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
86
If HF sensitivity appears poor, please first ensure that the attenuator is
disabled.
Preamplifier
For the VHF/UHF/SHF section of the receiver, the Preamp button engages a
low noise preamplifier, which adds approx 10 dB of amplification to the front-
end, and so increases sensitivity.
Please note that the actions of both the attenuator and preamplifier are
compensated for by the S-meter. This means that the S-meter always
displays the actual signal strength at the antenna input, within the
available measurement range.
S-meter
The WiNRADiO Excelsior receiver is equipped with a very sensitive and
selective Signal Strength Meter (S-meter) which makes it possible to
measure peak or RMS signal level in dBm, µV or S-units, within the
demodulator filter passband. The measurement units are selected by
appropriately marked buttons at the bottom of the display.
The S-meter also shows the currently selected value of the squelch (the red
section at the bottom side of the scale) when the squelch is enabled. When the
signal strength falls under the squelch level (i.e. the needle falls in the red
region and turns red also), the receiver audio will be muted and the word
“Squelched” will appear inside the S-meter.
The squelch value is always indicated in dBm (even if the signal strength is
displayed in S-units or microvolts).