WiNRADiO ® G303 Shortwave Receiver User’s Guide i
Published by WiNRADiO Communications PO Box 6118, St Kilda Road, Melbourne 3004, Australia © 2004 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, G303 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.
FCC Notice The WiNRADiO G303 receiver 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.
Introduction Introduction One could easily conclude that, in the era of the Internet and communication satellites, short waves are destined for obsolescence. But the reality is quite different. On the contrary, shortwave communications seem to be experiencing a new period of revival and vigorous growth.
Installation G303 Receiver Models There are two basic models of the WiNRADiO G303 receiver: • • G303i (PCI card based “internal” model) G303e (USB based “external” model) Both receivers have similar parameters and identical software user interface. This manual covers the installation and operational aspects for both types.
The external G303e 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 IF output/control connector combines the 12 kHz IF (intermediate frequency output), USB interface and serial interface.
It is also possible to control the receiver via the serial (RS-232) interface, which necessitates using the PC sound card for digitization of the IF signal. WiNRADiO provides a special “serial interface option” cable which takes care of all the appropriate connections, both to the serial port and the sound card input.
Installation The WiNRADiO package contains the following items: • • • • • • • • WiNRADiO G303i or G303e receiver WiNRADiO software on a CD ROM Start-up indoor antenna Audio cable (G303i model only) Power adapter (G303e only) Interface cable (G303e 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.
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.
G303e (external) model with standard USB interface 1. Connect the receiver to the USB port using the supplied cable. 2. Plug the supplied power adapter to the power outlet and connect its output to the receiver. 3. Turn the receiver on using the power switch at front of the receiver. The blue LED will blink to indicate that the receiver is ready.
G303e (external) model with optional serial interface 1. Connect the receiver to the serial port using the supplied adapter, which combines both the serial interface and the audio lead in one cable. 2. Connect the audio lead on the PC side to 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. This may be also necessary with certain types of sound cards, such as Creative Audigy 2.) 3.
G303e LED status indication The single blue LED on the front of the WiNRADiO G303e (external) receiver can display a number of different states using various specific flash patterns. Each pattern is repeated once per second. In the following table, “black” in the pattern indicates that the LED is on in that time interval.
Connecting the Antenna Your WiNRADiO G303 receiver comes with a start-up antenna consisting of a 3-meter length of coaxial lead-in cable, with an additional 3 meters of insulated wire. The thinner, insulated wire at the end is the actual antenna. The long lead-in cable is necessary for the antenna to be located as far away from the PC as possible, to reduce interference from the PC.
An example of WiNRADiO 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 WiNRADiO receiver, you should install a proper shortwave antenna. Check out our antennas There are many vendors offering shortwave antennas. WiNRADiO with our extensive range of antennas may also be able to assist.
Software Installation 1. If the PC is off, turn it on. Windows will find the receiver and automatically start the usual New hardware found driver installation routine. Insert the installation CD ROM into the drive, and follow onscreen instructions. (Note: Windows NT will not automatically detect the receiver, as it does not support Plug and Play.) 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.
The demodulator set-up window opens, as shown: The Wave device drop-down list shows all the installed wave devices: Windows default is the Control Panel setting specified under Start | Settings | Control Panel | Multimedia Properties | Audio. If a sound card is specified in this Control Panel setting for both playback and recording (this is very likely, but not always necessarily so), then you can simply select Windows Default as the wave device for the demodulator.
The next parameter to select is the mixer device associated with the already selected sound card, using the Mixer device drop-down list, and the Mixer line (the sound card input line). If the signal is arriving at the sound card via an external cable, the cable should be physically connected to the Line input of the sound card. If the receiver is connected internally, most probably the input would be called Aux or CD Line.
Firstly, in the sound card Playback volume control panel, the software mutes the sound card input line the receiver is actually connected to. This is the same line as selected in the WiNRADiO G303 demodulator Setup, i.e. usually, this will be Line or Microphone input. This may seem a bit unexpected: Why are we muting the input line? This is because the signal coming from the receiver is not an audio signal, but rather the intermediate frequency signal.
The Volume slider of the Recording Control is duplicated in the demodulator Setup panel (where it is labeled Input level). Please pay great attention to the sound card set-up, as most initial problems associated with using this type of receiver can be attributed to an incorrect sound card setting.
Getting Started There is often a degree of understandable impatience when exciting new equipment such as a new WiNRADiO receiver is acquired. The following fast-forward introduction makes it possible for you to start using your new acquisition as quickly as possible. Detailed operation is described in the subsequent chapter Using WiNRADiO G303 Receiver. We hope you will return to that chapter, as the WiNRADiO G303 receiver has many fine features which it would be a shame to miss.
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 hear the station. 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.
Using WiNRADiO G303 Tuning to a Frequency To change frequency, simply type the new frequency into the keyboard. As soon as you press a digit 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. After typing the new frequency, press Enter and the receiver will instantly retune. To abort, press Esc. To enter units, such as kHz or MHz, simply press H for Hz, K for kHz or M for MHz after entering the digits.
Fine Tuning The Fine Tune knob makes it possible to finely adjust the frequency in 0.5 kHz steps. WiNRADiO G303 Receiver Tuning Knob 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.
Fast Tuning Pad This unique fast-tuning facility is located under the Attenuator, IF Gain and Squelch settings. Fast Tuning Pad If you place the cursor inside the long horizontal window of the Fast Tuning Pad, you will see a frequency increment displayed, which can vary from 1 Hz to 1 MHz in convenient steps. The value of this increment can be changed quickly by moving the cursor horizontally within the Fast Tuning Pad. The current increment value is always shown under the pad.
WiNRADiO G303 Standard Demodulator Panel The real-time spectrum display shows the output of the receiver (i.e. the intermediate frequency signal) as it is applied to the PC sound card. When 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 with the different modulation modes.
WiNRADiO G303 Professional Demodulator For details of the many additional functions such as continuous IF bandwidth adjustment and other special features of the Professional Demodulator, please refer to Appendix E - Professional Demodulator. Volume Control The Volume control is also located in the demodulator panel. The volume can range from 0 (no sound) to 31 (full volume). To enter a value directly, click on the display and type in the new volume level.
Mute Control Next to the Volume control is the Mute button, which allows you to switch off the audio output quickly. It is faster to use than setting the volume to zero, with the added benefit of not changing the set volume level. To use the mute control, simply click on this button. Click again to release. AGC The AGC (Automatic Gain Control) has four settings: Off, Slow, Medium and Fast. These make it possible to disable the AGC, or to select the speed with which the AGC reacts.
IF Gain The AGC can be turned off using the AGC Off button. The receiver gain must then be adjusted manually. This is done using the IF Gain control. Note that by setting an excessive gain, the receiver will overload and the demodulated signal will be distorted. On the other hand, if the gain is too low, it will make the receiver appear “deaf”. Manual IF Gain setting is useful when hunting for very weak signals buried in noise.
Attenuator The Attenuator makes it possible to reduce the receiver sensitivity by 18 dB (i.e. 6 times). Attenuator Why would you ever need to reduce the sensitivity? This is because unusually strong signals from local stations may occasionally cause overloading. This overloading can make the reception worse, and even cause stations to appear on frequencies, where none exist (ghost stations). See Appendix C - Dealing with Interference for more information on this phenomenon.
The squelch is always shown in dBm units. To adjust the 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).
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.
Frequency Memory The WiNRADiO G303 receiver has the ability to store up to one thousand frequencies in one memory file. It also allows you to load and save different memory files for a huge amount of total storage, limited only by the size of your hard disk. Memory Control Panel Storing a Frequency into Memory With each frequency, you can store several attributes: mode, callsign, user comment, group assignment, squelch and a hotkey.
Storing Frequency to Memory At the top of the dialog box is the frequency you are storing. The next line shows the next available memory number. You can change this to another memory number if you wish (including one which is already allocated). The third item contains the group assignment buttons. You can assign the frequency to one or more of 16 different groups (whose meaning you define yourself).
• For quick tuning to your favorite stations, you can assign Hotkeys (function keys F2 to F12) for up to eleven different frequencies. If you then press a hotkey, the associated frequency will be instantly recalled. Hotkeys which are already assigned will be shown in this dialog box as ‘used’, however you can overwrite the previous assignment with a new one if you wish. • User Comments can also be stored with a frequency. The size of the comments is limited to 31 characters.
Recall Frequency from Memory The assigned memory groups are shown as color bars for a quick visual overview of which frequencies are associated with which groups (see the corresponding colors in the Store frequency window). When you position the mouse cursor over a highlighted memory, the actual group numbers will be displayed in a floating ‘hint’ box. Editing Memory To change the settings for a particular frequency, open the Recall frequency dialog box as described in the previous section.
Saving a Memory File Each memory file, containing up to one thousand frequencies, is stored separately, allowing different memory files to be loaded and saved. To save the current memory file, simply select Save from the Memory file sub-menu in the File menu. If you wish to save it with a different name, select Save as instead, and a dialog box will pop up allowing you to specify the file name.
The scanning method is selected using the appropriate button in the Scanning Control Panel: Scanning Control Panel Immediate Scanning (Searching) This is the simplest scanning method. Click on the Search button to select this scanning mode, then use the [>>] or [<<] buttons to scan either forward or backward from the currently tuned frequency. To stop scanning, press the Stop button (marked with a green square). To pause, press the Pause button (marked with two vertical bars).
Scan Settings There are two basic actions the software can do when a signal is found: Pause scanning or Stop scanning. If Pause is selected, then you need to further specify the conditions under which the scanning will Resume. The conditions to resume can be one of the following: 1. When the signal disappears (i.e. the scanning resumes immediately when the signal disappears); 2. After a certain user-defined Delay time (i.e.
Note that the upper scanning speed limit may be restricted by the available CPU resources of your computer. When a signal is found and scanning pauses, waiting for the pre-set Delay time to expire, the countdown timer will appear inside the [<<] or [>>] buttons. If no Delay time was set and scanning is pausing until the signal disappears, then the [<<] or [>>] button will flash.
Setting up Scan Ranges Enter a new range using the New button. This will open a dialog box, where you will be asked to specify lower and upper limit frequencies of the range, the modulation mode, squelch level, and, optionally, a description.
When the range definition is done, close this window, then close the scanner settings. Then activate the Range button in the Scanning control panel: Scanning Control Panel When you press the Scan Forward button [>>], the scanner will commence scanning from the start frequency of the first range. When the last frequency of the first range is reached, it will then continue onto the next range, etc.
Note that if more signals are found than there are allocated memories, the excess frequencies will not be stored. Memory Scanning The last scanning method is Memory Scanning. Here the receiver will step through memory frequencies, starting from the first one to the last one, and repeating the loop until a signal is found or until manually stopped. If a squelch value is stored with a memory, its value will be used to compare with the current signal level.
the squelch level (i.e. the needle falls in the red region and turns red also), the receiver audio will be muted and “squelched” will be displayed. The squelch value is always indicated in dBm units (even if the signal strength is displayed in S-units or microvolts). Note that when the AGC is off (and manual IF gain control is activated), the S-meter is disabled. This is because the S-meter relies on the AGC for its proper function.
Spectrum Scope In addition to the narrow-band real-time spectrum scope, which is located inside the demodulator panel, the G303 receiver also has a wide-band spectrum scope which operates by fast tuning the receiver across the userspecified frequency range.
There are also two Zoom in/out buttons performing their self-explanatory functions, and a Clear button, which clears the graph and the min/max values. Clicking anywhere on the spectrum graph tunes the receiver to the corresponding frequency. You can also drag the mouse horizontally across the spectrum and continuously tune the receiver. To hide the Spectrum Scope, use the yellow triangle button next to the power switch again.
Appendix A - Troubleshooting Problem (G303i or G303e with serial interface option only): My PC does have a Line input, but there is no such Line input shown in the mixer line list in the demodulator set-up window. Solution: The mixer line list is provided by Windows. It shows all available mixer channels which are capable of full duplex operation. It appears that the Line input of your sound card is not capable of full duplex operation.
Problem: I can hear the audio and tune the receiver, but the volume is too low, even if I adjust the Volume control to maximum. Solution: Engage the Audio AGC in the demodulator front panel (typically, the Med setting is used). G303i or G303e with serial interface option only: Also check the Input gain in the demodulator Setup panel: it should be set as high as possible, just below the clipping level.
Note: If you have difficulties accessing the sound card control panels (for example if there is no speaker icon), refer to Appendix B – Sound Card Controls. • The receiver demodulator has not been set up properly. Make sure that the sound card type and the audio input are properly selected (this panel is accessible under the Setup button in the demodulator panel): • The sound card has the left and right inputs reversed.
Problem: I can tune the receiver and see the signal peaks in the spectrum scope, but I can’t hear any sound at all. Solution: Check that your speaker or headphone is connected to the speaker output of the sound card. Set the volume to medium (say 15), the squelch to the lowest value (-130 dBm) or defeat the squelch by clicking on the Def button. Make sure the Mute button in the demodulator panel is released, too, and the speaker output of the sound card is unmuted in the sound card control panel.
Problem: I can hear the audio and tune the receiver, but the audio drops-out occasionally, and the display is very sluggish, sometimes it even freezes. Solution: Close all other simultaneously running programs to reduce the burden on the CPU. If the CPU usage shows consistently more than 80%, this may indicate insufficient CPU resources for the G303 application. (Check the CPU usage under the Setup button in the demodulator window. The CPU resource meter is at bottom left.
Appendix B – Sound Card Controls Sound card control panels and their settings can be somewhat confusing. They are also rather inconsistent from one version of Windows to another. WiNRADiO G303 receivers require a full duplex sound card, meaning that the card must be able to simultaneously process signals in two directions (i.e. record and playback) at the same time. The majority of modern Sound Blaster compatible cards are indeed like that. However, some older cards may not be full duplex.
Windows NT 98 Enable “speaker” icon Recording/playback volume controls Control Panel | Multimedia Audio-tab Checkbox: “Show volume control on the taskbar” Make sure the speaker icon is displayed, then double-click on the speaker icon in task bar to display the Volume Control dialog.
Appendix C - Dealing with Interference Electromagnetic Interference (EMI) is what prevents us from receiving a clear signal, even when the receiver should be sensitive enough to receive it. There are many types of interference you can experience with radio receivers, emanating from both natural and man-made sources. Natural interference is produced by atmospheric phenomena such as storms and sun activity. Not so surprisingly, man-made interference is often worse.
monitors), or you can try to relocate your antenna further away from your computer. A good remedy to try is to wind five to ten turns of the antenna lead-in cable through a large ferrite core (the doughnut shaped toroid type), near the PC end of the cable. This suppresses common-mode interference, which is a typical but curable problem with PC-controlled receivers. Another type of interference which you may encounter is intermodulation interference.
Appendix D - Inside WR-G303 Technically minded users may like to explore the WiNRADiO G303 Receiver and experiment with some of the innovative concepts of Software Defined Radio. The WiNRADiO G303 Receiver is the world’s first commercially available Software Defined Radio, where the Demodulator function is fully performed in software running on a standard PC.
The second mixer again uses a DDS with a PLL to mix the 45 MHz signal down to the last intermediate frequency, which is 12 kHz. Both DDS circuits derive their reference frequency from a 20 MHz reference oscillator. The 12 kHz IF output is then fed to the right channel of the Line input of the PC sound card. You can hear what it sounds like if you use the sound card mixer panel to listen directly to this input (rather than using the G303 Demodulator software).
Appendix E – Professional Demodulator The WiNRADiO G303 receiver has provision for additional demodulators, in place of the supplied standard one. Installed demodulators can be selected via the Demodulators top bar menu. Check the WiNRADiO Web site www.winradio.com periodically, for available demodulators. The Professional Demodulator which is available as an optional extra, takes the concept of software-defined shortwave receiver a step further.
The front panel of the Professional Demodulator looks similar to the standard one. Note in particular the added DSB and ISB modes, the continuous IF filter bandwidth control, enhanced Audio AGC (the time constants are user definable in the Setup window), and a row of IF bandwidth preset buttons at the bottom. The numbers on top of the IF bandwidth preset buttons indicate the associated bandwidth (in kHz). These presets, too, are entirely user-definable.
upper limit). Starving the system of CPU resources manifests itself by the computer becoming sluggish or possibly "freezing" entirely. The first parameter, the IF bandwidth filter length, is the length of the first filter in the digital path, which is responsible for much of the receiver selectivity. The factory default length is 63. Reducing this value will decrease the receiver selectivity and make the receiver more prone to interference from nearby strong signals.
Hz. The buttons are numbered (1 to 10) from left to right. The factory default values can be restored at any time, by pressing the Restore default settings button. Each modulation mode has a separate set of IF bandwidth presets. For the AM, AMN, FM3, FM6 and FMN demodulators, a supplementary low-pass filter is introduced in the audio output path, to reduce harmonic distortion generated in the demodulation process and improve the overall signal-to-noise ratio under bad receiving conditions.
Demodulator Structure The G303 Professional Demodulator implements the general quadrature representation of all narrow-band modulated signals. Such signals can always be considered as the sum of two amplitude-modulated carriers having a 90 degree offset, usually referred to as I and Q.
The demodulator structure windows include two spectrum analyzers, making it possible to view signal spectra in real-time. Each analyzer can be "connected" to any of the test points shown as green dots in the diagram. To connect the left spectrum analyzer to a particular test point, left-click on the green test point. Its color will change to red. Right-clicking on a dot will connect it to the right analyzer, and the color will change to blue.
The LSB and USB demodulators have basically the same topology: USB Demodulator Structure ISB can be thought of as a combination of LSB and USB, where each of the sound card channels is used for one of the independent side bands. The CW received signals are first down-converted to zero Hz, and then, after additional channel filtering, up-converted to a convenient audio frequency.
Finally, all FM demodulators have the same block diagram. The only differences between these demodulators are the bandwidth values of the input IF filter and the two post-mixer filters: FM Demodulator Structure Did you know? All the software-implemented digital filters used in the G303 receiver are of the linear phase FIR (Finite Impulse Response) type, with maximum 255 taps, providing a filter shape far superior to conventional analog hardware filters.
Appendix F - Developer Support WiNRADiO has always extensively supported third-party software development efforts with all our receivers, and the WiNRADiO G303 receiver is no exception. We provide technical details for developers to be able to develop the following: 1. Third-party applications controlling the WiNRADiO G303 receiver. We do this by providing API information making it possible to access the receiver hardware from third party software. (See http://www.winradio.com/home/developer.htm). 2.
Appendix G – Frequency Calibration The G303 receiver series features an excellent frequency accuracy and stability for a receiver of its class. It is however possible to improve this accuracy yet further, by individual calibration. The receiver calibration is accomplished by inserting a reference frequency parameter in the wrg3.ini file which resides in the Windows directory.
Then subtract the frequency difference from 20000000. In our example, the resulting reference_frequency will be 20000000-(-1304)=20001304. The entire reference frequency parameter in the wrg3.ini file will be then as follows: [ClockCalibration] 02L27011=20001304 Save the wrg3.ini file, then restart the G303 application and observe the difference. To return to the original factory frequency calibration, simply delete the inserted two lines in the wrg3.ini file.
Declaration of Conformity This device, trade name WiNRADiO Communications Receiver, model number WR-G303 complies with Part 15 of the FCC Rules. Operation is subject to the following conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.
