Idiomas disponibles
Idiomas disponibles
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:
Figure 9.- Carrier-to-noise ratio measurement (Satellite band, analogue signal).
As well as the video carrier / noise level ratio (20.1 dB in previous figure), the
frequency or channel (depending on the tuning mode selected) and the level of the
video carrier and noise level are also shown.
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 function on the TV mode functions menu.
To measure digital channels C/N ratio in Auto mode it is indispensable to tune channel
at its central frequency.
In the case of an analogue terrestrial signal, when C/N (Auto) mode is selected, the
PROLINK-4 performs an in-channel measurement, this involves that C/N value will take
several seconds to stabilize (six seconds at the most). An arrow below the C/N readout
represents the measurement cycle and it is necessary to wait the arrow passes twice on
the same point to guarantee a correct measurement.
Page 36
C /N (AU TO )
20.1 dB
V ID E O C A R R IE R :
F R E Q U E N C Y
= 134 5.5 M Hz
L E VE L
=
N O IS E :
L E VE L
=
C H A N N E L B W
=
USER'S MANUAL. PROLINK-4
64 .1
dBuV
44 .1
dBuV
32 .0
M Hz
IMPORTANT REMARK
IMPORTANT REMARK
02/2003
