Promax Promax TV EXPLORER HD ISDB-Tb, Manual

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USER’S MANUAL. TV EXPLORER HD ISDB-T/T
B
Page 54 11/2010
As well as the video carrier / noise level ratio ( C/N ) (41.0 dB in previous figure), the
frequency or channel (depending on the tuning mode selected) and the level of the video
carrier and video/audio ratio are also shown. When representing the spectrum by means
of pressing [13] key, the NOISE cursor is automatically positioned to a side of the
carrier tuned. That is, the cursor will indicate the point where the value of the noise is
lower, whenever the C/N (AUTO) option is selected from the PREFERENCES [22]
menu. If the C/N (MANUAL) option has been activated the frequency where noise level
will be measured will correspond to the position of the vertical discontinuous green-
coloured cursor that appears in the spectrum graph [13].
In order to modify this frequency, press the measurement configuration
[17] key, to accede to the CONFIGURATION menu. By turning the rotary selector
[1], locate the NOISE cursor on the position of the marker using
NOISE FREQ. TO
MARKER
option (see section “ 5.16.1 Markers ”) or directly enter the value of the new
noise frequency by means of
NOISE FREQ
option.
Figure 28.- NOISE cursor. C/N (MANUAL).
When measuring channels in the satellite band or digital channels, to measure the
C/N ratio correctly, the bandwidth of the channel must be defined previously, using the
Channel BW option on the Measurements Configuration menu that appears when
pressing the [17] key.