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Got an analog TV set? You’re going to need an HD Set Top Box! If you currently have an analog TV set or a digital projector and don’t want to change it, you will need a high definition set top box to watch HD TV broadcasts – now and more importantly in the future. By LEO SIMPSON W ith that in mind, we purchased a Tevion TEV8200 HD STB from our local Aldi store. This is one of the cheapest HD STBs currently available and has all the features that you are likely to want. With a recommended retail price of $119 (including GST) and occasionally available on special at $99, the Tevion HD STB is hard to go past. It is quite a bit larger than typical SD STBs and is quite heavy to boot. Its front panel has six pushbuttons to control the various on-screen menus, to select channels and control volume. But after the initial setup, there is no need to ever use the front panel controls. The rear panel is of more interest because the number of video output connections is impressive. In fact, the array of connectors on the rear panel is likely to be quite daunting for any non-technical user. It has the standard male and female coax connectors for the antenna input fly lead and an output to VCR, TV or whatever. To connect an analog TV, there are RCA sockets for composite video and L & R stereo audio, S-video and component video. Most analog TV sets will just use the composite video output (yellow socket) and the left/right stereo outputs (red & white). If your set only has a The TV Channel Manager screen shows the channels that are available together with a preview of the channel selected, in this case ABC HDTV. Note the availability of the D44 data signal channels. 14  Silicon Chip mono input, use the left audio (white) output. In the (these days most unlikely) event that your analog set does not have audio/video (A/V) inputs, you will need an RF modulator to connect to the standard antenna input. Both Altronics and Jaycar Electronics have suitable RF modulators. For connection to home theatre receivers, there are two digital outputs, one via a SPDIF coax (RCA) socket and one via a TOSLINK (optical) connector. Having the two options is good since you may find that one of the digital inputs in your home theatre receiver This screen is a program guide showing what is available over most parts of Sydney, including the D44 Datacast channels. The latter include weather, federal parliament, a TV buying channel, a Christian channel and so on. siliconchip.com.au is already in use and so you can use the alternative. In case you were wondering, SPDIF stands for Sony/Philips Digital Interface. TOSLINK is a registered trademark of Toshiba Corporation and hence the origin of the name: TOShiba-LINK. For connection to a PC, there is a DVI socket. For connection to a PC monitor, you can use the VGA RGB/ HV D socket, together with the L & R audio outputs. For connection to an LCD or DLP video projector, you can use the component video or HDMI digital outputs. Of course most good projectors will also take composite video, S-video or RGB/HV inputs but if you want highdefinition pictures, you need to use the component video or HDMI signals. Setting up the Tevion TEV8200 is straightforward. First, you need to select the video output which you have connected to your TV, projector or whatever. To do this, you press the FUNC button on the remote control twice within four seconds and this brings up a fourdash display on the STB’s front panel readout. You then press one of the coloured buttons to select the output: RED for PAL (ie, analog TV); GREEN for VGA; YELLOW for Component Video and BLUE for DVI/HDMI mode. You can also use the Left/Right buttons to select the video resolution you want such as 1080i (interlace), 720p (progressive scan) and so on. siliconchip.com.au For best picture from a video projector, it is desirable to set the STB’s output video resolution to the “native” video resolution of the projector, although most of the better projectors will do a pretty good job of scaling the signal to suit. Most HD projectors will also automatically recognise interlaced or progressive scan signals.    Once you have set the video output, you can ignore the front panel display of the STB, as it will display all the information you want via the video screen. The next step is to get the STB to scan all the available channels. You can do this manually but it is far quicker and easier to just let the STB get on with it. Afterwards you can decide to get rid of channels you don’t want, rename them, change their order or whatever. Inside view of the Tevion TEV8200: note the large and complex PC boards and the large number SMDs and electrolytic capacitors. The electros look as though they might have been hit by a mini-tornado, don’t they? March 2008  15 Initially though, just let the STB do it. It will then come up with a display of all the channels available in your location, together with their signal strength and quality. It is here that an STB can demonstrate surprisingly good results. In my setup I have a 4-bay UHF antenna with direct line of sight to Sydney’s North Head (Mosman/Manly) translator and it gives good reception of the existing analog stations (ABC, SBS, 7, 9 & 10). The Tevion picked up the equivalent digital channels as you would expect, plus a brace of digital datacast channels (D44) which are available only in Sydney at the time of writing. I certainly did not expect to pick up the D44 channels – they must be coming in from the side of the UHF array. (For a signal coverage map, see www.dba. org.au/uploads/images/NSW_Syd_ Datacast_coverage_map.jpg As well, it also picked up the Prime and WIN digital and HD channels from Wollongong, about 85km to the south of my location on Sydney’s northern beaches. These latter channels do come and go at my location and it is possible that the intermittent reception was a case of summer-time tropospheric “ducting”. Suffice to say that there is no equivalent DX (ie, long distance) reception of UHF analog channels from Wollongong and SBS and ABC digital signals didn’t make it either. The really good point about digital TV reception is that, provided the STB can pick up the signal, the picture is rock steady with no sign of ghosting or noise. Even if you have pretty good analog TV reception, the transition to digital is a revelation, with the picture quality the same as obtained from a standard definition DVD, depending on your video signal connection and the quality of your monitor. The Tevion STB has two further benefits when the signal strength momentarily dips, as it may do on the weaker signals. Instead of the annoying random pixellation of the picture, the whole picture freezes and then a panel may be displayed with the message “No signal”. Furthermore, there are no loud zaps or cracks from the speakers as the sound drops out. Instead, the sound is muted, without any clicks. Nor are there any clicks when the sound is restored. Having written that, I noted than when watching weak HD broadcasts the picture does sometimes also suffer from momentary freezing and pixellation. Still, it is not as severe as I have noted on other (SD) STBs. For my checks I connected the Tevion to an older Panasonic 68cm analog TV (TC-68P22A) and a Panasonic AE700 LCD projector. On the analog TV, via the composite video connection, I had the satisfaction of seeing HD TV broadcasts without problems, although the picture quality was no better than noise-free PAL, as you would expect. Via the Panasonic projector and the component video connection, the pictures are first class, even on standard definition. In fact, I must admit, after watching the very large pictures This is what usually happens during loss of signal. The picture freezes and you get a panel with the message, “No signal”. Occasionally the picture becomes pixellated. 16  Silicon Chip available via an HD LCD projector, I still have problems coming to grips with the excellent picture quality – it still seems too good to be true. For one who has experienced the limitations of black and white and then PAL colour TV reception, the results from digital TV are a revelation, as noted above. In spite of that, it must be said that the picture quality from most of the supposed HD programs is apparently no different from that of SD broadcasts. You only have to see the outstanding quality of the so-called “HD loops” broadcast by some of the commercial networks to see the dramatic difference with true HD. I should also note that the Panasonic AE700 is not a “true HD” projector. True HD requires a picture resolution of 1920 x 1080 pixels or better. Aspect ratio Another point of interest with the Tevion is that you can select the picture aspect ratio to be shown on your TV set or display. You have three choices, 4:3, 16:9 or Panscan. This is perhaps the biggest disadvantage of watching digital TV on an analog set with a 4:3 picture tube; no matter which aspect ratio setting you choose, the results are less than optimum. If you choose 16:9, you will have black strips at top and bottom of the picture, just as you do, for example, with current analog broadcasts of ABC and SBS news programs. If you choose 4:3, you get a 4:3 picture, within a black rectangle – not very satisfying. On changing channels, you get this electronic program guide for a few seconds. Lately, though, we have noticed increasing instances of “no information” . siliconchip.com.au The rear view of the Tevion TEV8200 shows a comprehensive array of video and digital output connectors. Note that DVI and HDMI connectors are included; essential if you are to get the best picture from LCD and DLP projectors. And if you chose panscan, the whole screen area is filled but inevitably, you lose the sides of the broadcast picture. Oh, well...never mind. As an aside, the commercial networks have yet to standardise their program and advertising content and the aspect ratio can vary between 16:9, 4:3, letter-box and so on. It is also very annoying for people with 4:3 sets when watching sports – the 16:9 format means that sport scores often cannot be seen. Also on the negative side, sound quality appears to be only average and there is a fair amount of high frequency “frizzle” and a low level tone which is probably related to the switchmode power supply. You have two choices for sound quality by the way, although the modes are limited: stereo (MPEG1/2) via the audio outputs or Dolby AC-3 via the SPDIF connection. Presumably, the AC-3 mode would be free of highfrequency frizzle but we did not test it. The remote control provides 20-level adjustment and muting. Incidentally, all the screen shots of the Tevion STB shown in this article were taken with a 6-megapixel digital camera (Fuji Finepix S6500fd) from the Panasonic analog TV mentioned above. One of the problems with taking these shots was the strobing effect between the TV scan rate and the camera’s picture update, together with the inevitable Moire patterns evident because of the interference between the camera’s CCD pixel structure and the vertical slot makeup of the TV screen (perhaps this might have been reduced if the shots were taken at siliconchip.com.au maximum file size). A consequence of the strobing is a tendency to get a light band through the centre of the picture, in spite of using a slow shutter speed of 1/15 second. So while some of the various off-screen shots may look fairly poor, the actual picture quality was generally very good, as already noted. Incidentally, all of these picture problems could have been avoided if I had taken the screen shots using the Panasonic projector, particularly if its “freeze frame” feature was used. But this would have defeated the purpose, as I wanted to show what is displayed on a typical analog TV set. Interestingly, I found that the Aspect Ratio selection from the Tevion STB over-ruled the aspect ratio control on the Panasonic projector – not sure why that happens. One aspect of digital TV that is not well-known is that digital radio services are available from ABC and SBS. Also available in rural areas is the Mytalk datacasting service. See www.mytalk.com.au/NewDesign/ Pages/Datacasting.asp Finally, the Tevion offers the ability to view subtitles via teletext and it has a selection of simple video games – perish the thought! Inside the box A look inside the box shows the Tevion HD STB is far more complex than typical standard definition STBs. It has a large main PC board which is packed with surface mount devices and a surprising number of electrolytic capacitors. I have to say that QC in assembly was a bit lacking: the electros are soldered in every-which-way but vertical! The switchmode power supply board is also quite large, again with a number of electrolytic capacitors. Interestingly, while the Tevion is double-insulated, it is fitted with a three-core mains cord and moulded 3-pin plug. Power consumption of the Tevion is listed as 20W. We measured power consumption at 14W, dropping to 12W on standby. Why the small drop? Surely, standby power should only be a watt or two? This means that the Tevion should be switched off at the power socket when not in use. All settings are saved in non-volatile memory when the power is off. A USB socket on the rear panel is included for software upgrades and interestingly, the operating system is Linux. The main chip is an ATI Xilleon X210H. Conclusion If you don’t intend purchasing an HD TV set in the near future, you should consider purchasing an HD STB such as this Tevion TEV8200. For a relatively small outlay, you will get the immediate benefits of much better picture quality and a great range of TV programs. Sure, it’s not perfect and its standby power use is on the high side but the pictures outweigh the drawbacks. And to save power, all you have to do is turn it (and anything else that goes to “standby” with a remote control) off at the power point. Our recent series of articles on power usage showed just how wasteful standby power is – and how much (power AND $$$) you can save with the simple step of turning things off! SC March 2008  17