Tektronix 684A Graphics Tablet User Manual


 
Performance Tests
TDS 684A, TDS 744A, & TDS 784A Service Manual
4–49
H Connect the output of the DC calibration generator, through a
dual-banana connector followed by a 50 W precision coaxial cable,
to one side of a BNC T connector.
H Connect the Sense output of the generator, through a second
dual-banana connector followed by a 50 W precision coaxial cable,
to other side of the BNC T connector. Now connect the BNC T
connector to CH 1.
b. Initialize the oscilloscope:
H Press save/recall Setup.
H Press the main-menu button Recall Factory Setup.
H Press the side-menu button OK Confirm Factory Init.
2. Confirm Main trigger system is within limits for Trigger-level/Threshold
accuracy:
a. Display the test signal:
H Set the vertical SCALE to 200 mV.
H Press VERTICAL MENU, then press the main-menu button
Position.
H Set vertical position to –3 divisions (press –3, then ENTER, on the
keypad.) The baseline level will move down three divisions. See
Figure 4–16 on page 4–50.
H Press the main-menu button Offset.
H Set vertical offset to +10 volts with the keypad. The baseline level
will move off screen.
H Set the standard output of the DC calibration generator equal to the
offset (+10 volts). The DC test level will appear on screen. See
Figure 4–16.
b. Measure the test signal:
H Press SET LEVEL TO 50%.
H Press TRIGGER MENU.
H Read the measurement results from the readout below the label
Level in the main menu, not the trigger readout in the graticule area.