Tektronix 784A Graphics Tablet User Manual


 
Performance Tests
4–38
TDS 684A, TDS 744A, & TDS 784A Service Manual
STOP. DO NOT use the vertical position knob to reposition any channel while
doing this check. To do so invalidates the test.
1. Install the test hookup and preset the instrument controls:
a. Initialize the front panel:
H Press save/recall SETUP.
H Press the main-menu button Recall Factory Setup.
H Press the side-menu button OK Confirm Factory Init.
b. Modify the initialized front-panel control settings:
H Do not adjust the vertical position of any channel during this
procedure.
H Set the horizontal SCALE to 500 ps.
H Press SHIFT; then press ACQUIRE MENU.
H Press the main-menu button Mode, and then press the side-menu
button Average 16.
c. Hook up the test-signal source:
H Connect, through a 50 W precision coaxial cable followed by a 50 W
termination, the sine wave output of a medium-frequency sine wave
generator to a dual-input coupler. See Figure 4–9.
H Connect the coupler to both CH 1 and CH 2. See Figure 4–9.
Medium
Frequency Sine
Wave Generator
Dual Input
Coupler
Digitizing Oscilloscope
50 W Terminator
Output
Figure 4–9: Initial Test Hookup