Fullscreen HTML5Med Res (??MB)HTML4

How to get Digital TV on your laptop or desktop PC By JIM ROWE Do you want to catch up with TV programs while you work but don’t have the space for a TV in your office or den? Now you can watch on your PC, either in a window or full-screen. All you need is a cheap USB DVB-T dongle. But while they are cheap to buy, they can be a bit tricky to install. Never fear though, we take you through the steps to get it done. Y OU MIGHT HAVE written off those el-cheapo DVB-T dongles you’ve seen on offer from a multitude of on-line sellers. Or you might have bought one and then been thoroughly frustrated trying to install it – we can well understand that! But they are worth the trouble because not only can you watch digital TV on your laptop or desktop PC, many of them are also capable of letting you receive both FM radio and DAB+ digital radio broadcasts. Even more amazing, most of them 12  Silicon Chip are also capable of turning your PC into a wideband VHF/UHF multi-mode communications receiver with a builtin spectrum analyser! They really are a marvel of modern solid-state technology – effectively a digital set-top box shrunk down into a dongle. In this first of a short series of articles, we’re going to explain what’s inside those DVB-T USB dongles or “TV sticks” that have almost exploded into the on-line market over the last year or two. We’ll also tell you how to put them to work – turning your PC into a DTV receiver plus a DAB+ digital radio and an FM radio, using the software that usually comes with them. Then, in the next article, we’ll explain how to use them with other software to turn your PC into an even more powerful “software defined radio” (SDR), capable of both multi-mode reception and “panoramic” spectrum analysis display over a wide range of VHF and UHF bands. Did you read our review of the WINRADIO communications radio in the June 2012 issue? A software-defined radio using siliconchip.com.au Fig.2: three typical DVB-T tuner dongles. These all feature a 75-ohm BellingLee antenna socket but many other dongles come with a much smaller SMB connector, requiring an adaptor cable to connect them to an external antenna. ANTENNA Fig.1 (above): a screen grab of Presto! PVR displaying HDTV channel ABC News 24, received using an ExTV645 USB DVB-T tuner dongle plugged into a Windows XP machine. a DVB-T dongle can provide many of the same facilities at a piffling fraction of the cost! What’s inside? Have we aroused your curiosity? Then let’s begin by looking inside a typical dongle to see what’s there. As you can see from the block diagram of Fig.3, there isn’t all that much. Just two complex chips which do most of the work, plus a few smaller devices which do auxiliary functions like supply voltage regulation, storage of control parameters and receiving IR remote control commands. In many ways, the heart of these dongles is the digital demodulator chip. In almost all of the dongles currently available, this is an RTL2832U device made by Realtek in Taiwan. A surprising amount of circuitry is crammed inside this tiny 48-pin QFN SMD, as follows: • A digital demodulator capable of demodulating a wide range of COFDM (coded orthogonal frequency division multiplexing) signals, including DVB-T television (HD and SD), DAB/ DAB+ digital radio and analog FM radio. The demodulator supports multiple intermediate frequencies (IF) of 36.167MHz, 4.67MHz and “zero IF” (baseband). It also has automatic transmission mode and guard interval detection, impulse noise cancellation, siliconchip.com.au 1.5V REGULATOR BELLING-LEE (PAL) OR SMB SOCKET DIGITALLY PROGRAMMABLE MULTI-BAND VHF & UHF TUNER CHIP (ELONICS E4000, FITIPOWER FC0013 OR RAFAEL MICRO R820T) OPTIONAL RECEIVER FOR IR REMOTE  3.3V REGULATOR REALTEK RTL2832U COFDM DIGITAL DEMODULATOR CHIP (DVB-T, DAB+, DAB,FM) WITH USB 2.0 I/F USB TYPE A PLUG EEPROM INSIDE A TYPICAL DVB-T/FM/DAB+ USB DONGLE OR 'TV STICK' Fig.3: inside a typical DVB-T USB tuner. It’s based on two complex chips: a digitally-programmable multi-band tuner chip and a digital demodulator chip with an IR port and a USB 2.0 interface. Fig.4: inside an EzTV668 USB tuner dongle. The RF signal is directly coupled to tuner chip U4, while U3 is the demodulator. delayed AGC, automatic carrier recovery over a wide offset range, a 7-bit ADC for IF signal level measurement and built-in hardware MPEG-2 PID filters; • A complete USB 2.0 interface engine, supporting full and high speeds with configurable VID information via the external EEPROM; and • An IR port for remote control and wake-up protocols. The RTL2832U runs from a 3.3V supply, so it needs a regulator to derive this voltage from the PC via the USB input. Apart from that, all it needs is a single low-cost 28.8MHz crystal and a small EEPROM that’s used to store its control parameters and ID configuration data. The other main chip inside the dongle is a digitally programmable multiband VHF/UHF tuner chip, shown to the left in Fig.3. This performs all the functions of a complete RF front-end, including a wideband low-noise input amplifier (LNA) with variable gain and autonomous automatic gain control (AGC), a mixer using a fractional-N synthesiser with a fully integrated VCO and loop filter, and a flexible IF amplifier and channel filter with digiApril 2013  13 Fig.5 (below): this Kaiser Baas KBA010003 DVB-T kit comes with the USB tuner itself, a basic infrared remote control, an external whip antenna, a USB extension lead and a software CD. Fig.6: a compact Yagi antenna like this indoor unit may be all you need to get good reception in very strong signal areas. In most cases though, you will need to connect the tuner to a good outside antenna. tal IF gain control and programmable channel bandwidth. Tuner chips There are three different tuner chips used in the vast majority of DVB-T dongles currently available: the E4000 made by Elonics Ltd, the FC0013 made by Fitipower and the R820T device from Rafael Microelectronics in Taiwan. The main differences between these tuner chips seem to be in terms of tuning range and supply voltage, as follows: • The E4000 operates from 1.5V and covers a tuning range from 52MHz to 2200MHz, with a gap from 1100MHz to approximately 1250MHz; • The FC0013 operates from 3.3V and covers a tuning range from 22MHz to approximately 1100MHz; and • The R820T operates from 3.3V and covers a tuning range from 24MHz to 1766MHz. As you can see, the E4000 has the widest tuning range but its manufacturer has apparently gone out of business. So while you will probably be able to get dongles with this tuner chip for some time to come, these are likely to “dry up” when the dongle makers’ stocks run out. Once this happens, dongles containing the R820T tuner chip will probably become the 14  Silicon Chip most popular but note that for the kind of DVB-T/DAB/DAB+/FM work that most dongles have been designed for, the FC0013 chip is capable of doing everything that is needed. Now that you have a reasonable idea of what’s inside a typical dongle (from Fig.3), turn your attention to the picture of Fig.4. This shows the inside of an EzTV668 dongle, currently available on-line for less than $30. The PAL/ SMB antenna input connector is at left, with the RF signal coupled directly into the E4000 tuner chip (U4) just to its right. If you look closely, you can also see an SOT-23 dual-diode “overload protection” device (labelled U7) just below the centre lug of the PAL connector. Above the tuner chip you can also see the 1.5V regulator chip (U1) used to provide it with power. Then at lower centre you can see the 28.8MHz crystal used in the clock oscillator of the RTL2832U demodulator chip (U3), which is roughly midway between tuner chip U4 and the USB type A plug at the right-hand end. Note that U3 is partly obscured by the IR remote receiver (U6), the leads of which mount on the PCB above U3, but bent over so the IR receiver is “looking” upwards. The remaining components to note are the EEPROM (U5), visible just below U3 and U6, and the 3.3V regulator U2, located near the USB plug at upper right. Most of the dongles you’ll currently find on the market will look very similar inside to the one shown in Fig.4. For example, the EzTV645 is almost identical apart from using an FC0013 tuner chip and as a result not having a 1.5V regulator chip. This is also the case with many of the sub-$20 “no-name” dongles and the compact Kaiser Baas KBA01008 (RT). Some of the sub-$20 dongles also lack the IR remote receiver. Now although they all contain much the same innards, dongles can vary quite a bit in terms of external size. Dongles like the EzTV668 and the EzTV645 are among the largest, measuring about 87mm overall in length, 28mm in width and 17mm in depth. The Kaiser Baas KBA01008 is significantly smaller, measuring 65 x 20 x 13mm, while some of the “no-name” dongles are somewhat smaller again at around 58 x 22 x 10mm – much the same size as an older thumb drive. Inside the box So what can you expect to find inside the box, when you order one of these mini marvels and it finally arrives? Well, this can also vary quite siliconchip.com.au Fig.7: the BlazeVideo HDTV player displaying ABC1 on a laptop with a Digital Energy USB tuner. a bit, depending largely on how much you’ve been prepared to spend. If you have spent $50 or more, you can expect to get a package containing all of the items shown in Fig.5. As well as the dongle itself, there should be one of the baby whip antennas shown, with a coaxial lead about 1.5m long fitted with a PAL or SMB plug to mate with the dongle’s antenna input. There will also probably be a small (playing card sized) remote control like the one shown, and perhaps a small USB extension lead like the one visible at upper right. Most importantly, there should be a CD-ROM with the drivers and software you’ll need to install the dongle on your PC. The CD should ideally be a standard 120mm type like that shown (although probably in a paper sleeve rather than in a CD case), as these are suitable for all kinds of CD and DVD drives. But some come with the software on an 80mm CD and these can be tricky to load into a PC with a vertical-tray drive. You may have to copy the files over to a 120mm disk to get around this problem. Of course you probably won’t get siliconchip.com.au all of the above items if you go for a cheaper dongle. For example, you may not get a USB extension lead or a remote control. You may still get one of the baby whip antennas but these are not much use anyway. For best results with virtually any dongle, you need to connect it to a decent outdoor antenna. With some of the really “el-cheapo” dongles, you may not get even a CD with the software. Instead, there may be just a small card in the box, suggesting you download the software yourself from the website URL they provide. And if the software you can download includes a multi-mode DTV/DAB application as well as the drivers, the card may also be printed with the serial number you’ll need to key in to enable the application once it’s installed. Regardless of whether you go for one of the complete kits like that shown in Fig.5 or one of the no-frills sub$20 specials, the main items you’re going to need are the dongle itself and the software. So if the software isn’t included, download it and burn it to a CD as soon as you can. The baby whip antenna can be junked unless you plan to use the dongle to watch DTV or listen to DAB+ digital radio with your laptop out in a park with a good line-of-sight to the transmitter antenna towers. Indoors, you’ll get the best results using an outside antenna – either a standard TV antenna or a wideband omnidirectional VHF/UHF antenna like a “discone”. Installation Now let us move on to discuss installing your dongle’s drivers and application software on your PC. As you might expect, the first step is to install the driver files, which allow Windows to exchange data and commands with the dongle via the USB port it’s connected to. Once the drivers are installed and set up, you can install the application software. Installing the drivers can sometimes be tricky, as we can vouch for from personal experience. All kinds of strange problems can crop up during the driver installation stage and it can be pretty frustrating. To avoid these problems, we suggest that you follow this procedure: (1) If you did not receive a CD with April 2013  15 Fig.8: this screen grab shows several of the files that appear in Device Manager when you install the driver software for a DVB-T tuner with a Realtek 2832U chip (almost all such tuners use this chip). your dongle’s drivers and software, go online and download them from the website shown on the card or leaflet. The files will probably download in a single compressed (zip) file. Once this has downloaded, extract the files and burn them to a CD. If one of the files is an installer or autorun file, make sure you burn that to the CD as well (even if it’s on a sub-directory). Alternatively, you can simply save the files into a folder on the hard disk. (2) Next, plug your dongle into one of the USB 2.0 ports of your PC. Make sure that the port you use is directly associated with one of your PC’s USB host controllers; not one of the downstream ports of a hub. The dongle should also be plugged directly into the port if this is at all possible, not via an extension lead. If you must use an extension lead, use a very short one – no longer than about 300mm. (3) A few seconds after you plug in the dongle, Windows should announce that it has recognised a new device and it will probably fire up an installation “wizard” to find and install what it “thinks” are the correct drivers. Because they almost certainly won’t be the correct drivers, don’t let the wizard spend a lot of time wandering around on the web searching for and then installing some make-do drivers. In fact, it’s quite OK to click on the 16  Silicon Chip wizard’s Cancel button, to send it back to sleep. Don’t worry if it does manage to find and install some drivers, though – these can be replaced with the real ones later. So just ignore any messages it may display, whether they’re advising of an installation problem or of a supposedly successful one. (4) Now insert the driver disk you received with the dongle (or burnt yourself) into the CD drive of your PC. If it has an autorun file, Windows should run this and present you with a menu listing the various installation options. Make sure you select the “Driver installation” option first, whereupon it should proceed to install the correct drivers for your device. Provided there’s an autorun file, the procedure will be the same if you download the software yourself and burnt the files to a CD. Alternatively, if there’s no autorun file and you’ve saved the files to a CD or to a hard disk, check the files (using Windows Explorer) and double-click the one that looks to be the driver installer. It will probably be an “exe” file, perhaps with the characters “RTL2833U” somewhere in the filename, and it may be in a separate folder on the disk. When you find the most likely suspect, try running it as the Administrator. This is especially important if you’re trying to install the dongle files on a Windows 7 machine. (5) Once the correct driver files have been installed, exit from the CD autorun menu if there is one, or otherwise simply eject the CD from its drive and place it to one side for the time being. That’s because you need to check the status of the driver files yourself, before proceeding to install any other software. There’s no point in installing the other software unless the drivers have been correctly installed. (6) Now click on Start -> Control Panel -> System -> Device Manager and click on the Hardware tab. You should now be presented with a dropdown list of all of the hardware items in the PC that are recognised by Windows. And if you look down this list, you should see a subsection just below Processors, with a [+] sign next to a small loudspeaker icon and the label “Sound, video and game controllers”. Click on the [+] sign to see a dropdown list of devices. Somewhere on that list, there should be an item with a name like “REALTEK 2832U Device” or “DVBT/Radio TV Stick”. (7) Right-click on this item and select “Properties”. A window should open displaying the properties of the device. At first, it will probably be displaying its “General” tab, indicating that the device is working correctly. Then, if you click on the “Driver” tab, you should be able to see the Driver Provider as “REALTEK” – as shown in the centre of Fig.8. (8) Next click on the “Driver Details” button, which should bring up yet another window like that shown on the right in Fig.8. If the driver files have been installed correctly, this window will have a scroll-down list of at least four driver files, with filenames like this: BdaPlgln.ax, BdaSup.sys, ks.sys (or ksthunk.sys), RTL2832UBDA.sys and RTL2832UUSB.sys. Note especially the “RTL2832U” sequence in two of the files. By the way, there may be other files besides these four – as many as 19 files in all – but that’s not important. If those four crucial files are shown, the drivers for your dongle have probably been installed correctly. (9) If your dongle has an IR remote receiver inside (like the one pictured in Fig.4), its driver software may include another driver file to allow this to be used. In this case, you should also be able to find a “USB Composite Device” listed down near the bottom of the main drop-down list in Device siliconchip.com.au Manager, under the Universal Serial Bus Controllers section label. If you right-click this device name and select Properties, you should see in the General tab a message to the effect that it’s working correctly. Which is fine but not much consolation if the dongle’s main driver files haven’t installed properly. Troubleshooting So what DO you do if these main driver files are not shown? As you have probably guessed, this almost certainly means that the drivers have not been installed correctly – despite what Device Manager may be telling you. In other words, you are now in troubleshooting territory. The first thing to try is to unplug the dongle from the USB port, wait a few seconds and then plug it into another USB port. Then wait a few seconds again, while Windows does its stuff and hopefully this time correctly installs the drivers. When you go into Device Manager again and check the dongle’s Properties and driver file details as before, the four critical files listed in point 8 above should now be listed. (Don’t ask why changing USB ports can solve the problem, but sometimes it does). If this doesn’t meet with success, the next step is to try re-installing the drivers all over again from the dongle’s software CD. In other words, jumping back to step 4 above – but with a few further steps along the way. You’ll almost certainly find that the driver installer on that disk will want to uninstall the existing drivers first. It will then get you to reboot the PC before it will agree to install them again. So what sounds like a simple reinstall procedure becomes a bit more complicated. Sorry, but we did tell that these things can sometimes be temperamental to install! Hopefully, you should only have to uninstall, reboot and then re-install the drivers once, before you are greeted with all the correct entries in Device Manager -> Properties -> Driver Details, to confirm that the drivers are finally in place. Unfortunately, there is still a possibility that even a re-install from the CD won’t achieve a successful driver installation. If that’s the case, your only option is to find the website of either the dongle maker or their associated software producer and search for a new and/or updated copy of the drivers. siliconchip.com.au Fig.9: BlazeVideo HDTV scanning for TV channels. This scanning procedure must also initially be carried out for DAB+ and FM radio stations. Fig.10: BlazeVideo HDTV playing DAB+ radio station 2DAY. Stations can be selected using either the electronic program guide (EPG) dialog, the control panel dialog or the dongle’s IR remote control. Then you can download these drivers, burn them to a CD and begin the driver installation process all over again, from step 4 above. It’s a bit of a hassle but it may well be your best chance of finally getting a successful driver install. The main software app(s) As explained earlier, there’s no point in even trying to install your dongle’s main application software until the drivers are correctly installed. But once this has been done, you can re-load the software CD in your PC’s disk drive and proceed to install the application software. You should find this process all relatively straightforward, although you’ll probably find that each software application will want you to type in the serial number or password April 2013  17 Fig.11: a live TV screen grab from ArcSoft TotalMedia 3.5 while tuned to ABC News 24, Channel 16. printed on the disk sleeve or download instruction card, as part of the installation process – the usual rigmarole, in other words. There are several different applications commonly supplied with currently available DVB-T dongles. For example, many EzTV dongles come with NewSoft Presto! PVR, which allows scanning the various bands, viewing DTV, listening to DAB+ or FM radio and also recording DTV to hard disk. Another commonly supplied application is Blaze Video Magic 3.0, which allows you to do video and audio file conversion. The Kaiser Baas KBA010003 dongle comes with a single application called ArcSoft TotalMedia 3.5, a very powerful app for scanning the DVB-T, DAB+ and FM radio bands, logging all the carriers/stations and letting you view and/or listen to any desired signal. It Fig.12: ArcSoft TotalMedia tuned to DAB+ radio station 702 ABC Sydney (channel 43). also allows you to record the signal to hard disk and view any EPG that may be available, etc. Many of the low-cost, no-name TV dongles that don’t come with a driver/ software CD but instead ask you to download them yourself provide another application called BlazeVideo HDTV Player 6.0. This seems to be a somewhat later application than Blaze Video Magic 3.0, with various extra bells and whistles (including most of the functions of Presto! PVR). It can also be used to upgrade Blaze Video Magic 3.0, by the way (you just have to “unlock” it using the original serial number/password). These applications all seem to be capable of giving good results with each of the dongles I have tried, providing each dongle has had its correct drivers installed. However, we should warn you that even with the drivers correctly installed, you can still get some weird problems. For example, after I installed the drivers for the Kaiser Baas KBA010003 dongle on my Windows 7 machine, checked them and then installed ArcSoft TotalMedia 3.5, it initially couldn’t find the dongle and refused to proceed. Only when I went through the rigmarole of uninstalling the drivers and then re-installing them again would it find the dongle when I plugged it in and then go ahead and scan the DVBT, DAB+ and FM channels, etc. Another problem appeared when installing a no-name dongle on the same Windows 7 machine, using a driver and software file that had to be downloaded and unzipped. The drivers seemed to install correctly, and I could see the correct files when I went into Device Manager -> Properties -> Use Well-Shielded HDMI or DVI Cables With External Monitors One thing we soon discovered when experimenting with our DVB-T dongles is that interference radiated from a HDMI or DVI cable can virtually wipe out TV reception, especially if using a small indoor antenna. In our case, we were using an 80cm TV set as an external monitor for a laptop (fitted with a USB tuner), with the two connected together via an HDMI cable. Because we were in a very strong signal area, the TV set was connected to a small indoor Yagi antenna (as pictured earlier in this article), while the laptop’s 18  Silicon Chip USB tuner was connected to a simple whip antenna (as supplied). On its own, the TV set worked well with its little indoor Yagi. Similarly, on its own, the laptop and its external USB tuner worked fine from the simple whip antenna. However, when we connected the two together via a cheap HDMI cable and fired everything up, the reception was wiped out by strong interference. This occurred regardless as to whether we were using the TV’s tuner to directly tune TV channels or whether we were using the TV as a monitor and feeding through signals from the laptop’s USB tuner. In both cases, this problem was solved by using a well-shielded HDMI cable, eg, one with quad-shielding. Using snap-on ferrite sleeves at both ends of the HDMI cable also helped clear the interference when watching the TV. Using external antennas with goodquality coax may also have solved this problem, since it’s probable that the interference from the HDMI cable was being radiated directly into the indoor antennas we were using. siliconchip.com.au Helping to put you in Control Control Equipment Temperature Sensor Reads up to 5 Dallas DS18S20/DS18B20 temperature sensors and/or other sensors. Transmits readings out a USB/RS485 serial port to a PC KTA-280 $149+GST Fig.13: BlazeVideo HDTV Player 6.0 tuned to SBS OneHD on a Windows 7 PC. BlazeVideo is one of the more popular playback applications supplied with USB TV tuners. Driver Details. Then when I installed the BlazeVideo HDTV Player 6.0 application and started it up, it seemed to scan the DTV channels correctly and I could bring them all up on the PC’s screen (either in a window or full screen) – but there was no sound on ABC-24 News or 7-Mate, only a fairly loud hum! And there was no sound at all on GEM. I tried re-installing BlazeVideo 6.0 again and then getting it to re-scan the channels. When I tried it out again, the sound on GEM had returned but the hum was still there on ABC-24 and 7-Mate. Another strange problem, this time with my Windows XP (SP3) machine, occurred when I installed the drivers for an EzTV668 dongle and then tried to run ArcSoft TotalMedia 3.5 to see how they would work together. It scanned the DTV channels fine and they were all viewable with their correct sound. However, when I then instructed it to scan the DAB+ digital radio channels, it couldn’t find many of them at all. So I got it to scan the DAB+ band again and then it found them all. Don’t ask me why . . . Success is possible! Just so you don’t get the impression that getting these dongles working correctly on a typical PC is overly difficult, we show a few screen grabs which illustrate that it can be done: siliconchip.com.au First, Fig.11 shows a grab taken on my Win7 machine running ArcSoft TotalMedia 3.5 and using the Kaiser Baas KBA010008 dongle. It shows the picture of ABC-24 News being displayed in a window, along with the various options; Fig.12 shows another grab with the same set-up but with TotalMedia 3.3 now receiving DAB+ radio channel 702 ABC Sydney. For comparison, Fig.1 (on page 12) shows a grab of Presto! PVR receiving HDTV channel ABC News 24 on a Windows XP/SP3 machine, using an ExTV645 dongle. And finally, Fig.13 shows a grab from BlazeVideo 6.0 receiving SBS HDTV on the Windows 7 machine using a no-name dongle. Hopefully these sample shots will be enough to encourage you to get yourself one or more of these dongles and “give them a go”. It can be very worthwhile, despite the risk of hassles if you don’t follow the correct procedure. What’s coming? In the next article, we’ll move on to show you how most DTV dongles can be used with different drivers and software, to turn your PC into a true software defined radio or “SDR”, capable of multi-mode radio reception over a very wide range of VHF and UHF frequencies – and with a built-in spectrum analyser display. So SC don’t miss it! Thermocouple Card Need to log lots of T/Cs? Suitable for use with Labjack U3, U6 and U9 Each card measures the temperature of up to 8 thermocouples. K,J,N,S,T,E,R T/Cs supported. Labjack program free. KTA-260 $69+GST Arduino Inventors Kit One of our most popular kits. Comes with a UNO R3, baseplate, heaps of sensors, leds and other parts to get started in electronics ARD-015 $93.50+GST PID Temperature Controller Great for controlling ovens and furnaces. Controls with auto adaptive PID algorithm. Accepts T/Cs and RTD. Relay and pulse outputs for solid state relays. NOC-301 $129+GST Labjack Digit-TL Is a temperature/light logger which can store up to 260,000 readings, and a battery life of 3 years. Download data via USB LAJ-060 Prices available soon 20A Relay Card Relays can be switched with TTL and open collector signals. Use for forward and reverse control of a DC motor KTB-272 $49.00+GST Hockey Puck LED Light 12VDC and 24VDC versions available with 250 lumen output. It is easily mounted with 1 screw. Great for illuminating cabinets. CSL-9020 $22.95+GST Contact Ocean Controls Ph: 03 9782 5882 www.oceancontrols.com.au April 2013  19