3.3.3.2.1.3.1.- Channel BW
When this option is pressed, a small window opens on top of the previous window, displaying
the value of the video bandwidth which will be taken into account when automatically
compensating the noise (we recommend 5 MHz for this measurement). As the user turns the
rotating knob, the different options will appear. To select a value, press this knob.
3.3.3.2.1.4.- Referenced C/N
When this function is selected, the video signal automatically disappears from the
screen. This is because the equipment has to carry out the noise measurement in
the reference frequency. Because of this, the
button is not enabled.
The window that appears when this function is selected is the following:
Figura 65.-
Referenced C/N measurement. Channel tuning
Figure 66.-
Referenced C/N measurement. Frequency tuning
If in channel tuning mode, you will be able to see the channel with the carrier that is being used
to carry out the level measurement. As has already been explained, if the equipment is in
frequency tuning mode, the level measurement will be carried out in the frequency that the user
has tuned, and so it will be the user’s responsibility to make sure that this frequency
corresponds to the real channel carrier.
To carry out this measurement, it is necessary to indicate two parameters; the
frequency
at
Frequency at which the
noise level is measured.
Tuned
frequency
Channel bandwidth
C/N measurement
Tuned channel
Channel bandwidth
C/N measurement
Selected channel plan
Frequency at which the
noise level is measured.
Multimetter FSM 500
Ref. 5903
60
