User's Manual
Table Of Contents
- Table of Contents
- Introduction
- The Hardware
- Installation
- Getting Started
- Inside the Excelsior
- Resizing the Application Window
- Drop-Down Menu Controls
- Tuning the Excelsior
- Receiver Selection
- Mode Selection
- Function Tabs
- Spectrum Scopes
- Recording Functions
- Attenuator
- Preamplifier
- S-meter
- Top Menu Bar
- File
- Options
- Auto-mute RX not in focus
- Enable second RX
- Filter Length
- Front Panel LED
- Display Offset
- Time
- Keyboard Shortcuts
- VSC Set-up
- Audio Buffering
- AMS Capture Range
- Audio Output
- Show Measurements
- Show Data Rates
- Of particular interest to many users will be the CPU load (excessive CPU load may cause sluggish behaviour or freezing of the computer), and Audio latency. Apart from DDC bandwidth, CPU load may be minimized by reducing the Demodulator filter length (...
- Note: When measuring sensitivity using SINAD, it is very important that the Audio Filter is enabled and the cut-off frequencies (and for FM measurements, also the de-emphasis) are set according to the specified test conditions. Proper audio filtering ...
- Show Waterfall Timestamps
- Calibration
- Hand-Off Receiver
- Color scheme
- Restore factory defaults
- Memory
- Scheduler
- Scanner
- Logger
- Plugins
- Power Switch
- Date and Time Display
- Appendix A – SDR and DDC Primer
- Appendix B – Troubleshooting
- Appendix C – USB Interface Diagnostics
- Appendix D – Dealing with Interference
- Appendix E – G39DDCi PCIe Card Connections
- Appendix F – Waterfall Spectrum Palettes
- Appendix G – Recording File Formats
- Appendix H – Compliance Declarations
- Appendix I – Safety Disposal
WiNRADiO G39DDC User’s Guide
47
Frequency Stepping
Another facility available under the tuning tab is Frequency stepping:
The Step control selects the stepping size. The
following convenient step sizes are available: 1 Hz,
10 Hz, 100 Hz, 1 kHz, 3.125 kHz, 5 kHz, 6.25 kHz, 10
kHz, 12.5 kHz, 25 kHz, 50 kHz, 100 kHz. The left
and right arrow
buttons perform the actual stepping.
Spectrum Centering
The Center button
, next to the stepping controls, centers the
demodulator passband.
Use this button if you have tuned to a station by dragging the filter passband
over its spectrum, and you would like to see this station relocated to the center
of the demodulator spectrum.
AFC (Automatic Frequency Control)
The AFC button
, when engaged, forces the receiver to automatically
adjust its tuning to follow the frequency drift of the received transmission.
While this function is active, the receiver will periodically check the received
signal and correct the frequency in approximately five-second intervals.
This facility is not recommended for LSB and USB modes with voice
modulation.
TTP (Tune to Peak Control)
The Tune to Peak function can be invoked by pressing the TTP button
.
The receiver will tune to the signal peak (provided the peak falls inside the
selected IF bandwidth – the highlighted area of the real-time frequency
spectrum).
Depending on the location of the peak and type of signal, it may take several
seconds for the receiver to tune in accurately, by a successive approximation
process.