I
-
Specifications and Test Aids
Cable TV Measurement Specifications and
Characteristics
CSO and CT6 Distortion*
Optimum Input Range
Maximum
CSO/CTB
Range
Manual CSOKTB Resolution
System CSOKTB Resolution
CSO/CTB
Accuracy
Manual composite second order
ICSOl
end composite triple beet
ICTBl
distortions are measured relative to the visual carrier peak and require
momentary disabling of the carrier. Automatic measurements are made
in the channel above the channel selected and assumes that it is
unused. If the analyzer has Option 107, a non-interfering CSO
measurement can be made.
See
Grephst
Input level dependent See
Graphsf
66 to 73
dB
over optimum input range
0.1
dB
1
dB
Input level end measured CSOKTB dependent
-
See graphs
f1.5
dB
to f4.0
dB
over optimum input range
“A preamplifier end preselector filter may be required to achieve specifications.
tOptimum
input range is determined et the time of measurement since a total input power measurement is first done to automatically set the
attenuator.
C/N,
CSO,
and
CTB
Measurements
The following graphs summarize the HP 85721A personality characteristics for
C/N, CSO, and CTB testing on cable TV systems with up to 77 channels and
no amplitude tilt. C/N, CSO, and CTB measurement accuracies and ranges
can be read from the relevant graphs. They depend upon the visual carrier
peak level and the measurement reading and the total power input to the
analyzer. See Chapter 8 for test descriptions for each test.
9-6