the trigger can be applied easily by connecting the open
probe to the EX terminal on the board and the ground clip
to the GND terminal. Therefore, this method is
recommended.
1 Prepare the oscilloscope by setting the input coupled
switching to AC with a horizontal sweep axis of 10 µs/
div and a vertical axis of 0.5 V/div, and connecting CH1
to the PM terminal. At this time, the trigger source
should be taken from INT CH1.
2 A sine wave appears in CH1. The phase of this sine
wave moves in accordance with the scale movement,
allowing the envelope ripple to be observed. First
rotate the RV2 volume to set the sine wave amplitude
to approximately 2 Vp-p. (This is called the gain
adjustment.)
3 When the RV1 volume is rotated completely to the right
(clockwise) and the scale is moved, the waveform
shown in Fig. 4-7 appears. At this point, adjust the RV4
volume so that neighboring peaks are of the same
height as shown in Fig. 4-8 (This is called the DC
balance adjustment.) If the minimum PM signal
amplitude falls to 0.5 Vp-p or less, the alarm function
may operate.
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Fig. 4-7
Fig. 4-8