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ENGLISH
TV & SAT Level Meter MTD 120
User Manual
4.9.2.10.- C/N setup
To measure C/N the MTD 120 offers two different modes in TV mode:
C/N (Auto)
The MTD 120 defines automatically the frequency where noise level is measured, according with:
f
noise
= f
tuning
- 1/2 Channel BW
C/N (Reference noise)
The user defines the frequency where noise level is measured (by means of the Reference noise
function). This frequency will be used to measure noise level for all channels.
To select C/N mode, access the TV mode functions menu, press keys
[6] to select the C/N setup function and press key ENTER
[5] to activate it. The monitor will show a screen labelled C/N SETUP displaying the two available options (as well as the Exit option). Press
keys
[6] to select the mode you require, then press key ENTER [5] to activate it.
4.9.2.11.- Channel Bandwidth (Channel BW)
To measure the power and C/N ratio of digital channels, as well as the C/N ratio of satellite band channels, you first need to define the
channel bandwidth.
To modify the bandwidth access the TV mode functions menu and select the Channel BW function, press key ENTER [5] to activate it.
The CHANNEL BANDWIDTH screen will be displayed. To alter the bandwidth value press key SHIFT [31], the bandwidth will disappear and,
using the keyboard, you will be able to enter the new digital channel bandwidth in MHz and with two decimals.
4.9.2.12.- LNB Local Oscillator Frequency (Lnb local osc)
This option only affects reception of satellite band signals when using the channel tuning mode. This function defines the LNB local
oscillator frequency used in the installation where the MTD 120 has been connected. Given that the MTD 120 satellite channel tables have
been defined in the Ku band and the MTD 120 tunes in IF (like all satellite receivers) the LNB local oscillator frequency has to be defined to
correctly tune the channel mode.
To modify this parameter access the TV mode functions menu (satellite band), press keys
[6] to select the Lnb local osc function
and press key ENTER [5] to activate it. The monitor will show a screen labelled LNB LOCAL OSCILLATOR displaying the current value of
the LNB local oscillator frequency. To alter this value press key SHIFT [31], the current value will disappear and the new value can now be
entered using the keyboard.
The frequency of the LNB local oscillator is expressed in MHz, with 5 figures for the whole part, a decimal point and a decimal figure
(which acts as confirmation). For example, to select 9 GHz the number 9000.0 has to be entered. Values must be defined between 8000.0
and 12000.0.
4.9.2.13.- Video Polarity
This option affects reception of SAT (satellite) band signals. It allows selection of either negative and positive video polarity.
To modify the polarity access the TV mode functions menu (satellite band), select the Video Polarity function, and press key ENTER [5]
to activate it. The monitor will show a screen labelled POLARITY displaying two possibilities: Positive Video and Negative Video. Pressing
keys
[6] mark the option you require and finally press key ENTER [5] to activate it.
4.9.2.14.- NICAM Channel
Use this function to verify NICAM sound modulations in stereo and dual, you can also select the sound channel coming over the speaker.
To change the decoded channel access the TV mode functions menu, select the Nicam channel function, and press key ENTER [5] to
activate it. The monitor will show a screen labelled NICAM offering two possibilities: Channel A and Channel B. Press keys
[6] to
select the desired option and finally press key ENTER [5] to activate it.
4.9.2.15.- Search Level
Use this function to modify the threshold level of the automatic station search. To change the level place the cursor on the Search level
field and press key ENTER [5]. The monitor will display a window showing the current value of the search level, to alter it press key SHIFT
[31] and enter the new value on the keyboard. Confirmation is automatic on entering the second digit.
4.9.2.16.- Teletext
When the Teletext function is selected, Teletext information appears on the monitor if a transmitter with this information is tuned. The first
page to appear on the screen is always page 100. If Teletext data is received, a counter located on the upper edge of the screen indicates the
page that is being processed. To change active page press key SHIFT [31], and introduce the new number using the numeric keyboard (third
digit acts as confirmation).
If the page requested is not included in the Teletext service of the transmitter, the search will continue indefinitely. In such a situation the
user can halt the search process, either by entering a new page number or by exiting the Teletext function pushing any control relative to
another function.
