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5.7.2 Changing the Sweep Direction
The sweep direction can be selected using the “Sweep Receiver”
setup screen as described earlier. You can also change directions
while you are viewing the Sweep response using the left and right
arrows. Press the left arrow to select Reverse and the right arrow to
select Forward.
5.7.3 Reverse Noise Feature
There are two key requirements to ensure proper operation of the
reverse path. One is that the amplifiers be properly aligned to ensure
that the digital signals are not clipped or compressed. This align-
ment is performed using the reverse sweep procedure. The other
requirement is that a proper carrier-to-noise and carrier-to-ingress
ratio be maintained. The Reverse Noise feature enables a quick
swept noise test at the reverse sweep point frequencies. Simply press
the “Noise” soft key while sweeping reverse, and the display will
change to a noise response indicating the noise level at the same
frequencies. This provides for simple, comprehensive testing of both
amplifier alignment and reverse noise in the headend.
5.7.4 Telemetry Level Indicator
The level of the telemetry carrier is displayed in the lower right hand
corner of the sweep screen. This is the Forward telemetry carrier
level during a forward sweep, and the Reverse telemetry carrier level
during a reverse sweep. The unit in which this is displayed depends
Summary of Contents for 3SR
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