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Australia has gone from a leading manufacturer of radios and components to almost exclusively importing electronics – usually displaying the ‘made in China’ label. With an upsurge of new technology like MP3, GPS, Bluetooth and much more, it’s a revelation to find an Australian company designs and manufacturers high-tech world-leading innovative radios, making an impact worldwide. by Kevin Poulter WiNRADiO ® An Australian Success Story 68  Silicon Chip siliconchip.com.au W iNRADiO receivers are no ordinary radios, as they link to computers for awesome performance. Why have few Australians heard of WiNRADiO? Because 95% of its products are sold overseas, to clients like the US and UK Defence Departments. Originally a small Melbourne-based start-up, WiNRADiO introduced its first product, an ISAbus based receiver WR-1000i back in 1995 at the Sydney PC show. The receiver won the show’s ‘Best New Hardware’ award. Featuring a frequency range of 150kHz to 1300MHz, the product was the world’s first commercially available wideband scanning receiver for the PC. Radio receivers and computers have kept a respectful distance apart until recently. The main reason for this was the electromagnetic ‘storm’ of noise emanating from computers, making PCs unfavorable to radio reception. There is also the dissimilar technologies and jargon. To a computer aficionado, a “megahertz” is the frequency the CPU runs at, not something you actually tune to. Engineers at WiNRADiO made the first successful attempt to marry radio and computer technologies with innovative concepts, resulting in international radio-related patents and trademarks. Significantly, they made the computer an essential component of a radio receiver, with their latest designs adapting the computer to cover almost half of the radio operation. This means much of the conventional receiver circuits normally accomplished with an array of components (such as intermediate frequency filters and demodulators) have been replaced with software running on an ordinary PC. With WiNRADiO receivers, all that’s needed is their “front end” USB box or a PCI-bus card, for almost any PC to be instantly transformed into a powerful VHF/UHF scanner or a shortwave receiver. It’s not just for Government services. Many enthusiasts or audiences like to listen in to shortwave and other bands. Shortwave is still the only mass-media capable of reaching the world without supporting infrastructure. Now, with the advent of digital DRM technology, shortwave is finding new markets and applications. siliconchip.com.au The WR-G313 Let’s look at their WR-G313 HF receiver, popular amongst serious radio users, such as major broadcasting corporations, defence establishments worldwide and amateur radio enthusiasts. The London-based “Word Radio TV Handbook” rates radio receivers annually and awarded the G313 a five star rating. The receiver comes in two forms: an internal PCI card (G313i), as shown at the top of this page or as an external USB box (G313e) – shown underneath. Their performance is identical – the only difference is the hardware interface. The external G313e unit is housed in a small (164 x 96 x 41 mm) case, while the internal model is based on a 3/4-length standard PCI bus card, ready to to plug in and use. The only hint that they are a radio receiver is an SMAtype connector marked “antenna”. On the USB model, remaining external features are simply the power and USB connectors, power switch and blue LED. Frequency range of the WR-G313 is 9kHz to 30MHz, optionally expandable to 180MHz. Plug-and-Play installation is simple and similar for both models: just connect the device, insert the supplied CD ROM, and let Windows guide you through the usual device driver installation process. On completion, a rather impressive control panel appears (shown next page). January 2007  69 The screen At first look, there’s quite a resemblance to conventional radio receivers, with the tuning dial “knob”, frequency display and signal strength meter. A closer look reveals even more bells and whistles – eg, Notch filter and Noise blanker, plus a number of unusual demodulation modes. These advanced features, such as the real-time spectrum display which shows the actual spectrum of the station you are tuned to, are not typically found on any conventional radio. Further, press one of the yellow triangle buttons beside the on/off switch and an additional “sweeping” spectrum analyser neatly slides out at the bottom: Computer technology enables even more interesting goodies, not seen on a receiver before. For example, pressing the Test button will reveal a comprehensive test facility, normally only found on expensive laboratory test instruments: 70  Silicon Chip The spectrum of the demodulated signal is displayed in real time, enabling measurement of the frequency error and modulation parameters of the received signal. Using a signal generator, with the receiver in the SINAD function, you can even measure its own sensitivity. Pressing the Study button on the main panel reveals some of the technology. Demodulation is performed entirely by software, using “Software Defined Radio” technology. Each demodulation mode, like AM, FM and SSB, is performed by applying different mathematical formulas on a digitised IF (intermediate frequency) signal. So the diode and capacitor, for decades used as an AM demodulator, are now replaced by a mathematical formula. This makes the demodulation much more accurate and consistent and not affected by component non-linearities, temperature dependency and aging. The WiNRADiO G313 receivers show the internal structures of these “virtual” demodulators and even allow exploring in detail what’s happening to the signal during the demodulation process (see the AM demodulator image). siliconchip.com.au Here’s a look inside the USB version of the G313. At left is the control section with its PIC microprocessor and AD DSP, while the RF section is shown above right. Left or right-clicking on the block structure diagrams allocates the left or right spectrum to the two respective spectrum analysers. There’s also a vector voltmeter at bottom left, to display the amplitude and phase differences between the two signals. With many conventional receiver functions taken over by the PC, what’s actually inside the box? Above is a look inside the USB-based G313e model. The control board includes an Analog Devices digital signal processor plus a PIC microcontroller running the receiver. The other side, shown above right, is even more interesting. The receiver RF circuitry is divided into several sections. On the left there’s the receiver’s front end, which connects to the antenna. The amplified and filtered RF signal feeds to the mixer and the first IF (intermediate frequency) stage at bottom centre. At top centre is the master oscillator, based on DDS (Direct Digital Synthesis) technology and at bottom right, the second mixer and IF stage. All this produces a 12kHz intermediate frequency output, which is further filtered and processed by the DSP and the host PC. The biggest achievement is running a radio near or even inside a PC – traditionally, a major source of electromagnetic interference. Surprisingly, there’s no trace of PC interference with WiNRADiO receivers but they are not about to reveal to all how this trade secret is achieved. 3.5GHz with an optional downconverter), with fast scans and highly useful scanning-related features like CTCSS and DCS squelch. Its likely that digital trunking decoders are also on their way. In addition to the basic receivers, WiNRADiO produces many software options, such as a number of signal processing and decoding applications – for example, a DRM decoder, which neatly “plugs” in place of the standard “virtual demodulator” window. VHF/UHF WiNRADiO also makes VHF/UHF scanners. The latest low-cost G305e model ranges from 9kHz to 1.8GHz (or even To support their equipment, the company manufactures a range of antennas and other accessories. For much more information, including a full price list, visit the WiNRADiO website: www.winradio.com.au Where from? WiNRADiO G305 is described as aVHF/UHF model – which of course it is – but it covers down to 9kHz! siliconchip.com.au On the WinRadio website you will also find all the other models and the peripherals and options (and there are plenty of those!) Of the models mentioned here, the WR-G313i sells for $1333.27 and the WR-G313e $1599.93, while the PCI version of the G305 is $733.27 and the USB version $866.60 (all prices are plus GST). SC January 2007  71