Promax US TV EXPLORER II, User Manual

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USER’S MANUAL. US TV EXPLORER II
01/2008 Page 67
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NOTE
The transmission quality is visualized in a qualitative way using a color range for the
symbol density concentrated in a certain area. This color coding goes from black (no
symbols) to red (maximum density), and runs from blue to yellow in ascending order.
A greater dispersion of the symbols indicates greater level of noise or worse signal
quality.
If concentration of symbols or noise appears is indicative of good carrier/noise ratio or
absence of problems as phase noise, etc.,.
5.15.3 DVB-S/S2 (QPSK/8PSK) signal
Go to the UTILITIES menu by pressing the [22] key, and then select the
CONSTELLATION option.
The modulation type: DVB-S ( QPSK ) or DVB-S2 ( 8PSK ) is showed on screen.
Next, the frequency and channel number corresponding to the channel plan selected as
well as the satellite downlink frequency. Finally, the satellite name and orbital position
are stated.
Figure 47.- Constellation Diagram. DVB-S ( QPSK ) signal.
The US TV EXPLORER II also includes, a ZOOM function to enlarge graphic
representation over one single quadrant. Select the SCROLL option to move the focus
over the whole viewing area using arrow cursors [6] key, CLEAR option to reset
the graph screen or SHARP option to increase the image clearness over a range from 0
(minimum visual persistence) to 16 (maximum visual persistence).