Robotron G5E User Manual
FCC ID: HNL-G5E Report No. M060140_Cert_G3_External_Receiver
EMC Technologies Report Number: M060140_Cert_G3_External_Receiver
APPENDIX G
User Manual
EMC Technologies Pty Ltd – 57 Assembly Drive, Tullamarine VIC 3043 Australia
www.emctech.com.au
WiNRADiO®
G3xx VHF/UHF Receiver
User’s Guide
WiNRADiO G3XX VHF/UHF Receiver
Published by
WiNRADiO Communications
PO Box 6118, St Kilda Road, Melbourne 3004, Australia
© 2006 WiNRADiO Communications, Melbourne
All rights reserved. No part of this book may be reproduced or transmitted in any form or by any
means without the written permission of the publisher.
Trademarks
WiNRADiO, G3 and Radio Basic are trademarks of WiNRADiO Communications
All other brand and product names are trademarks of their respective owners.
Patents
WiNRADiO technology is protected by US Pat. No. 6,289,207 and other pending US and
international patent applications.
Printed in Australia
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WiNRADiO G3XX User’s Manual
FCC Notice
This equiment has been tested and found to comply with the limits for a Class B digital device,
pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection
against harmful interference in a residential installation. This equipment generates, uses and can
radiate radio frequency energy and, if not installed and used in accordance with the instructions,
may cause harmful interference to radio communications. However, there is no guarantee that
interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment off
and on, the user is encouraged to try to correct the interference by one or more of the following
measures:
• Reorient or relocate the receiving antenna
• Increase the separation between the equipment and the receiver
• Connect the computer into an outlet on a circuit different from that to which the receiver is
connected
• Consult an authorised dealer or an experienced radio/TV technician for help
Caution
To comply with the limits for the Class B digital device, pursuant to Part 15 of the FCC rules, the
WiNRADiO card must be installed in computer equipment certified to comply with the Class B
limits. Only peripherals certified to comply with the Class B limits may be attached to the
computer containing the WiNRADiO receiver. Only original cables and power adapters must be
used. Operation with non-certified cables, power adapters and peripherals may result in
interference to radio and TV reception.
Modifications
Any changes or modifications to the WiNRADiO receiver could void the user's authority to operate
this equipment, as well as void the manufacturer’s warranty.
Limitation of Liability and Remedies
The information published in this book has been compiled from several sources. While every
effort has been made to ensure its accuracy, neither the authors nor the publisher can guarantee
that all information is entirely correct or up-to-date. Furthermore, neither the authors nor the
publisher can take any responsibility for the use of this information or any consequences arising
therefrom. WiNRADiO Communications shall have no liability for any damages due to lost profits,
loss of use or anticipated benefits, or other incidental, special or punitive damages arising from the
use of, or the inability to use, the WiNRADiO receiver, whether arising out of contract, negligence,
tort or under any warranty, even if WiNRADiO Communications has been advised of the possibility
of such damages. In no event shall WiNRADiO Communications ' liability for damages exceed the
amount paid for this product. WiNRADiO Communications neither assumes nor authorises anyone
to assume for it any other liabilities.
Warning
In certain countries or states it may be illegal to monitor certain frequencies. We cannot accept
any responsibility for the consequences of your non-compliance with government regulations. If
you are in doubt about the regulations in your country or state, please contact your nearest radio
communications regulatory authority.
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WiNRADiO G3XX VHF/UHF Receiver
Table of Contents
Table of Contents.................................................................................... 4
Introduction..............................................................................................6
G3XX Receiver Models............................................................................ 7
Installation................................................................................................ 9
System Requirements.......................................................................... 9
Hardware Installation......................................................................... 10
Software Installation........................................................................... 11
Setting up the Sound Card................................................................. 12
Connecting the Antenna .................................................................... 13
Getting Started....................................................................................... 14
Tuning WiNRADiO G3XX.......................................................................16
Manual Frequency Entry....................................................................16
Tuning Knob ...................................................................................... 18
Keyboard Tuning................................................................................ 18
Incremental Tuning Pad.....................................................................19
Tune To Peak ....................................................................................19
AFC (Automatic Frequency Control).................................................. 20
Frequency Stepping...........................................................................20
The Demodulator...................................................................................22
Selecting Demodulation Mode........................................................... 22
Real-time Spectrum Scope................................................................ 23
Setting and Adjusting IF Bandwidth................................................... 25
IF Shift and Passband Tuning ............................................................ 27
Volume Control.................................................................................. 28
Mute Control ...................................................................................... 28
Software AGC....................................................................................29
AF Squelch (Audio Filter Squelch).....................................................30
Notch Filter ........................................................................................ 31
Audio Filter......................................................................................... 33
Noise Blanker..................................................................................... 34
Receiver Incremental Tuning (RIT)....................................................34
Recording and Playback.................................................................... 35
Test and Measurement...................................................................... 38
Demodulator Structure ......................................................................... 40
Other Demodulator Settings .............................................................. 41
Receiver Gain Control........................................................................... 42
AGC................................................................................................... 42
IF Gain Control................................................................................... 43
RF Gain Control................................................................................. 43
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WiNRADiO G3XX User’s Manual
Squelch Control.....................................................................................44
Memory...................................................................................................46
Storing a Frequency into Memory ......................................................46
Recalling a Frequency from Memory..................................................48
Editing Memory ..................................................................................49
Deleting a Frequency .........................................................................49
Saving a Memory File.........................................................................50
Opening a Memory File......................................................................50
Memory Stepping...............................................................................50
Scanning.................................................................................................51
Immediate Scanning (Searching) .......................................................51
Scanner Configuration........................................................................52
Groups ...............................................................................................53
Exclusions..........................................................................................53
Frequency Range Scanning...............................................................54
Memory Scanning ..............................................................................56
S-meter ...................................................................................................57
Power Switch..........................................................................................59
Date and Time Displays.........................................................................59
Spectrum Analyzer ................................................................................60
Appendix A – Troubleshooting.............................................................66
Appendix B – Sound Card Controls.....................................................71
Appendix C – Dealing with Interference ..............................................73
Appendix D – Inside WR-G3XX Hardware............................................75
Appendix E – Inside WR-G3XX Demodulator......................................77
Appendix F – Developer Support.........................................................80
Appendix G – Hardware Options..........................................................81
Appendix H – Frequency Calibration...................................................82
Appendix I – S-meter Calibration..........................................................84
Appendix J – USB Interface Diagnostics.............................................85
Declaration of Conformity...........................Error! Bookmark not defined.
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WiNRADiO G3XX VHF/UHF Receiver
Introduction
Welcome to the WiNRADiO G3XX receiver. This advanced receiver is the
result of a quest to combine many years of accumulated know-how in
computer-based radio receivers with the latest advances in components and
digital signal processing techniques.
In designing this receiver, we strived to provide the optimum balance of
sensitivity, selectivity and dynamic range, yet maintaining low cost and
implementing a number of significant features previously available only on
receivers significantly more expensive, bulky and far less friendly to the user.
While we attempted to implement many more features and functions than
normally would be found on a typical communications receiver, we also strived
to keep the control panel streamlined, logical and easy to use.
The WiNRADiO G3XX receivers transform any modern PC desktop into a
sophisticated VHF/UHF monitoring station offering surprising power and
flexibility, and enjoyment of use.
We hope you will like the spectrum analyzer with a 16 Hz resolution
bandwidth, continuous IF bandwidth adjustment in 1 Hz steps, graphical passband tuning, graphical notch filter, ultra-sensitive, selective and accurate Smeter, the convenient tuning and scanning facilities, the test and measurement
functions, and many other innovative features.
The WiNRADiO G3XX is not designed to be an ordinary radio receiver. It is
intended to be an exemplary radio communications instrument, crafted with
meticulous care and dedication to excellence.
We wish you much success and many hours of enjoyment in putting it to your
good use.
Please don’t forget to register as a WiNRADiO user to receive news about new
products, accessories and software upgrades for your G3XX receiver. Use our on-line
registration form at www.winradio.com/register to take advantage of this free service.
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WiNRADiO G3XX User’s Manual
G3XX Receiver Models
There are two basic models of the WiNRADiO G3XX receiver:
• G3XXi (PCI card based “internal” model)
• G3XXe (USB based “external” model)
Both receivers have similar parameters and similar software user interface.
This manual covers the installation and operational aspects for both types.
The G3XXi model has two connectors: the antenna connector (SMA type,
50 ohm) and an audio output:
The audio output is compatible with a PC sound card Line input, or can be
simply connected directly to an amplified multimedia speaker, or any other
suitable audio equipment. Standard 3.5mm stereo audio jack is used.
The advantage of this model is that it does not require any external power
supply, and does not occupy any additional desk space. The receiver is very
well shielded to prevent any interference generated by the PC from entering
the receiver. The receiver comes with a suitable “audio lead” to connect the
audio output to a sound card input.
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WiNRADiO G3XX VHF/UHF Receiver
The external G3XXe model has three connectors:
The power jack accepts 12 V DC (the power adapter must be rated for
minimum 500 mA). To minimize interference, a linear-mode power adapter is
recommended (as supplied by WiNRADiO).
The antenna input is an SMA-type connector with 50 ohm impedance.
The USB interface is compatible with both USB 1.0 and 2.0 standards and
serves to connect the receiver to a desktop or a laptop computer.
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WiNRADiO G3XX User’s Manual
Installation
The WiNRADiO G3XX package contains the following items:
• WiNRADiO G3XXi or G3XXe receiver
• USB interface cable (G3XXe receiver only)
• WiNRADiO software on a CD ROM
• Start-up indoor antenna
• Audio cable (G3XXi receiver only)
• This User’s Guide
• Warranty information
In order for the WiNRADiO receiver to function, your IBM PC compatible
computer must meet the minimum system requirements specified below.
System Requirements
Minimum Recommended
CPU 500 MHz,
Pentium III
RAM 64 MB 256 MB or more
Display SVGA SVGA (16 mil. colors)
HD free space 20 MB 40 MB
Sound card* SoundBlaster
compatible 16 bit
OS Windows
98/ME/2000/XP
* Sound card is only required with the G3XXe model (for playback only)
1GHz or higher,
Pentium IV or Athlon
Creative Sound Blaster,
16 or 32 bit
Windows 2000/XP
Do you have any suggestions about how we could further improve our product, or do
you wish to tell us of your experiences using this receiver in your application? Please
do not hesitate to leave your comments on www.winradio.com/feedback. We always
love hearing from you.
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WiNRADiO G3XX VHF/UHF Receiver
Hardware Installation
G3XXi model (PCI card)
1. Turn the computer off and disconnect the power cord.
2. Remove the computer case. Choose an empty PCI slot, as far as possible
from the power supply and from other cards.
3. First touch the computer metalwork with your hand to drain any static
charge, then carefully insert the card into the vacant slot and push down
until it is firmly seated. Screw the metal bracket at the end of the card to
the computer case. (This must be done to provide proper grounding for the
card).
4. Replace the computer case and reconnect the power cord.
5. Connect the supplied audio lead between the receiver output (a standard
audio jack) and the sound card Line Input. (If there is no Line input on your
PC, as is the case with some laptops, you may use alternative inputs, such
as the Microphone input.) Or, if you prefer, you can connect the receiver
directly to an amplified speaker or other suitable audio equipment.
G3XXe model (external model)
1. Connect the receiver to the USB port.
2. Connect the supplied power adapter to the power outlet on one side and
the power lead to the receiver on the other side.
3. Turn the receiver on using the power switch at front of the receiver. The
blue LED will first flash slowly, indicating that the receiver is ready. (The
flashing pattern of the blue LED has diagnostic meaning. For more
details, see Appendix J, USB Interface Diagnostics.)
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WiNRADiO G3XX User’s Manual
With the G3XXe model, the demodulated audio is travelling over the USB
interface, so no connection to a sound card is necessary, except, of course,
the speaker output.
Finally, connect the supplied start-up antenna to the SMA connector at the
rear of the receiver. Extend the antenna so that it is as far away from the
computer as possible.
Software Installation
1. If the PC is off, turn it on. Windows will find the recei v er and automatically
start the usual New hardware found driver installation routine. Insert the
installation CD ROM into the drive, and follow on-screen instructions.
2. After installing the drivers, choose the Run command from the Start menu
in Windows and type D:INSTALL (if the CD ROM is the D: drive on your
PC).
3. This will run the application installer, which will guide you in the installation
process.
4. After all the files have been installed to your hard disk, run the WiNRADiO
G3XX application.
Note: If the receiver is not detected by Windows, you can simply skip the driver
installation procedure, insert the CD ROM, and run the installation program,
which will also install the drivers.
WiNRADiO also manufactures a wide range of
antennas and antenna accessories suitable for many
applications. The WiNRADiO AX-71C antenna
(pictured) is especially suitable for the G3XX
receivers. Visit our web site www.winradio.com for
more information about WiNRADiO range of antennas
and antenna accessories.
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WiNRADiO G3XX VHF/UHF Receiver
Setting up the Sound Card
The G3XXe receiver’s audio travels via the USB interface in a digitized form,
to be played back by the sound card. The volume can be adjusted using the
Wave volume slider (which must be unmuted) or the master Volume Control.
The G3XXi receiver’s audio output is an analog Line Output. You can connect
this directly to standard amplified speakers, an external amplifier of your
choice, or your PC sound card. If you are using the sound card, the receiver
output should be physically connected to the Line Input of the sound card.
Double click on the speaker icon in the task bar, to bring up the sound card
Volume Control panel:
Make sure the Line Input is not muted, and the volume is set to approximately
half, to get started. (If the maximum volume as set on the receiver panel is not
sufficient, you may wish to increase the sound card volume later.)
If you are using the Microphone input instead of Line input, please check if
there is an Advanced button under the Microphone volume control in the
sound card control panel. If so, then click on it and uncheck the +20dB gain
check box if it exists. (The extra large gain might result in overloading the
sound card and cause distortion.)
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WiNRADiO G3XX User’s Manual
Connecting the Antenna
Unless you already have a proper antenna in place, you might like to take
advantage of the supplied start-up antenna which comes with your G3XX
receiver.
This antenna consists of a 3-metre length of a coaxial lead-in cable, with an
additional 3 metres of insulated wire. The thinner, insulated wire at the end of
the coaxial cable is the actual antenna. It is necessary for the lead-in cable to
be as far away from the PC as possible, to reduce potential interference from
the PC.
Please note that this start-up antenna is supplied for initial tests and immediate
gratification only. It is not intended to replace a proper antenna.
The best placement of the start-up antenna depends on your actual situation,
and will often involve some experimentation. However, the basic rule is
simple: Place the antenna as close to the window as you can, and keep the
active part of the antenna as far away from the PC, and other electronic and
electrical devices, and metal objects, as possible.
An example of start-up antenna placement
No matter how good a radio receiver is, the performance of the entire receiving
system will depend on the quality of the antenna. The same applies to a
WiNRADiO receiver. To make the most of your G3XX receiver, you should
install a proper antenna. WiNRADiO may also be able to assist with our wide
range of suitable antennas – check our Web page www.winradio.com.
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WiNRADiO G3XX VHF/UHF Receiver
Getting Started
There is often a degree of understandable impatience when exciting new
equipment such as a new WiNRADiO receiver is acquired. The following fastforward introduction makes it possible for you to start using your new
acquisition as quickly as possible. Detailed operation is described in the
subsequent chapters. We hope you will return to these chapters, as the
WiNRADiO G3XX receiver has many fine features which would be a shame to
miss.
Start the WiNRADiO G3XX receiver application (by double clicking on the
WiNRADiO icon). The WiNRADiO G3XX receiver control panel will appear as
shown in the following picture:
WiNRADiO G3XX Receiver Control Panel
The WiNRADiO G3XX receiver control panel has some elements simila r to
conventional receivers, and many additional features as well.
The quickest way to get started with this receiver is to check its operation on
your local AM stations.
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WiNRADiO G3XX User’s Manual
Using the keyboard, type in the frequency of one your local AM stations: For
example, for 774 kHz, type in 7 7 4 , then k for kHz, then press Enter. The
typed-in frequency will appear on the digital frequency display. Then select
the AM mode by clicking on the AM button. At this point, you should be able to
see the station peak on the real-time spectrum scope, and hear the station.
Adjust the bandwidth for optimum reception using the row of numbered
buttons at the bottom of the spectrum scope panel: these represent preset IF
bandwidth. To adjust the IF bandwidth smoothly, use the IF bandwidth control
at bottom left.
You can adjust the volume using the two buttons next to the small Volume
display. (Note also the little slider between these two buttons: you can drag it
up and down to change the volume faster.) An alternative way to adjust the
volume is by using the left/right arrow keys of the PC keyboard.
Manual tuning can be done in several ways. Let’s start with the tuning knob:
Place the mouse cursor onto the upper half of the tuning knob, at which point
you will see the cursor change to a curved double ended arrow. Hold down
the right or left mouse buttons to increase or decrease the frequency, and the
knob will rotate clockwise or anti-clockwise, respectively.
If you place your cursor onto the bottom half of the tuning knob, the direction of
the rotation will reverse. (You don’t need to move the cursor up or down to
change the rotation of the knob, simply press either the left or right mouse
button.)
The rotation increment of the tuning knob is 0.5 kHz. This can be changed
easily using the Shift, Ctrl or Alt keys: If you press the Shift key while tuning,
the increment will increase ten times (to 5 kHz). Pressing Ctrl will increase the
increment a hundred times (50 kHz). On the other hand, if you use the Alt key,
the increment becomes ten times smaller: 50 Hz.
Another way of tuning is to use the up and down arrow keys on the PC
keyboard. If your mouse has a wheel, you can also use this: you might find it
somewhat similar to using the tuning knob of a conventional receiver.
If you are unable to tune to any stations at this point, please refer to Appendix
A - Troubleshooting. There are many other ways to tune the WiNRADiO
receiver other than typing the frequency or using the tuning knob. These will
be explained in detail in the following chapters.
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WiNRADiO G3XX VHF/UHF Receiver
Tuning WiNRADiO G3XX
Manual Frequency Entry
To change frequency, simply type the new frequency into the keyboard. As
soon as you press a number or decimal point, the frequency display will
activate, waiting for a frequency to be typed. You can also click on the display
to type in a new frequency in a highlighted field. After typing the new
frequency, press Enter and the receiver will instantly retune. To abort, press
Escape. To enter units, such as kHz or MHz, simply press k for kHz or m
for MHz after entering the digits. Any invalid keystrokes are ignored.
Frequencies outside the receiver limit (9 kHz to 30 MHz) will not be accepted
and the display will revert to the previous frequency.
Use the kHz or MHz buttons to select how you wish the frequency to be
displayed.
The up/down buttons under the individual digits make it possible to quickly
step up or down the frequency in the corresponding positions. (The little slider
buttons between the up/down buttons can be used for faster adjustment.)
The VFO buttons make it possible to select from four different VFOs. A VFO is
a kind of frequency memory making it possible to quickly switch between
several frequencies. For example, if you tune to Frequency 1 using VFO1, and
Frequency 2 using VFO2, then you can alter between Frequency 1 and
Frequency 2 by simply clicking on the corresponding VFOs.
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WiNRADiO G3XX User’s Manual
Under these buttons there is a Band description window. This window
shows the band allocation of the currently tuned frequency. While the
displayed band descriptions are specific to the North American standard, they
are based on international treaties and therefore are generally applicable
worldwide with minor differences, which can be easily edited by the user.
The band descriptions can be overridden with a call sign or a user-defined
description of a particular frequency stored in memory. This overrides the band
description for a particular frequency only.
It is also possible to change the naming and frequency allocations for entire
frequency bands. This can be done by editing the file called bands.csv in the
WiNRADiO installation folder. (This is a standard “comma-separated-value”
format file which can be edited using a spreadsheet application, such as
Microsoft Excel.)
Did you know?
VFO stands for Variable Frequency Oscillator. This is a historical term dating
back to the era of analog tuned radios. Before digitally tuned receivers were
invented, there was no easy way to store and recall frequencies. Professional
receivers had switchable oscillators where the oscillators (and their variable
capacitors) themselves served as analog frequency memories. The name and
the net effect remain, but the principle has changed: There is no need for
multiple oscillators in modern receivers to implement this function. The
frequency is simply stored in a digital memory.
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WiNRADiO G3XX VHF/UHF Receiver
Tuning Knob
The Tuning Knob makes it possible to adjust the frequency in fixed 50 Hz,
500 Hz, 5 kHz or 50 kHz steps.
To use the tuning knob, position the mouse cursor over the knob (the cursor
will turn into a curved double ended arrow) and click on either the left or right
mouse button. If the cursor is on the top half of the knob, the left button will
decrease the frequency, and the right button will increase the frequency. If the
cursor is in the lower half, the opposite will occur (and the cursor will invert its
shape).
You don’t need to move up or down with the cursor to change the rotation of
the knob. Simply press either the right or left mouse button.
As the knob rotates, the frequency will change in 500 Hz steps. Holding the
mouse button down will accelerate the tuning.
The step size can be changed to 50 Hz, 5 kHz or 50 kHz, using the Alt, Shift
or Ctrl keys, respectively, while clicking the tuning knob with mouse button.
Note that the Fine Tune Knob can also be conveniently rotated using a wheel
of a wheel-equipped mouse, or any other standard Windows-supported
pointing device.
Keyboard Tuning
The receiver frequency can also be adjusted using the keyboard cursor control
keys (the “arrow” keys): Using the up/down arrow keys, the frequency
changes in 10 Hz steps. Pressing the Shift key simultaneously results in 100
Hz steps, while the Ctrl key changes the step size to 1 kHz.
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WiNRADiO G3XX User’s Manual
Incremental Tuning Pad
This unique tuning tool is located above the Tuning Knob. If the mouse is
positioned above one of the coloured squares, the square lights up and the
associated tuning increment value appears:
Clicking on the square with the left mouse button results in increasing the
frequency, clicking with the right mouse button will decrease the frequency.
There are several convenient tuning increments to choose from: 1 Hz, 10 Hz,
100 Hz, 1 kHz, 5 kHz, 6.25 kHz, 8.33 kHz, 9 kHz, 10 kHz, 12.5 kHz and 25
kHz.
Tune To Peak
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.
In the FM mode, the Tune to Peak function will work correctly, i.e. tune to the
centre of the signal, even though the sidebands may be higher than the carrier
frequency.
In LSB and USB modes, the success of this facility will depend on the type of
modulation signal. It may be useful for certain types of data modulation (fax),
but is not usually recommended for voice modulation.
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WiNRADiO G3XX VHF/UHF Receiver
AFC (Automatic Frequency Control)
The Automatic Frequency Control function is activated by pressing the AFC
button. It will keep the receiver tuned to the selected station if the transmitter
frequency drifts.
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.
Frequency Stepping
The Frequency Stepping facility makes it possible to specify an arbitrary
frequency step size. To change the step size, click on the associated display
and enter the required value (from 1 Hz to 1 MHz). You can also use the up
and down buttons on the right of the display, to select from commonly used
step sizes. For convenience, you can also use the small slider between the
two buttons.
When the step size is selected, you can step up or down from the
currently displayed frequency using the left or right arrow buttons
under the step size display. The double-arrow buttons further
down will cause stepping by a step size ten times larger.
Stepping can also be done using the keyboard Pg Up or Pg
Down keys.
For example, if you wish to browse the AM broadcast band
(approx. 530 to 1620 kHz), set the step size to 10 kHz (for North and South
America) or 9 kHz (for the rest of the world), which is the channel separation
for AM broadcast stations.
Tune manually to any station first, then step up or down to browse the band.
To browse the shortwave broadcast stations (2.3 to 30 MHz), 5 kHz works
well.
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WiNRADiO G3XX User’s Manual
This type of fixed-size stepping is convenient if you wish to explore a
frequency band where the channels are equally separated. However, you
should ensure that the stepping frequencies fall on the actual channel
frequencies in the band. If you know the channel separation but are unsure
about the exact frequency of the first channel, tune to an active channel using
manual tuning first, and only then step up or down in fixed steps.
The Auto button engages Auto-stepping, which provides a significant
enhancement over fixed stepping. When properly configured, auto-stepping
will automatically set the step size according to the frequency you are tuned to.
Auto-stepping can be also used to associate particular mode and squelch
settings with specified frequency ranges.
To configure the auto-stepping ranges, go to Options | Autostepping in the
top bar menu. The following window opens:
You can use the New button to add a new range. For each range, you need to
specify the start and end of the range, step size, and optionally mode, squelch
and description. You can specify as many such bands as you like.
When done, close the window.
Next time when you tune to a frequency, and the Auto button is pressed, the
step size (and optionally mode and squelch) will be set to the predefined value
if the new frequency falls within a specified auto-step range.
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WiNRADiO G3XX VHF/UHF Receiver
The Demodulator
The heart of the G3XX receiver is its demodulator. The demodulator is entirely
software-defined, implemented using optimized filtering and quadrature
demodulation techniques and executed inside the receiver’s on-board DSP. All
the functions related to the demodulator, i.e. demodulation mode settings,
volume control, IF filter bandwidth, IF shift, RIT, software AGC, AF squelch,
notch filter, noise blanker, recorder/playback and real-time spectrum display,
are grouped together in an area of the front panel of the receiver which is
referred to as the Demodulator Panel. This panel is in fact a separate plug-in
to the main receiver panel, and can be replaced by other demodulators, either
developed by WiNRADiO or third parties.
Selecting Demodulation Mode
To select the demodulation mode, click the appropriate mode button in the
demodulator panel:
22
WiNRADiO G3XX Demodulator Panel
WiNRADiO G3XX User’s Manual
In addition to the usual and self-explanatory AM, LSB, USB, CW and FM
modes, there is also AMS (synchronous AM), DSB (dual sideband,
suppressed carrier) and ISB (independent sideband).
For ISB, the audio output can be selected between the lower and upper side
bands using two selector USB and LSB buttons accessible under the Setup
button:
Note: Both channels of the ISB transmission can be recorded simultaneously
using the recording facility of the G3XX receiver. (In such case, the LSB and
USB signals are recorded as left and right channels of a stereo recording.)
Real-time Spectrum Scope
The real-time spectrum display shows the actual situation within the bandwidth
of the receiver. The actual filter bandwidth is 15 kHz, but the spectrum scope
shows a somewhat wider area of 20 kHz, hence the sloping edge s. Whe n you
press the mode buttons, you will note that the central highlighted region of the
spectrum changes its width. This corresponds to the IF (intermediate
frequency) filter bandwidth associated by default with the different modulation
modes. All these default values can be overridden and finely adjusted.
The Video filter is a low-pass filter used to smooth the displayed
spectrum.
When activated, the smoothness of the spectrum trace increases
when the cut-off frequency decreases. The frequency can be adjusted either
by direct typing in the edit box, or by clicking the up/down arrow keys, or, more
conveniently, by dragging the little slider between the up/down keys.
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WiNRADiO G3XX VHF/UHF Receiver
Spectrum trace without video filter
The same signal with video filter set at 3300 Hz
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WiNRADiO G3XX User’s Manual
The zoom in and out buttons change the displayed signal bandwidth
in 2 kHz steps, while trying to keep the central red marker as close as possible
to the center of the spectrum display. Using the zoom buttons, the displayed
bandwidth can be changed from the default 20 kHz down to 4 kHz, making it
possible to observe small details of the received spectra less than 20 Hz apart.
Setting and Adjusting IF Bandwidth
The receiver IF bandwidth can be set in several ways. The quickest way is to
use the IF bandwidth presets represented by the row of buttons at the bottom
of the demodulator window:
The numbers on the buttons represent bandwidth in kHz.
The preset frequencies change according to the mode
selections.
All these frequencies can be changed by the user, for
each mode, using a table of IF bandwidth presets
accessible via the demodulator Setup button.
There are 15 presets, associated with the 15 preset
buttons.
Clicking on the actual number in the Bandwidth column
makes it possible to edit the IF bandwidth value
associated with each button. The button label will then
also change accordingly. Each modulation mode has its
own set of IF bandwidth presets.
To change the IF bandwidth continuously, you can use
the IF bandwidth control in the demodulator panel:
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WiNRADiO G3XX VHF/UHF Receiver
There are three ways you can use this control:
• Type the IF bandwidth directly into the edit box, in Hz (type in a number
from 1 to 15000, followed by pressing Enter).
• Use the small up/down cursor keys to adjust the
frequency by 1 Hz steps.
• Use the small slider located between the up/down
cursor keys and move it up or down. This is quite a
fast and convenient method.
Another very convenient method is to adjust the IF bandwidth graphically on
the real-time spectrum display, by dragging the red line bordering the shaded
area representing the IF filter bandwidth:
This method makes it possible to adjust the bandwidth accurately to fit the
actual bandwidth of the received signal, obtain the best signal-to-noise ratio
and minimize interference from adjacent channels.
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