Tektronix 371B, Service Manual

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Maintenance
371B Service Manual
4-9
Table 4-2: PowerĆup System Error Messages
Display Description
0/1 (blink) System ROM error (e.g., misinsertion)
0/2 (blink) System RAM error (e.g., bus shorted)
0/3 (blink) Display RAM Read/Write error (e.g., bus shorted)
0/4 (blink) Acquisition RAM Read/Write error (e.g., bus shorted)
0/5 (blink) Flash ROM error
0/99 (blink) Lithium battery low (warning)
LED Check.
This is the first of two extended power-up diagnostic routines. This
test runs when the operator presses the cursor SHIFT button and holds it pressed
when pressing the POWER switch. When the power-up sequence reaches this
test, it displays a logo while it sequentially lights all front-panel LEDs.
. You may have to adjust the NON STORE/STORE/VIEW intensity control
to display the logo.
The operator can follow the lighting sequence to obtain a visual indication that
the LEDs are operating.
When all LEDs have been lit in sequence, the 371B diagnostic software
advances to the display quality check.
Be sure to turn the NON STORE/STORE/VIEW intensity control to a
level that prevents burning the CRT when the display quality test pattern is
displayed.
Display Quality Check.
This is second of two extended power-up diagnostic
routines. When the extended power-up sequence reaches this test, the 371B
displays a test pattern as shown in Figure 4–1. The operator can use this text
pattern as a template to align the display vertically and horizontally using the
display ROTATION screwdriver adjustments. Use these adjustments to position
the display as shown in Figure 4–1.
The NON STORE/STORE/VIEW intensity control adjusts the intensity of the
bright alignment dots. These dots are displayed at the center, outer corners, and
mid-outer lines of the display graticule. The READOUT CURSOR intensity
control adjusts the intensity of the double-line, dotted box.