Self Test Description - HP 3457A Service Manual

Service 3457A
F L O A T I N G COMMON
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Figure 8-1. Simplified Block Diagram
8-32. SELF TEST DESCRIPTION
8-33. Power ON Sequence
8-34. When the HP 3457A is "turned-on", it automatically performs a self-test t o check the logic of both the
chassis common and floating common sections of the instrument. The areas tested are: the master processor,
(A1 assembly), the slave processor (A2 assembly) and the isolation logic circuitry between the t w o as-
semblies. This test verifies that the instrument is capable of operating. It does not test the measurement ac-
curacy of the instrument.