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
62
Noise squelch determines the level of noise in the received demodulated
audio above which the squelch will mute the receiver. This is particularly useful
for the FM mode, where there is a considerable level of noise in the absence
of a useful signal. The current Noise content value is also shown next to the
corresponding control.
Voice squelch determines the contents of voice frequencies in the spectrum of
the demodulated audio. If lower than the preset threshold, the receiver will be
muted. The voice frequencies content of the currently received signal is also
shown next to the corresponding control.
CTCSS (Continuous Tone Coded Squelch System) defines a particular
CTCSS code which, when received, will open the squelch. The currently
received CTCSS code is shown in the demodulator spectrum display. A
question mark is shown if there is no known CTCSS code currently received.
DCS (Digital Control Squelch, also known as Continuous Digital Controlled
Squelch System or CDCSS) specifies a particular DCS code which will open
the squelch. The R button serves to indicate a reverse code, to comply with
systems which transmit the DCS code in reverse. A question mark is shown if
there is no known DCS code currently received.
The Level squelch can operate simultaneously with any of other types of
squelch. If the Level squelch is selected together with any other then both
selected conditions must be satisfied at the same time for the squelch to open
("and" condition).
The Noise, Voice, CTCSS and DCS squelch modes are mutually exclusive –
only one can be active at a time.
To adjust the level squelch control, first tune to an unoccupied frequency that
produces only noise. Increase the squelch until the receiver is muted. You will
see the red-colored segment of the S-meter growing until it gets higher than
the current S-meter value. At that moment the receiver will be muted and the
word “squelched” will be displayed on the S-meter. Add a few dB extra to
allow a margin for background noise fluctuation on the band. Now when you
tune to an occupied frequency, if its signal strength is higher than the squelch
level, the receiver will be unmuted.
To adjust the noise squelch control, first tune to an unoccupied frequency that
produces only noise. Note the Noise content value indicated next to the
associated control. Then tune to an occupied frequency where there is a
useful signal, and note the noise content value again. Then set the noise