RADIXON WR-G35DDC EXCALIBUR ULTRA, User Manual

Page: 67 / 128

WiNRADiO G35DDC User’s Manual
67
Spectrum Scopes
We have already touched on the spectrum scopes in some of the preceding
paragraphs, but there is much more to the WiNRADiO
Excalibur Ultra
spectrum scopes than just the ability to “point-and-click” tune or drag the
demodulator filter passband.
The three spectrum scopes can be considered to be subsets of one another:
The
Wideband spectrum scope is always 30 or 50 MHz wide (this selection
can be made using the Frequency range function located under the top bar
Options menu).
A zoomed-in portion of the wideband spectrum is the DCC spectrum , whose
width can vary from 20 kHz to 32 MHz, selectable in 33 steps (this is
selectable using the
DDC BW control). Finally, the Demodulator spectrum is
a subset of the DDC spectrum, making it possible to inspect the signal with the
highest resolution. The demodulator filter bandwidth (adjustable using the
DEM BW control) is the bandwidth of the last filter and the actual demodulated
signal.
The demodulator spectrum width is the lesser value of 64 kHz and the DDC
bandwidth. The relationship between the selected DDC bandwidth and the
width of the demodulator spectrum is also shown in
Appendix D –
Demodulator Spectrum Width .
The grey shaded area in the wideband spectrum represents the DDC
bandwidth. The grey shaded areas in both the DDC and demodulator
spectrum both represent the currently selected demodulator filter bandwidth.
All three spectrum scopes use similar controls in their graphical user interface,
even though their functionality is different. Let’s have a look at the common
controls first, and leave the specific features of each spectrum scope till last.