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An easy-to-build 6-element VHF Yagi for Great Digital TV Reception Do you watch VHF TV? Do you have problems with drop-outs of your favourite stations? Is the picture often affected by intermittent pixellation accompanied by “spitting” sounds? Does your TV give a “no signal” message in periods of wet weather? If you answered “Yes” to any of these questions, the chances are that your TV antenna is no longer suitable for the stations you are hoping to receive. By LEO SIMPSON and ROSS TESTER This screen shot, which we found on YouTube, ably demonstrates what can happen when you use an old (or even a new!) UHF/VHF antenna on a VHF TV signal. It’s almost certainly caused by breakthrough from UHF LTE phone or data signals “swamping” the VHF signal. The solution, at least in VHF-only capital cities, is to use a VHF-only TV antenna! 36 Silicon Chip Celebrating 30 Years siliconchip.com.au Our new 6-element VHF TV antenna is simple to build, from easily-obtainable aluminium tubing . . . but gives a great account of itself in metropolitan areas where VHF TV broadcasts predominate. It should also be adaptable for the relatively few country areas using VHF (except perhaps “fringe” areas). If you still have an old band II/III VHF antenna or worse, a “combi” VHF/UHF antenna, this design should help eliminate interference from other services now using the old TV frequencies. Notice that it has horizontal polarisation, to suit the majority of VHF transmissions (eg, all state capitals). P erhaps you have not realised that in 2014, along with the switch from analog to digital TV in Australia, all VHF metropolitan TV channels were “restacked” into the higher VHF band, nominally channels 6 to 12 (band III). Remember being bombarded with TV ads telling you that you had to retune your TV set? Or the scores of little old ladies calling talkback radio saying “my TV doesn’t pick up ‘Days of Our Lives’ any more . . .” Previous to that you might have been receiving your main TV broadcasts from VHF or UHF channels. Or maybe you were using an old TV antenna which was suitable in the days of analog TV broadcasts but long-term corrosion and different channel allocations have now made those old antennas simply no longer suitable. If you take a drive around city streets you will often observe that many people are still using a VHF/UHF Yagi array (with very long and very short elements), a log-periodic VHF/UHF array or maybe UHF bow-tie array. Since the digital TV “restack” most of these antennas simply are not suitable in metropolitan areas. More information on this digital restack topic can be seen in our Nosiliconchip.com.au vember 2014 issue, in an article by Allan Hughes (www.siliconchip.com.au/ Article/8081). Now over the last few years, you have probably had your TV do a rescan to receive new channels and it has duly picked up the stations you want, plus the regional stations which are typically broadcast from band 4 UHF translators. In that case, you might say, “It works. Why worry?” Well, your old antenna probably does work – sort of. But the fact that the antenna is not cut to suit the restacked VHF channels could explain your occasional reception problems. Another factor to be considered is that the old UHF TV channels that you happily used have now been allocated to 4G mobile phone and data use and that can mean that your TV is now being subjected to 4G LTE interference. This will only get worse – probably much worse – in the future as more and more phone/data services are packed into the old UHF TV band. Overall, if your TV antenna is more than a few years old, there is a fair chance that it is not delivering the optimum signal to your TV set. And while digital TV reception is not subject to the many problems of Celebrating 30 Years the old analog TV broadcasts, such as ghosting, noise, aircraft flutter and is more tolerant of varying signals, once the signal level drops below the “digital cliff” you reach the point where the picture starts to pixellate and then drops out altogether, leaving you with that annoyingly cryptic “no signal” message on screen. That can be really frustrating at the crucial points in your favourite TV series or sports broadcast. The “digital cliff”, by the way, refers to the fact that with digital signals there is very little between a great picture and no picture. It’s either there . . . or it’s not, as if the signal simply “falls off a cliff”. So you probably need a new antenna Do you buy or build? If you are going to buy a new antenna do not buy one from an overseas source. They are unlikely to be cut to suit Australian VHF Digital TV broadcasts. Second point, do not buy a VHF/ UHF array. You don’t need it and it is likely to feed unwanted 4G interference to your set, as can be seen opposite. Even if you want to receive both VHF and UHF, the transmitters are February 2018  37 How we measured the antenna’s gain Elsewhere in this article we mention that this antenna has a gain of 10dBd; that’s +10dB with respect to a standard dipole. But measuring the gain of any antenna is not a simple process and ideally you need to do it in an open paddock with no large objects, buildings or hills nearby. We made do with the parking area behind our building. We used a Hewlett-Packard 8654B RF Signal Generator which covers the range 10MHz to 520MHz and can deliver 1V into a 50Ω load. We matched this to the 75Ω impedance of standard dipole which was connected via 75Ω coax cable. The scope grab at left demonstrates a test in progress. The yellow trace is the output from the RF generator while the green trace is signal received under test. Note that we have applied signal averaging to remove noise. We had to do repetitive tests at different frequencies (for channels 6 to 12). In each case we used standard dipoles for the transmitter and the receiver and the receive dipole measurement was then compared with the same signal picked up by the 6-element antenna under the test conditions. most unlikely to be co-sited, so you need to point the antennas in different directions – ergo, different antennas will be needed. They may also be different polarisation. If you are going to buy a new antenna or have it installed, make sure it comes from a reputable Australian manufacturer. Make no mistake, these Australian companies make well-engineered antennas which will give many years of service and some of their antennas also incorporate 4G LTE filtering as well. Be warned, though, there is a lot of rubbish (dare we say cons?) around – particularly online. (See the physicsdefying model on page 43!). But you can save a significant amount of money by building your own. How much much money? We reckon you can build the antenna described here for less than $65. Depending on where you buy a new antenna, you could save more than half the price. What about recycling your old antenna? A number of readers have suggested this project and one of their cited reasons has been to recycle the aluminium tubing from their old antenna. If you look at the dimensions of the elements of this 6-element Yagi design, you might be able to salvage some of the longer elements from an old lowband VHF antenna. But we don’t recommend it. Those old elements are likely to be heavily corroded rolled section aluminium and not worth the trouble and work in cleaning them up. The 38 Silicon Chip cost of the extruded aluminium tubing in our new design is not high; we purchased ours for under $40 from Bunnings hardware stores. Why bother with that old tatty antenna? Stick it out for recycling at your next council clean-up. By the way, before you contemplate starting this antenna project, make sure that you are in prime reception area for VHF channels 6 to 12. You can do that by going to this website – http://myswitch.digitalready. gov.au/ and feeding in the details of your location. However, this website is not infallible. By far the best approach is to simply to walk around your neighbourhood and see what the majority of antennas are. If you note that the majority are UHF (ie, short elements) pointed away from your city’s primary transmission location, it’s a reasonable bet that there is little or no VHF signal in your location. After all, there is no point in building a VHF Yagi if your main reception comes from a regional (UHF) translator, as it may do even if you live in the heart of an Australian city such as Sydney. For example, in hilly areas such as Sydney’s Northern Beaches, many TV antennas are pointed towards the Bouddi translator on the Central Coast, perhaps 40km away. This is despite the fact that they might be only 10km or so from the main VHF transmitters at Artarmon – but there’s a dirty great big hill in the way! Similarly in the Southern suburbs – many viewers get their pictures from Celebrating 30 Years one of the even more distant Illawarra translators. And what about the recent SILICON CHIP DAB+ antenna? Some readers will recall that we published a 5-element DAB+ antenna in the November 2015 issue (www. siliconchip.com.au/Article/9394). And, given its ease of construction, a few readers suggested that we simply rescale that design to produce this VHF antenna. This turns out to be impractical, mainly because the VHF coverage of this new antenna is considerably wider than that for the DAB channels (which sit in a narrow band smack bang in the middle of the TV channels). Secondly, this antenna is intended for horizontal polarisation while the DAB+ antenna is a vertically polarised design with the mast fixing point behind the reflector. And because we are covering a wider bandwidth we decided to go for a 6-element design which should give more gain over the frequencies of interest and a little less for DAB+ reception. By the way, some VHF TV antennas are stated as being suitable for DAB+ reception as well as TV. That is partly true, but if you are using a horizontally polarised VHF TV antenna for TV reception, its pickup of DAB+ broadcasts will be largely incidental. Having said that, such reception may be quite adequate in your area. Antenna gain A 6-element Yagi antenna like this siliconchip.com.au Fig.1: the 6-element VHF TV Yagi with a plan view (at top) and the assembly detail shown below. should give reception at quite long distances from the transmitter, perhaps 100km or more. However, we have not tested this aspect. We can vouch for the gain figure of around 10dB (as detailed on page 38). You may also wonder “why six elements?” when the DAB+ antenna had five – indeed, you often see antennas with fewer elements or more. siliconchip.com.au The reason is both simple and complicated. The simple part is, the more elements the higher gain, so you should pick up more signal. The complicated part is that you soon run into “the law of diminishing returns” where adding more elements doesn’t really justify either the cost nor the increased size. Six elements, for a wide-band anCelebrating 30 Years tenna such as required for VHF TV, appears to be the “sweet spot”. Tools you will need Most enthusiasts will have most of the tools needed for this project. You will need a hacksaw, electric drill and a vise. It would also help if you have a drill press but you can do without this. Apart from an antenna clamp (UFebruary 2018  39 The reflector and director elements are attached directly to the boom using self-tapping screws. Ideally, all screws, nuts and washers should be 316-grade stainless steel to minimise corrosion. bolt and V-block), no special hardware or fittings are required. Tube cutter A tube cutter is a very handy tool in an antenna project such as this. You end up with smooth square cuts with no swarf. We used a Bunnings product, the Haron Model STC330N. When using this cutter, it is important not to rush the job. Mark the position of the cut on the tube with an HB pencil and then position the blade of the cutter precisely on the mark, with the tube sitting between the rollers. Apply very light pressure with the knob of the cutter and then measure from the end of the tube to the blade of the cutter, to make sure you are cutting to the exact length you want (to be sure, to be sure!) If you have not used one of these cutters before, do a couple of practice cuts on scrap of aluminium tube or plastic conduit, just to get the feel of the whole procedure. You are also likely to find that because the tube is very smooth and quite small in diameter, it is hard to get a grip on it as the cut deepens. Gripping the tube with a rubber kitchen glove makes it a lot easier. Buying the aluminium For convenience we purchased the 10mm round aluminium tubing and 19mm square aluminium tube from the local Bunnings warehouse. They stock the 19mm square tube in 3-metre lengths and the 10mm tubing in 1-metre lengths. So we purchased seven 1-metre lengths of the 10mm tube and one 3-metre length of the 19mm square 40 Silicon Chip The ends of the folded dipole are fabricated using 30mm lengths of aluminium tubing shaped to mate with the upper and lower pieces. They are held together with 50mm long machine screws, nuts and split washers. tube. Total cost: just under $40. You might be able to purchase your aluminium from a nearby metal supplier and in that case, they might cut it to the various lengths you will need (perhaps for a small extra charge?). One drawback of buying tube from Bunnings is that every item you purchase has an adhesive label attached which can be quite difficult to remove. While the label won’t interfere with reception, simply for appearance sake you will need to remove all traces of the adhesive and that can be done with kerosene or eucalyptus oil. Screws & nuts After a few years’ exposure to the elements, many antennas are in a poor state. Aluminium does not “rust” but it does oxidise and its surface becomes very powdery, particularly in seaside areas or in metropolitan areas where there is a lot of industrial fallout. Corrosion will also be a lot worse if you don’t use the right screws and nuts. We strongly recommend the use of stainless steel screws, nuts and washers throughout, whether for machine screws or self-tappers. They do cost more but they last indefinitely. Some readers may wonder about the grade of stainless steel required. We recommend AS316 for best corrosion resistance; it is better than the inferior AS304, particularly in seaside environments. You may find some of the required stainless steel screws are available from Bunnings – however, make sure they are AS316 (the packet will be clearly labelled). Most will be also available from ships’ chandlers (almost invariably AS316) or specialCelebrating 30 Years ist hardware or engineering suppliers. We purchased our stainless steel parts from Bomond Trading Co, in Brookvale, in Sydney. Don’t, on any account, use brass screws. When used to attach aluminium elements these will corrode away almost before your eyes. Nor do we recommend galvanised, bright zinc or cadmium-plated and passivated steel screws (with a gold appearance – they’re rubbish!). In seaside areas, all of these can be visibly corroded with just a few days’ exposure. In rural areas, away from the sea or city pollution, you can probably get away with galvanised screws but the antenna will last longer if you paint it – including all the screws. Starting work Constructing this antenna is quite straightforward. If you have all the materials available you can probably do it in a couple of afternoons. Fig.1 shows all the details of the 6-element antenna. It shows the dimensions of all the elements and the various hardware bits you will have to make to assemble the antenna. At top is a plan view showing the lengths of all six elements and their spacing along the boom. Note that the spacing between the elements varies. Before you start, make sure you have obtained all the aluminium and hardware listed in the Parts List. You will be frustrated if you get half-way through and find you can’t progress further because you lack screws or some other item. Get ’em all before you start. You need to cut the 19mm square tube (the boom) to length and then siliconchip.com.au mark it for drilling and this is where it is quite easy to make mistakes. Double-check everything before you cut or drill! If you are experienced in metalwork and have access to a set of vee-blocks and a drill press, you could substitute 25mm diameter stainless steel tubing which is readily available but quite expensive and quite difficult to cut and drill. Do not use nickel plated tubing – it will rust quickly. Nor should you use stainless steel tubing sold for wardrobe hangers. It is likely to be AS304 rather than the specified AS-316 and will corrode in seaside areas. Centre-punch the boom for all holes prior to drilling. The boom is 1500mm long – see the plan diagram on Fig.1. Mark the hole centre position for the reflector element first, 20mm from one end of the boom, and then work your way along. If you have a drill press which lets you drill all the element holes square through the boom you are fortunate. If not, mark the hole centre positions on both sides of the boom and drill from both sides. If you don’t get the element holes lined up properly, you will have the elements skew-whiff, and that may degrade performance. A few words of advice on drilling is appropriate here. Drilling in thin wall aluminium tubing can be a problem and many people tend to end up with holes that are more triangular than round. The way around this problem is to drill all the large holes (ie, all 10mm holes) under size and then ream them out to the correct size using a tapered reamer. Don’t drill the larger diameters with too high a speed otherwise there may again be a tendency to produce “triangular” holes. If you have a bench drill which allows you to set slower drilling speeds, so much the better. Either way, it is best to drill the element holes to 10mm and then slightly increase each hole with a tapered reamer so that each element is held firmly in the boom. Reaming larger holes Be careful when reaming holes out because it is quite easy to get carried away and then end up with holes that are oversize. Use a scrap piece of 10mm tubing to test when the holes specified at 10mm are the correct size. Each director element and the resiliconchip.com.au flector is held in the boom with a selftapping screw, as shown in diagram A of Fig.1. Drill a 3mm hole at the centre point of each element but only through one side. Don’t mount the elements on the boom yet because the dipole should be assembled and mounted on the boom first. You need to keep a mental image of how the finished antenna will appear. If at any time you become confused, take a look at Fig.1 and the photos showing the actual antenna we built. Making the dipole The folded dipole is made from five pieces of 10mm aluminium tubing: one 810mm long, two short (385mm) and two tiny end spacers around 34mm long. The detail of its assembly can be seen from the diagram at the bottom of Fig.1. The two short tubes, shown as diagram E on Fig.1, are cut and shaped so that they key in with the top and bottom elements of the dipole. Again, further detail can be seen in the accompanying photos. The top and bottom pieces of the dipole are held at each end with a 60mm long M4 screw, together with a nut and lock washer. At the centre, the lower halves of the dipole are terminated on an insulating plate (shown in diagram D of Fig.1). This plate is made of 3mm acrylic (Perspex or Lexan). The dipole halves are each secured to the insulating plate with a 20mm long M4 screw, nut and lock-washer. Terminals for the dipole are provided with two 32mm long M4 screws, each fitted with a nut and lock-washer plus a wing-nut and flat washer. The insulating plate is secured to and spaced off the main boom via a 19mm length of 19mm PVC conduit, shown as a “dipole centre spacer” in diagram F of Fig.1. The top piece of the dipole is secured to the boom with a 60mm long M4 screw, nut and lock-washer. The details of the dipole insulating plate and fixing to the boom can be seen in the accompanying photos. Note that while we used black Perspex, you could use a piece of polycarbonate if that is what you have on hand. However, note our remarks on painting, later in this article. By this time the antenna should just about complete. You need to add the antenna clamp, to enable it to be attached to the mast. This must be just Celebrating 30 Years Parts List – 6-element VHF TV Antenna Aluminium 1.5 metres of 19mm square tubing with 1.2mm wall thickness 7 1-metre lengths of 10mm diameter tubing with 1mm wall thickness* Hardware 1 120 x 40 x 3mm Lexan or Perspex 1 stainless steel or galvanised U-bolt and V-clamp to suit mast 5 8G x 13mm pan head self-tapping screws 3 M4 x 60mm (pan head) 2 M4 x 32mm screws (pan head) 2 M4 x 20mm screws (pan head) 7 M4 nuts 2 M4 wing nuts 7 M4 lock washers 2 M4 flat washers 1 19mm long spacer cut from 19mm electrical conduit or 19mm square aluminium tubing Miscellaneous (sizes/lengths to suit) Mast and wall mounts or barge-board mount (hockey stick style) 300Ω to-75Ω in-line balun (Jaycar Cat LT-3028 plus matching F-connector) Quality 75Ω coax cable to suit (Jaycar WB-2006/9, Hills SSC32 or equivalent) Black plastic cable ties Silicone sealant or Delrin plugs If required as anti-bird strengthening: 2 1.5m lengths 19mm external use PVC conduit * Actual length required is approx. 5.2m if being cut into lengths by supplier Note: all screws, washers and nuts should be AS316-grade stainless steel behind the first director. You will also need a 300Ω-to-75Ω balun to match it to 75Ω coax cable. You can purchase this from Jaycar (Cat LT-3028). Unfortunately, many antenna clamps are sold with a cadmiumplated and passivated finish (which look like a “gold” finish). This is barely adequate for inland areas but rusts quickly in sea air. We may seem to be paranoid about corrosion but since the SILICON CHIP editorial offices are only a kilometre or so from the crashFebruary 2018  41 The dipole insulator plate has wing nut terminals to connect 300Ω ribbon or a 300Ω-to-75Ω balun. The plate is made from Per­spex, Lexan or other acrylic material. The square boom makes mounting easy. ing waves we are very aware of just how quickly metal hardware can rust and corrode. If you can, buy U-bolts and clamps that are stainless steel, as used for car exhaust systems (or boat fittings), as these will last a lot longer. At minimum, choose hot-dip galvanised. Be aware that zinc “plated” fittings are not as rust resistant as galvanised types. Zinc-plated fittings have a smooth bright appearance while hotdip galvanising is unmistakable – it has quite a rough grey appearance. We also suggest that the ends of all the elements and the boom be stopped up with silicone sealant. This will stop them from whistling in the wind. (Commercial antenna manufacturers tend to squash the ends flat for this reason). Better still, you can buy Delrin plugs to suit the square aluminium tubing. These look neater. If you live in an area where corrosion is a problem, it is also a good idea to paint your antenna. If nothing else, the dipole insulating plate should be painted as acrylic material does deteriorate in sunlight (ie, UV). We suggest you leave the antenna for a month or so to weather and then paint it with an etch primer. Finish it with an aluminium loaded paint. Installation When you have finished your antenna you need to carefully consider its installation. There is no point in going to a lot of trouble making it if you don’t install it properly. Try to install your new antenna well 42 Silicon Chip Finally, the 300Ω-to-75Ω balun is secured to the boom using black cable ties. The U-bolt must be sized according to the mast used – we fashioned our own V-block from a piece of scrap angle aluminium as the suppliers didn’t stock them. away from existing TV antennas as these can have quite a serious effect on the performance. Similarly, nearby solar panels, metal guttering, electric cabling, metal roofing or sarking (ie, reflective insulation such as Sisalation) can have a bad effect on antenna performance. And don’t forget the effect of a hot water tank which may be lurking just beneath the roof tiles. Combatting the bird menace Most birds love antennas. You provide them with a lovely vantage point, so they use it. Most birds don’t do it any harm but when heavier birds such as kookaburras congregate on it, they can bend the elements. The two most damaging birds are pelicans and sulphur crested cockatoos. Cockatoos seem to have a particularly mischevous streak – several will bounce on your antenna elements just for fun, to see if they can damage them! To combat really heavy birds, it is best to provide a strong perch about 750mm above the antenna boom. Then hopefully the birds will land on the perch rather than your antenna. Mind you, you can easily replace bent elements, since you will have built the antenna in the first place. An alternative, often seen where large birds are a real problem, is to fit a length of 19mm PVC tube (outside rated for best UV protection) to the outer ends of all elements. This transfers the weight of the bouncing birds over all elements and helps protect them – to some degree. The PVC tubes can be drilled to 10mm (same as the elements) and slipped over the ends. Silicone sealCelebrating 30 Years ant will hold them in place but this also tends to break down in sunlight – a stainless steel self tapper could be a better option. Cockatoos are very destructive and they love chewing antenna cable, baluns and plastic fittings on commercial antennas. You can partly protect the cable if you run it down inside the mast but there is no complete solution. Finally, install the antenna as high as possible above the roof and guttering. If that is a problem, try to install the antenna so that it is at least a half wavelength away from the nearest metallic object such as guttering or roofing. This means a distance of about 750mm away from guttering, solar panels etc. Take care when installing the antenna. Safe working with ladders is particularly important. Take your time and don’t take risks. You don’t want to end up in hospital with a life-changing injury – a common result of handymen working on ladders. Line up the antenna so that it is aimed at your designated VHF TV transmitters. Usually they are in the same general location. You can find out more from http://myswitch.digitalready.gov.au/ Choosing coax cable You probably know that there is a wide range of prices for coaxial cable, ranging from cents to dollars per metre. What’s the difference and why is it important? When it comes to coax quality, price is usually a pretty good guide. Apart from the coax impedance (you siliconchip.com.au want 75Ω), the main criteria you look for is attenuation, or loss. Unfortunately, all coax is lossy – this means that even if you get the last microvolt of signal from your antenna, depending on the quality of the coax lead, at least some of it will be lost on the trip to your TV receiver. You want to minimise that loss. Cheaper coax has a solid plastic dielectric, mid-range has an extruded pattern which is mostly air (hence “air-core”); the best domestic coax has “foam core” dielectric (which has minimum loss) and the outer conductor is not only pretty tightly woven (for minimum loss) it also has one or more levels of aluminium foil surrounding the copper mesh (for minimum loss AND to minimise interference). Attenuation is expressed in dB/100m and increases as frequency increases. Because we’re not talking super high frequencies (~250MHz and less) you can be a bit less fussy in selecting coax. But really, if you’re making this antenna because you need all the signal you can get to avoid the digital cliff, buy the best coax you can afford, within reason. If the length of coax lead-in needs to be relatively long and there are splitters to serve more than one TV set this becomes even more important. When the antenna is mounted on its mast, make sure the coax is firmly secured to that mast (and to the antenna boom) with black cable ties (for best UV protection), otherwise the cable can flap around in the wind. There is nothing more annoying than lying in bed late at night and listening to the cable slapping against the mast! Cable ties are cheap: use them! An astonishing technological breakthrough in TV antennas . . . (!) Every now and then a product comes along that totally rewrites the laws of physics, the laws of electronics, the laws of commonsense and probably the laws of gravity and decency (among others!). Such is the 230 x 102mm TVFox Antenna, available only online, which appeared as banner advertising on a couple of what could only be described as suspect Australian websites. It was pointed out to us by SILICON CHIP reader George B. Thanks for bringing it to our attention! Since then, we’ve also seen variants of these (one called the “TVSurf”) offering similar remarkable (and totally unjustifed) “benefits” – including a testimonial from “William of Perth” who claimed that “this antenna saved him tons of money”. Exactly the same testimonial can be found on other websites. William sure gets around! George wanted to know if these so-called “super antennas” could do what they appeared to claim – that is, pick up subscription TV channels for free. We have to say that this has some of the most creative copywriting we’ve seen in a long, long time. For a start, nowhere do they actually claim that they can receive pay TV channels – but the very name, TVFox Antenna, is misleading in the extreme. They claim that there is a law which forces all cable companies to also transmit their programming on free-to-air channels – and this is what the super antenna receives. Well, we don’t know if such a law does exist in the US (we seriously doubt it!) . . . but we do know there is no such law in Australia. In fact, the exact opposite applies, making it illegal to view subscription or pay TV programs without paying for them! siliconchip.com.au Other claims make for fascinating reading: “designed using discrete military tech” (whatever that means!). “Mount your razor-thin TVFox antenna anywhere – behind your TV or a picture frame . . .etc etc” Oh yeah? Sure, you could mount it there, but would it receive anything (especially shielded by your TV!)? We’d like to see that! “Up to 30 mile range” Not even with a downwind! And notice the “up to” – that means it could be 30-inch range! “Allows you to receive hundreds of free television programs in your area without complicated setups or monthly contracts.” The “antenna” is completely passive. But even if it had an inbuilt (powered) amplifier we doubt it would receive anything, unless you could reach out and touch the transmitter! Maybe. There’s even a photo on one website of it mounted on the side of a caravan – with no apparent connection to the TV set above. Is there no end to the TVFox wizardry? Then there’s the price: $35.74 – not too expensive (if it worked), except that’s in US dollars. So it’s more than $AU45! Oh, but you do “qualify” for $5.00 shipping – only if you order today! (And that’s US$ too!). So if you were to buy one, it’s going to cost you more than $AU50 to find out that you’re not exactly overjoyed with its performance! In a word, it’s a con – and our advice is to run the proverbial mile away if you see one. We’ll give you the URL just so you can have a good ol’ chuckle yourself. But whatever you do, don’t be conned into buying one – no matter how good it sounds! Be amazed yourself, via siliconchip.com.au/link/aaii Celebrating 30 Years SC February 2018  43