Spectral Menu

C/N measurement of digital signals in Sat operation

marker dig.￿

The spectrum menu is opened in the setting, digital reception. The yellow marker is moved between two carriers or in frequency gaps. The C/N measurement is car- ried out in medium or small span.

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

For noise bandwidth matching, the symbol rate set in the SAT or TV menu (for DVB-T the chBW) 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 to 7 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.

For analogue or digital C/N measurements, the symbol rate in the SAT MEASURE menu must be set to 27.5 MS. The noise measurement bandwidth is based on 27.5 MHz.

Cross-polarisation measurement on signals in SAT operation

zoom marker

Possibly, a transponder of the other polarisation planes is recognised as a small knob between the two transponders for a poor aligned LNB. Place the yellow marker on this knob. The display C-M represents the cross-polarisation spacing. Measure in digital reception mode for digital carriers and in analogue reception mode for analogue carriers. The marker is also to be set to analogue or digital ac- cording to the reception mode.

This function allows an enlargement of the spectrum on the yellow marker position. If you press this button, the frequency of the yellow marker is transmitted to the white carrier marker and zoomed to „small span.“ After exiting the spectrum analy- sis, the frequency is also adopted in the picture representation.

max off ►

￿

By pressing this button, the spectrum is switched to „Max hold.“ Pressing the but- ton again switches it back to clear write.

If you have an unit with a graphic card (MSK33G, MSK33Q, MSK33M), you can also printout the spectrum of the spectrum analysis. To do so, press the button „COPY“ in the spectrum analysis and then the softkey button, „print data“.

After the printout, return to the original measuring job by pressing the button „COPY“ once more.

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DreamGEAR MSK 33 manual Measurement of digital signals in Sat operation, Zoom marker, Max off