Performance Tests
TDS 684A, TDS 744A, & TDS 784A Service Manual 4–45
1. Install the test hookup and preset the instrument controls:
a. Initialize the instrument:
HPress save/recall SETUP.
HPress the main-menu button Recall Factory Setup.
HPress the side-menu button OK Confirm Factory Init.
b. Modify the default setup:
HPress VERTICAL MENU.
HPress the main-menu button Coupling; then press the side-menu
button to select 50 coupling.
HSet the horizontal SCALE to 10 ns on the TDS 684A and 12.5 ns on
the TDS 7XXA.
c. Hook up the test-signal source: Connect the output of a
medium-frequency leveled sine wave generator (Item 11) to CH 1. Do
this through a 50 W precision coaxial cable, followed by a 10X
attenuator. See Figure 4–13.
50 Coaxial Cable
Medium-Frequency
Sine Wave Generator Digitizing Oscilloscope
Output
10X Attenuator
Figure 4–13: Initial Test Hookup
2. Confirm the trigger system is within time-accuracy limits for pulse-glitch or
pulse-width triggering (Horizontal Scale ≤1 s):
a. Display the test signal: Set the output of the sine wave generator for a
100 MHz, five-division sine wave on screen. Press SET LEVEL TO
50%.