Advanced Instruments 4250, User Manual

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7. Display/Print Test
This test is a simple check of the display and printer. On entry, a series
of characters should scroll across the display (and a single line of the
same characters should print out on the printer). The characters dis-
played have been chosen to illuminate every dot in the character matrix.
This makes it possible to distinguish any dots that no longer work, on
the printer as well as the display.
Press
STOP to exit to the test menu.
8. Beeper Test
This test exercises the beeper.
1. On entry, “ [on] beeper [off] ” is displayed. Press the < key to
cause the beeper to beep repeatedly; press the > key to stop the
beeper.
2. Press STOP to exit to the test menu.
9. Keypad Test
This test enables checking each key on the keypad, as well as the lamps
of each illuminated key. As each key is pressed, its name should be dis-
played and the lamp of each illuminated key should light.
Press the
STOP key twice to exit to the test.
10. Head Up/Down Test
This test enables selectively lowering and raising the operating head. It
may be used to check the operation of the head motor drive, to prime
and drain the heat transfer fluid pump, and to check for obstructions in
the fluid system.
CAUTION To protect the sample probe, place a sample tube in the
freezing chamber before running this test.
1. On entry, “ [START] Test [STOP] ” is displayed. Press START to
continuously cycle the operating head down and up.
Advanced
®
Cryoscope Model 4250 User’s Guide
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