Adjustment Procedures
TDS 684A, TDS 744A, & TDS 784A Service Manual 5–23
HPress the main-menu button EXECUTE; then press the side-menu
button Ok Confirm Run Test.
b. Make the contrast adjustment:
HLocate R404. It is one of the adjustments on the left side of the
instrument located just ahead of the fan. It is the fifth adjustment
from the fan.
HMonitor the luminance at center screen using a J16 photometer and a
luminance probe.
HAdjust R404 (CONTRAST) for a reading of 40 foot lamberts.
NOTE. The adjustments for contrast and brightness interact with each other.
5. Restore the oscilloscope to normal operation:
a. Restore the dip switch to the settings that follow:
Switch No. 1 2 3 4 5 6 7 8
Open X
Closed X X X X X X X
b. Power off the oscilloscope.
c. See Removal and Installation Procedures in Section 6 to reinstall the
cabinet and other modules removed in step 1.