VeEX VePal CX350, User Manual

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Starting from a drop point nearest to the signal source, for example, a Headend office, a Sweep operation measures the signal levels across the bandwidth with predefined
check points in a Sweep table. The measurement is kept as a reference. Move the test set to the next drop point away from the first one, take the same measurement and
compare with the reference measurement. Ideally, the signal of each check point should be relatively less or more, proportionate to the reference signal.
The following Sweep Operations are available under the Sweep Operations menu:
Return Path Sweep:
This function verifies the frequency response, tilt and proper operation of the amplifiers.
Take a measurement by the sweep receiver in the Headend while sweep tones are inserted at point 2; the closest point to the Headend. Save this measurement as
reference. Move and insert sweep tones at points 4, 5, 6, and 7, compare results and verify the frequency response and tilt at each point is relatively flat (refer to the
graphic titled " HFC Test Points - Return Path ").
Return Path Sweep
The Return Path Sweep operation on CX350 depends on the test mode selection of either Controller or Responder, which can be selected under SETUP, Main
Menu. The CX350 operates as a return path signal generator unit if Controller is selected, and a measurement unit if Responder is selected.
In Service Sweep:
This is a non service interrupting forward path sweep feature.
In the Analog spectrum, sweep can be performed by inserting tones within the analog TV channels or un-used bands - a sweep tone generator is then required at the
Headend. In an all-digital HFC system, tone insertion between channels is not possible, therefore In Service Sweep (ISS) is the preferred solution. ISS measures
existing channels and makes a comparison.
Forward Path Sweep Insertion Points
The current channel table is used. The CX350 measures the in-service analog and digital channels to obtain the frequency response of the HFC networks.
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7.8.3 Remote Operations
Overview:
Remote Operations allow fast spectrum analysis with high speed Internet communication that is not possible with the slow and old-style telemetry system. There is easy
Internet connection through existing HFC network with built-in Cable Modem, USB WiFi adaptor, USB 3G mobile data card, or built-in 10/100-T Ethernet port. This function
also offers powerful all-in-one features such as remote return path spectrum analysis, remote return path QAM analysis with integrated QAM generator supporting QAM16,
64, 128 and 256 modulations, remote return path multi-port ingress monitor, and remote return path alignment with integrated CW generator.
The following functions are available under the Remote Operations menu:
Remote View:
An optional feature to allow remote viewing of other VeEX CX devices.
IGM Scan Monitor:
To view a CX180R-IGM, the return path monitor system, current scanning spectrum.
It is possible to conduct remote operations between a CX350 field unit to a CX180R Return Path Monitoring System. It is also possible to conduct Remote View between a
CX350 field unit (acting as Controller) and a far end CX380 unit (acting as Responder) that is typically located at the headend.
For operations between CX350 field unit and CX180R:
The communication between these two units is done via Internet connection made through the following options:
CX350 e-Manual D07-00-037 RevC01 Page 44 of 81