Promax PRODIG-3 Manual Del Usaurio página 118

B) Terrestrial band, digital carrier
Both measurements are done with an average detector (230 kHz) and the same
corrections are introduced on them (bandwidth corrections).
C) Satellite band, analogue carrier
Carrier level is measured using a quasi-peak detector (4 MHz BW). Noise level is
measured with an average detector (230 kHz) and corrected to refer it to channel
bandwidth.
D) Satellite band, digital carrier
Equivalent to case B but now using the 4 MHz BW filter.
On selecting the Carrier / Noise measurement mode the screen displays the
following information:
As well as the video carrier / noise level ratio (C/N) (40.1 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
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
Page 42
0 10
168.25 MHz
FREQ:
S10
CH:
Figure 21.- Carrier-to-noise ratio measurement (C/N).
[13] key, the NOISE cursor is automatically positioned to a side
USER'S MANUAL. PRODIG-3
20 30 40
LEVEL: 79.2 dBµV
» C/N: 40.1
V/A: 16.2
dB
dB
[13].
03/2008