Field View measurement mode views and analyzes ingress and distortion
on the upstream path (return path) as captured at a node return at the
headend or hub. It identifies the frequency at which ingress occurs and
displays the level value.
The Field View measurement mode graph continuously updates the spectrum
from the PathTrak or Phasor System as each frequency is measured. This
forms a wavy measurement line (trace) across the entire frequency range.
When excessive ingress noise occurs at a specific frequency, the measurement
line develops a peak on the graph.
The frequency range in this mode is selectable by the PathTrak or Phasor
user, with the start and stop frequencies indicated on the horizontal
bar at the bottom of the screen. As you move the marker (the thin vertical
bar) across the frequency range with the left or right arrow key, the
numeric frequency and level value is displayed below the graph. Use the
up and down arrow keys to adjust the reference level in 1dB increments.
Softkeys
Four softkeys on the Field View screen provide the following options:
FILE
Save or print a completed test. You also can open an existing Field View
measurement file to compare previously collected data. Use the arrow keys
to choose the menu item you prefer and press ENTER to make your
selection.
VIEW
Use the arrow keys to choose the menu item you prefer and press ENTER
to make your selection.
Select Auto Reference to automatically view measurement results
in the best reference setting on the graph (Keystroke shortcut: SHIFT
9). NOTE: For best reference setting results you may have to select
the Auto Reference button more than once (up to three times).
Select 5 dB/div or 10 dB/div to adjust the vertical resolution
of the graph for the best viewing.
Select (or deselect) Peak Hold to turn on and off the Peak Hold
function, which persists the highest level trace at each frequency for
improved noise isolation. NOTE: It is recommended to use the Peak
hold option to verify the Return Signal Generator Field View gain/loss.
Select Reset to manually reset the Peak Hold function.
Select Spectrum to display the local Upstream Spectrum measurement
mode.
Select Pause to suspend measurement updates (Keystroke shortcut:
SHIFT 8).
SETTINGS
Use the arrow keys to select Broadcast Nodes, All Nodes,
RSG setup, RSG on/off or Telemetry Frequency and
press ENTER to make your selection.
Select Broadcast Nodes to view only the broadcast nodes in the PathTrak
or Phasor system or select All Nodes to view all available nodes
on the HCU you have access to. NOTE: If the node you want to view
is not being broadcast, contact the PathTrak or Phasor system administrator
to request activation. You must provide the PathTrak or Phasor system
administrator with the unique identifier (UID) of the requested node.
The UID number is located on the bottom-left of the screen. (See the Help
section entitled "Configuring Field View")
Select RSG setup to set the level and frequency of the Return Signal
Generator. To set the Return Signal Generator frequency see the Help section
entitled "Configuring Field View".
Select RSG on/off to turn on or off the Return Signal Generator.
NOTE: To enable the Return Signal Generator the setting of the
receiving telemetry frequency must be 200 MHz or above. The Return
Signal Generator CW output is a pulsing signal if a telemetry carrier
is not present.
Select Telemetry Frequency to set the telemetry frequency of the
return monitoring system modem. Set the telemetry frequency between 50
MHz and 1000 MHz by using the numeric keypad and then press
the ENTER key. NOTE: The telemetry frequency must be set
to match the frequency at which the headend modem is broadcasting data.
Default is 53 MHz. (See the Help section entitled "Configuring Field
View")