Spectrum DSP M2 User Manual page 48

Approximate specifications of the Spectrum DSP:
The following specifications are for the Spectrum M2 version 1.0 with
firmware 1.00e.
Because this is a software-defined device and due to ongoing
modifications/improvements
specifications continue to improve!
IQ sensitivity for 10dB S/N, CCITT filtering, taken at 28.3 MHz:
•
Frequency Translation enabled: Better than -111 dBm (0.6uV) in a 2.3 kHz
•
bandwidth, better than -126 dBm (0.11uV) in a 300 Hz bandwidth
Frequency Translation Disabled: Better than -108 dBm (0.89uV) in a 2.3 kHz
•
bandwidth, better than -120 dBm (0.22uV) in a 300 Hz bandwidth
The above specifications are for a receiver on which the published
sensitivity modifications are performed.
Frequency coverage: Receiver/Transceiver dependent
•
Spectral Display Modes:
•
◦ Spectrum Scope: This is a spectrum analyzer with the vertical divisions
representing user-definable amplitude variations of 5, 7.5, 10, 15, 20, 1 S-Unit
(6dB), 2 S-Units (12dB) or 3 S-Units). The baseline ("reference level") of the
analyzer is automatically adjusted so that the signals within the displayed passband
best-fit the dynamic range selected by the user-selected dB/division. A graticule
along the bottom of the display indicates the approximate frequency of the signal
being displayed over a width of +/- 96 kHz. (192 kHz total.)
◦ Waterfall Display: As with the spectrum scope, the frequency is displayed along
the "x" axis but the signal strength is implied by the displayed color. The newest
signals are displayed along the bottom of the screen, but as new readings arrive,
the representations of the older signals are shifted upwards giving an ephemeral
time record of recent activity on nearby frequencies. There are several options for
color "palettes" that range from simple grayscale to "cold-hot" to "rainbow" to
represent weak to strong signals.
◦ There is also a "Magnify" or Zoom mode for both the Spectrum Scope and Waterfall
Display mode that provides x32 magnification, reducing the visible spectral width
from 192KHz to just +/- 3 kHz (6 kHz total).
◦ Both the Spectrum Scope and Waterfall Display are highly configurable. It is
possible to disable one or both spectral display modes if desired.
Large-signal handling capability: Continuous "Clip Warning" occurs above
•
approximately
approximately -18 dBm for signals +/- the local oscillator frequency and higher for
signals outside this range.
Spectrum DSP M2 User Manual V1.1
of
-28 dBm and actual A/D clipping and distortion occurs at and above
the software
P 48
and hardware, the