Spectral Menu

Selecting the spectrum representation

By pressing this button, the represented frequency range can be defined per scale unit. The following settings are possible:

Setting

SAT operation

TV operation

Return path op-

RADIO opera-

 

 

 

 

 

eration

tion

 

Span/DIV

BW

Span/DIV

BW

Span/DIV

BW

 

 

 

 

 

 

 

 

 

large

100 MHz

8 MHz

20 MHz

1 MHz

-------

-----

2 MHz

 

 

 

 

 

 

 

med.

20 MHz

1 MHz

5 MHz

1 MHz

5 MHz

1 MHz

No selection

 

 

 

 

 

 

 

possible

small

5 MHz

1 MHz

1 MHz

200 KHz

1 MHz

200 K

BW 200 KHz

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

full

--------

-------

100 MHz

8 MHz

-----

-----

 

 

 

 

 

 

 

 

 

ANALOG marker

marker ana.￿

The marker can be used or level measurements of analogue carriers in repre- sented spectrum on the screen; here, the marker is placed on the carrier. A yellow triangle in the screen shows the position of the marker. With the cursor buttons, ◄►, the position of the marker can be determined. The frequency and level dis- play of the marker appears on the upper margin on the screen. The level difference (C-M) to the white marker (carrier) is displayed on the lower margin of the screen.

DIGITAL marker

marker dig.￿

Press the same softkey. The upper display changes from A to D (digital measure- ment). With the cursor buttons ◄►, the position of the marker can be set. The fre- quency and level display of the marker appear on the upper margin of the screen.

The level difference (C-M) to the while market (carrier) is displayed in the lower margin of the screen.

For the establishment of digital levels, the MSK 33 calculates a correction value, which is represented by a thin line under he yellow marker,. This value is influ- enced by the respective set spectrum measurement bandwidth (see below) and the symbol rate.

Therefore, observe the correct setting of the symbol rate in the TV and Sat menu!

For DVB-T, the appropriate channel bandwidth (6, 7 or 8 MHz is set in the TV menu.

The scale on the left margin of the screen serves for orientation in the digital opera- ￿ tion. The level of a digital carrier can only be determined with the white or yellow

marker!

C/N measurement of analogue signals in Sat operation

The spectrum menu is opened in the setting, analogue reception. The yellow marker is shifted between the two carriers or in a frequency gap. The C/N meas- urement is carried out in medium or small span.

marker dig.￿

The softkey (yellow marker) must display the setting „dig.“

For noise bandwidth matching, the symbol rate (for DVB-T chBW) set in the SAT or TV menu is used. It must have been set for the C/N measurement in the SAT range to 27.5 MS and in the TV range to 6.9 MS (at DVB-T to7 or 8 MHZ).

Carry out the C/N measurement for the satellite reception directly behind the LNB. For systems with cable slope, the measurement result can be incorrect, if the C/N

measurement occurs for subscriber connection.

The C/N value is displayed now in the right-hand corner (C- M) on the TFT display.

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DreamGEAR MSK 33 manual Marker ana, Marker dig