TAS 200 Series Adjustment Procedures
40
Handheld and Benchtop Instruments Basic Service
TRIGGER SET TO 50% In
TRIGGER SLOPE Falling (push switch in)
2. Use a DMM to measure the collector voltage of Q414. Adjust VR403 for a
reading of 1.40 V ±0.02 V. See Figure 10 for the adjustment location.
3. Set the CH 1 GND push switch to the out position.
4. Connect a 50 kHz sine wave to the CH 1 input. Adjust the generator output
to produce a waveform four divisions in amplitude on the display.
5. Alternate the TRIGGER SLOPE push switch between the rising (in) and
falling (out) slope settings. Adjust VR403 for a 0.4 division downward
vertical shift at the beginning of the sweep. See Figure 10 for the adjustment
location.
Use the following procedure to adjust the trigger center.
1. Set up the oscilloscope as follows:
HORIZONTAL SEC/DIV 1 ms
TRIGGER SOURCE CH 1
TRIGGER SET TO 50% In
CH 1 AC-DC AC
2. Connect a 50 kHz sine wave to the CH 1 input. Adjust the generator output
to produce a waveform eight divisions in amplitude on the display.
3. Verify that the trigger point is within ±1.5 divisions of the signal swing
center.
4. Readjust the oscilloscope controls as follows:
TRIGGER SET TO 50% Out
TRIGGER LEVEL Midway
5. Adjust VR407 to position the trigger points equidistant from the center
horizontal graticule line. See Figure 10 for the adjustment location.
Trigger Center