Prism
Operation Manual Issue 2.00
Page 6.39
6.5.1.
Run to Log (menu 5.1.)
Before running the Channel Checker to Log, it is advisable to use sub-menu 5.2. to
verify initial reception of an error-free data pattern as described in the next section.
When this has been verified, logging can begin by entering sub-menu 5.1.
On entering this mode, the display shows the following:
000# 000:00:10.4
Locked on seq
The counting timecode in the upper right shows the time since the logging was started,
and the number in the upper left shows how many errors have been detected so far, in
this case none.
The message on the bottom line indicates that the PRS data pattern has been
successfully identified at the DSA-1's input. If all is not well, you may have some other
message, most likely reporting that the Generator mode is incorrectly set or that the
input is unlocked. If you have a problem like this, use sub-menu 5.2. to solve it before
you recommence logging.
Once the test pattern is correctly identified, any subsequent error or failure results in
an 'Event' being stored in the Results Log and the Event count in the top left-hand
corner being incremented. A description of the Event appears on the bottom line of the
display. If it is a long-term Event, such as loss of carrier lock or loss of the PRS data,
the message remains for as long as the condition persists. If the Event is transient,
such as a sample data error, it is reported momentarily after which the 'Locked on seq'
message returns.
The [EDIT/CLEAR] key clears the Event count to zero, restarts the timer, and deletes
the Results Log back to the Channel Check Item Marker. This effectively recommences
the Channel Check logging operation. Left to itself, the timer wraps to zero after 1000
hours.
The Channel Check display mode described above is called 'Summary' mode, since it
shows how many Events have been logged, how long the test has been running, and
the current fault status. An alternative display mode is available in Channel Check
mode, which can be entered by pressing the [ENTER/NEXT] key. In this display mode
(the 'Event Viewer' mode), a list of all Events so far logged can be scrolled through
using the [<] and [>] keys. An Event is shown like this in Event Viewer mode:
005. 000:29:09.2
* CARRIER FAIL
