HP 4935A, Руководство по эксплуатации и обслуживанию

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Operation
4935A TRANSMISSION TEST SET
OUTPUT
IMPULSE NOISE RECEIVER
a. Press key to select IMPULSE NOISE.
b .
Press DISPLAY TRMT-RCV key to display the received signal. RCV light will be on.
d.
Press FILTER key to select the appropriate filter.
Use STEP UP, STEP DOWN and keys to adjust the level of the LOW threshold
shown in the left display. The LOW threshold may be set at any value between 30 and
109
Note: Err 8 indicates the threshold is set out of limits. See paragraph 3-6 for limits.
Press PERIOD key to set the time of the test to 5 MIN, 15 MIN, 60 MIN or NON-STOP.
Press START-RESET key to start the test. The CNTNG LED by the right display will go
on to indicate that the test is in progress. Note that you can see how many counts have
been accumulated at each threshold by pressing DISPLAY key. When NON-STOP is
selected, STOP must be pressed to stop counting.
The left display shows threshold or minutes; the right display shows the number
for the threshold selected.
Note: The 1010 Hz notch filter is automatically used when the C Message or 3 flat filter is selected, it
is not used for the other filters.
Note: A minus sign in the counts display indicates that the tone has dropped below -46 for more than
1 during the test. Tone dropout could cause invalid count totals.
Figure 3-2. Measurements (Continued)
3-13