Fluke 635 User Manual page 53

Care must be taken if the readings are taken from a DSX monitor jack
with the RX INPUT key set to DSX MON. In that case, the isolation
resistors will cause the level reading to be approximately –20 dB
below the actual line level. In order to determine the actual line level
from a DSX monitor jack, 20 dB must be added to the reading
displayed on the display screen (if the readings are in dBDSX). If the
readings have been converted to peak-to-peak volts, multiply by 10 in
order to get a true line-level measurement at a DSX monitor jack.
8. Proceed as follows to observe parameters associated with specific DS0s.
a. Use the SIGNALING TYPE key to select the type of signaling used
on the T1 facility (robbed bit, CCIS, or E-Bit).
b. Use the CHANNEL UP/DOWN keys to select the DS0 to be
monitored.
9. Observe the signaling bits associated with the selected DS0. A and B
signaling bits will be displayed for D4- or SLC96-framed signals. A, B, C,
and D signaling bits will be displayed for ESF- framed signals.
10. Observe the Data Bits LEDs, which will indicate the 1 or 0 state of the
data bits associated with the selected DS0.
11. The demodulated audio signal from the selected DS0 may be monitored
using the speaker and adjusted using the volume control. For your
convenience, a headphone jack is provided.
12. Record the frequency and level of a test tone present on the selected DS0.
a. Use the RESULTS keys to observe the frequency of the test signal in
hertz.
Use the RESULTS keys to observe the level of the test tone in dBm.
b.
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Operation
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