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VISIONNews and information from around the industry See Page 3

Vision Products are flying the flag for UK installers and specifiers! Working with new UK electronics partner, Precision Manufacturing Ltd, Vision are helping to boost the British economy with products built and designed for use by UK installers - and creating more UK jobs.

But why is having PML as a manufacturing and design partner here in the UK important? When you look at what’s involved in modern electronic manufacturing, the advantages become clear.

Precision AssemblyWhilst some manufacturers still use old-fashioned components that stand up on legs, the best RF signal components use Surface Mounted Technology. In fact, many leading edge RF products come from the demanding mobile phone industry. SMT components satisfy the increasingly smaller and ultra-low power requirements in next generation hand-sets. Intricate SMT devices often measure less than 1mm across, so the delicate task of placing them on the PCB is best handled by automated machines with microscopic optical inspection systems. But this is just part of the story. For long service life, great care must be taken when soldering. The quality of a soldered joint is dramatically affected by the time spent soldering. Performance and service life can be reduced if a component overheats during assembly. PML uses automated “pick and place” precision machinery that flow solders to achieve accurate placement and

Precision manufacture in the UK “Hand-built” somewhere overseas

behind the scenes with this summer’s biggest blockbuster

If Digital Switch Over (DSO) has taken place nearby, you may have already come across the dreaded transmitter channel Overlap problem. If you’re looking for practical advice or need to prepare in a pre-DSO area - read on!

A National ProblemRecent information from DigitalUK warns that an increase in the power of DTT transmissions post-DSO will result in 92% of the 26M homes in the UK facing some form of Overlap with a number of transmissions competing with each other. Problems in Granada, Wales and West have produced lurid headlines, and indications are that it will be worse in landlocked regions like Central.

Typically, post-DSO Overlap could result in a digital ready TV or Freeview box tuning into channels from a non-local region, perhaps showing “No Signal” or with intermittent break-up on some channels. All bad enough by themselves, but as DSO rolls out countrywide it will get worse. Southern coastal regions are anticipated to be particularly badly hit by foreign European signals swamping us as they follow the UK lead in adopting a common broadcast standard.

Understanding OverlapFreeview receivers are usually programmed to regularly auto-scan or after an automated instruction, often following channel lineup or transmitter frequency changes. By tuning “upwards” from Ch21 to Ch68, lower end UHF signals will be found first. The channel

found may not necessarily be the right one, and may even be in a language you don’t want! In some cases lower frequency channels are from the right region but are from a weaker distant transmitter that can’t provide consistent quality signals, or overlapping signals can overload amplifiers in tuner causing distortion and signal break-up. What To DoDigitalUK recommend a few work-arounds. Possible solutions are:- - Manual Freeview box tuning- Remove the aerial during tuning

and replacing it during auto-tune- Channel Sort or Favourites.

Unfortunately, Overlap “sticky plasters” will need re-applying every time a new channel is added or the Freeview receiver is moved. With every single receiver in a household at risk this could become a very time consuming and costly problem.

Prevention is always far better than cure so when changes do occur, call-backs won’t be generated. We recommend:-- In extreme cases, add a grouped

band pass channel filter to eliminate out-of-band signals.

- Grouped Log Periodic, rather than wideband Yagi aerials, reducing levels of unwanted signals below tuner threshold, maximising signal reception and impulse noise reduction.

- An attenuator to ignore weaker channels.

A Log Periodic SolutionThe Log Periodic design is ideal to help combat Overlap. With each

d i p o l e tuned to a different wavelength, each element works as:- - A dipole, collecting signals from

a narrow frequency range- A director, focusing lower

frequency signals onto dipoles behind it

- A reflector, protecting the dipole(s) in front of it from unwanted signals.

With a “natural impedance” of 75Ω, signals are transferred to the 75Ω coax cable with minimal loss and reflection, just what’s needed to keep signal integrity and minimize impulse noise. This means smooth performance across the desired frequency range and very high directivity. Impulse noise is dramatically reduced as the design is grounded to the mast.

The range of Log Periodic aerials best suited to solving overlap problems are three of the models in the Vision range. Installers can choose from the Group A 40 element V10-40A1 or V10-20A2 and for Group E the 34 element V10-34E3. For weak signal areas or applications requiring exceptional directivity and noise immunity, use the wideband STEALTH. It outperforms every other benchmarked wideband aerial on the market and is the only log aerial to meet or exceed all 4 wideband Aerial Benchmark categories.

getting over-lap

flying the

industry leader partners with six figure uk manufacturer

product range built especially for use by uk installers

r&d housed in midlands hq

...continues on page 3

The V10-34E3, a greatLog Periodic problem solver

de-mystifyingde-rating

highly trained

staff

space

There’s been much debate about the use and abuse of performance figures for amplifiers, aerials and other devices. The first article in a series simply explains why these numbers matter.

Amplifier Maximum OutputA rating in dBµV, decibels above one microvolt, often describing maximum singla level before distortion occurs. In an audio product, distortion makes sound horrible - for an RF product this signal interference causes analogue picture break up and freezing in digital systems. The best way to avoid these problems is to understand them.

Vision uses the i n d u s t r y

s t a n d a r d

definitions for product performance, EN50083-5 (IMD3-60) for terrestrial gear and EN50083-3 (IMD3-35) for satellite systems. For ease of comparison, these figures are shown for a load of two equal channels.

Because there will almost always be more than two channels in a system, you will need to De-Rate the maximum level to compensate for the actual number of channels and avoid distortion. Only then can maximum output signal levels be worked out.

Uh?OK, imagine your van is rated to carry 2 one-ton bags of sand. If you wanted to load up with 4 bags of sand, you couldn’t put the same size bags in the back without wrecking your suspension - you’d need 4 half-ton bags instead. It’s the same with amplifiers. As you increase the

number of channels, you have to reduce the maximum level per

channel.

Simples!Well, it would

be really

simple to work out, except signal levels work on a logarithmic decibel scale. Doubling signal power roughly increases levels by 3dB, and halving it reduces the signal level by 3dB. So when an amplifier rated for 2 channels is used for 4 channels, the maximum power for each channel would need to be halved - a drop of 3dB in signal level. This means if the spec says the maximum output is 80dBµV (for 2 channels) signals must be below 77dBµV for 4 channels and below 74dBµV for an 8 channel system.

In The Real WorldIn reality, life is more complex. Signals never arrive at exactly the same level or come in neat multiples of two. Don’t forget that every signal going in to the amplifier, even the unwanted ones, generate a load. Remember also to make allowances for adjacent channels.

To help you we have produced a De-Rating Reckoner. Imagine five equal channels. Look for the “5” entry horizontally across the page, and with a ruler draw a line down until you hit the curve underneath. In this case

you’ll De-Rate by about -4dB.

You can use this as the basis for more complex

calculations. Take a situation

you may come across

during DSO, of five channels at one level, plus another six channels, -15dB down.

The five channels are easy to work out at -4dB. On the vertical axis, -15dB matches with “64” on horizontal axis, so it’s about 1/64

th the power of the stronger channel. Six of these would still be only 6/64

ths of the power, hardly anything in practical terms, so we’ll allocate -1dB just to be safe. Our total De-Rating figure works to be 4dB+1dB, giving a total of 5dB.

More SuggestionsFilter out unwanted channels as much as you can do. Look at satellite switches, mastheads, TV boosters, active splitters, not just the obvious amplifiers. With a struggling system, needing just a small level increase, it may be cheaper to add a good filter than replace a launch amplifier. The better the filter, the more unwanted signals are removed giving the system “breathing room”

Unfortunately some manufacturers only give an input rating rather than the output that Vision quote as well, but De-Rating can still be worked out. With maximum input of 40dBµV and maximum gain of 30dB, maximum output is 40dBµV+30dBµV or 70dBµV. This same is true in reverse. A variable gain amplifier will probably have more “headroom” because the attenuator will decrease the signal before it gets to the amplifier circuitry.

Vision had a call recently from a customer with what seemed to be a very odd problem. Vision like a challenge, so set to work...

The customer installed Vision V5 5-wire IRS in a development some time ago, and as instructed by the landlord planned to extend the system in the next phase in a separate building a distance away from the head end. The IRS extension worked well with signal levels all fine and level at each wallplate. Tenants enjoyed TV and satellite in the original building, and the installer relaxed in the knowledge of another job well done. Meanwhile, the landlord began to market the new block….

A few months later, tenants reported that TV reception stopped working in the evening - and you could pretty much guarantee it would be just as a big football match kicked-off! This didn’t seem to make much sense, so the installer made a site visit to pin down the problem. Sure enough, once evening arrived, protection circuitry

and the red overload light activated on the V5-100T launch amplifier and the predictable tenant complaints began.

Help!The next morning, he was on the phone to Vision asking “Have you got a special football filter in your switches?” We grinned and explained it’s not a standard feature, and got our tech boys on the job straight away.

Expert OpinionIn a multi-building system, we advise that installers and planners always assume mains power in each building is on a different phase. In some cases, electrical regulations prohibit DC connections between buildings as different earth potentials may exist. Ideally, a locally powered dish and head end should be installed in each location, but there are times when this is not the best solution, such as when shared CCTV video is to be distributed via a coax link between buildings.

What seems to have happened is that the IRS got sick when a tenant

in the new block put a voltage onto the subscriber line by switching on a satellite receiver in the evening. As this was a different phase, the potential difference was greater than the system was designed for and the amplifier protected itself turning off the signals in the process. The result was lost TV in both buildings.

Problem SolvedIt’s essential, if not a legal requirement, to electrically isolate trunk cables between buildings and power systems independently, something the new Vision V5-025 Galvanic Isolator is designed for. It will safely pass RF TV and satellite signals whilst preventing harmful voltages and earth potentials passing from one building to another. Don’t forget you’ll need one of these low cost devices on each of the trunk cables and appropriate earth-bonding in each block. Remember, they are isolators, so no DC switching will pass for polarity switching – these are for fixed polarity trunk cables, not subscriber drop cables.

If you are building a head-end for a large system but you are restricted on space, what about using the Earth-Connect earthing rods and connectors to reduce the footprint? With four V17-063B Rods and eight V17-063 Connectors you can stack one multiswitch above another, offsetting the top to allow access to the controls. This not only saves space with a stable fixture but also meets earth-bonding requirements. Neat!

Piers Johnston has been a key member of the Vision team since the early days. While some people in the industry may call him an “expert”, he believes that there is always more you can learn - which is why he’s just finished studying for another qualification.

He’s now been awarded an NVQ Level 3 in Signal Reception that formalises his knowledge of larger multi-dwelling systems, the equipment used, alignment & level setting, earth bonding and system planning. It even covers Health & Safety risk assessments.

Congratulations Piers!

Now everyone knows that you know what we knew you knew anyway.

“On the day he passed his Level 3 NVQ, Piers knew his exceptionally long legs would come in handy!”

get yourself in trAining for summer

As sick As A pArrot?

We’re committed to making sure that installers get the best from the wide range of Vision products. Training is a big part of this.

Courses are normally held at our Northampton facility, but if you have enough delgates and the right venue, we can run anywhere in the country. Here’s a small sample of the courses we’ll be running this Summer;

Introducing IRS To Installers(full day course)- What does an IRS Network do?- C/N, setting up and alignment- The right aerial, the right dish?- Understanding the multiswitch- Using the right taps and splitters- To amplify or not to amplify?- Five powering options- Earth-bonding & galvanic isolation- An introduction to system planning

The Surveyor’s Guide To IRS(full day course)- What does an IRS Network do?- Where do you lose the signal?- Best sites for dishes and aerials- Less cable or more cabinets?- Multiswitches, taps and splitters- To amplify or not to amplify?- Five powering options- Earth-bonding & galvanic isolation- An introduction to system planning

Finding The Right Aerial(half day course)- What does an aerial do?- Basic aerial designs- What to look for when buying- Benchmark Standards- Managing post-DSO overlap- Fitting and alignment

Contact us direct on 0845 017 1010, or talk to your local Major Distributor, to find out more about these training courses and the others on offer.

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A parrot earlier today

...the final frontier

looking goodsetting new standards in distribution amplification

flying the prevents component overheating. This assembly is optically inspected and will be right first-time, every time. This simply cannot be achieved by hand soldering and manual placement.

Screened Compartments“Lift the lid” on modern masthead amplifiers and filters and you’ll notice a big difference between a Vision product and any others - a complex and intricate metal “screening can” divided up into smaller compartments. Electro Magnetic Compliance regulations recognised that any electrical device could radiate a signal. Increasing numbers of devices in the home and workplace mean cross-interference and product failure would be more likely. Screening with what looks like a tin box is now commonplace, trapping any amplifer generated interference.

Screening also prevents external interference which may disturb TV

reception. You’ll probably recall lines or patterns on a TV years ago when a motorbike or car passed by. Digitally, this type of interference causes major picture and audio disruption that is greatly reduced by a “screening can”.

Vision lead others with screened compartments inside the main can, isolating circuitry elements. This improved interference rejection and performance removes out-of-band signals, such as TETRA, much lower noise plus stable pictures and sound in low signal areas previously thought impossible. To date, no other manufacturer has come close to Vision’s outstanding performance and reliability.

Better Components for Low NoiseIn addition to state-of-the-art automated assembly, PML and Vision use superior components from the design stage onwards. Most mastheads use either bi-polar transistors or Field Effect Transistors to amplify the signal. Older bi-polar semiconductors have typical

noise figures above 2dB whereas a standard FET can be around 1dB. Vision Gold mastheads feature next generation FETs with extremely low noise so that a 13dB masthead has a noise figure of typically 0.8dB. No other masthead on the market has managed to come anywhere near this astonishing performance since launch a few years ago.

Better Design means Flatter GainSome pretty crude mastheads are sold in the UK, many developed for countries where high gain rather than low noise is important. With over 1000 transmitter sites in the UK and signal levels about to be increased significantly, higher gain may actually become a disadvantage - but flatter gain and lower noise will never be.

It’s well known that Log Periodics provide the flattest gain by receiving signals at the same proportions rather than artificially adding gain to some channels. This could mean TVs see certain channels very well and others less well. However, even the best Log Periodic has signal variation across the band.

The situation is made worse if a sloped gain aerial is used with an inferior amplifier, many of which have flatness as bad as ±3dB! This means potentially 6dB between the weakest and strongest signals in addition to 3dB of slope from the aerial, making your install more difficult than it needs

to be. Rest assured that Vision Gold mastheads are designed, manufactured and tested to deliver ±0.5dB across the band.

Testing for SuccessPML use automated assembly to enhance quality. Testing ensures that every single production unit meets the original high specification. Gain across the band will conform to rigid minimums, maximums and flatness. Filtering is individually optimized ensuring correct out-of-band rejection without affecting in-band performance. Noise levels will be at defined levels. Impedance matching is tested on inputs and outputs. Finally Power Consumption is checked.

Getting the BestThere’s simply no better way to build and test these products, and we think the UK is the natural place to build them. Thanks to installers specifying high performance products, Vision is now the UK leader for quality mastheads. We think it’s quite fitting that this means jobs are being created in the UK, especially in these tough economic times. Vision and Precision Manufacturing Ltd will continue to invest in UK manufacturing in the coming years and proudly fly the flag for Great Britain.

Vision announce the UK’s first professional grade IR distribution amplifier with diagnostics this Summer - the V65-200 series of VisionLink™ distribution amps

Looking and feeling like a pro satellite switch like the Vision V5MP, these new amps won’t be confused with a DIY shed product. That’s good news as we all know the sort of customer who wonders if he’s just paid for you to fit something in his loft he could have got down at B&Q himself! This is the real deal.

Take a Closer LookThe differences are much more than skin deep. With some very smart features, your life will be quicker, easier and less hassle.

For a start, there’s a highly visible LED next to each outlet port, showing there’s DC voltage available to drive a VisionLink™ (or other brand) of “Sky eye” IR link and connected to individual port protection circuits. If an individual output shorts, the protection circuits quickly switches off the power to that port leaving all other ports operating normally. This brings a number of benefits:-- Component Protection. If output is connected to a TV rather than via a Visionlink™, it may look like a short circuit to the DC voltage. Most other

products will continue to try and power the short, driving a little DC current down the coax via all the connectors into the tuner or isolation components of the TV. Though most amps will reduce current this is best avoided completely. Until the reset switch on the V65-200 amp is used, all DC power to the port is shut down and won’t be re-applied.- Fault Finding. Intermittent connection problems in drop cables, wall plates and patch leads are very hard to trace. On a V65-200, when an individual LED goes out it becomes easy to identify where the problem lies even with no marking or colour coding.

Big Choice, Little Boxes The new range is a bit more varied than you might be used to. The simplest unit starts with just 2 outlets, and then we step through 4, 6, 8 and 12 outlets and finish with the top of the range 16 outlet model. But even the largest unit is extremely compact, because V65-200 series outlets are positioned on both sides of the robust housing. Ideal for tight corners in a loft!

We’ve also opted for more capable electronics that allows operation over longer distances. With two inputs on all models – one for radio DAB/FM and one covering UHF TV - plus 10dB

of UHF gain, you can be confident that these units will comfortably cope with even the largest systems. There’s also 2dB of gain built into the return-path to make sure that remote control signals sent via a VisionLink™ eye from anywhere on the system will arrive back at a Sky box at full strength.

Professional OptionThese sturdy amps are every inch part of a quality installation. Features like F-connectors on inputs and outputs, an easy-to-use 6mm² earthing post, fully screened metal housings and clear label specifications mean that no matter what the size of the job, these compact units will deliver time and time again. Try one on your next job and we’re sure you’ll never want to use another product again.

Oh - and did we mention they’ll cost you the same - or even less - than many DIY retail products?

if you have a problem,if no-one else can help,

maybe you can hire...

graham philipsZ isThe Planner

The quiet one, transforming the client’s brief into a clearly laid out system plan with a full parts list. Don’t worry, you might have scribbled it on a fag packet - but Graham’s on the case.

“mr philipsZ”

stephen baden isThe Designer

This guy’s surrounded by more test equipment than you’ll find anywhere else in this industry. What he doesn’t know about RF isn’t worth knowing about. He’s solving tomorrow’s problems today. Every day.

“sparks”

from this summer

there is no plan “t”

Compact distribution amps from

Vision’s new V65-200

series

continued from page 1

Vision Gold 13dB Masthead16

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Vision

Brand X

Amazingly flat Vision gain where a budget product struggles

Quality Vision design with screened compartments & precision re-flow solder

An internally unscreened foreign build with hand-placed solder blobs

alan bone isThe Controller

He’s patenting ideas, registering new designs, implementing regulations as well as keeping an eye on our published data and doing some planning, But he’ll never be too busy to help if you’ve got a query.

“digit al”

VISION Products (Europe) LtdUnit 1 Redbourne Park, Liliput Road, Brackmills Industrial Estate, Northampton NN4 7DT

Tel: 0845 017 1010 Fax: 0845 017 1011

landlord power?more problems!

it’s A steelnew cabinets with time &

money saving features

novision’s easy-read guide to irs without communal power supplies

Cabinets come complete with two sets of locks, earthing post & heavy duty mounting brackets

Delivering Phantom™ power

With growing IRS demand, installers are likely to run into powering issues. Vision has an easy guide to help cope with difficult situations where there’s no landlord power supply funded by the building owner and charged back via rents or service fees to tenants.

Is Solar Power an Option?.It is possible to power an LNB, satellite switches and aerial amplifier from “alternative” energy systems. Since current solar panels operate at around 50-70% efficiency during hours of bright sunshine, the UK’s dismal summers and grey winters may result in frequent call-outs if you rely just on solar power charging

battery systems. Further barriers are regular battery top-up schedules and environmental legislation involved in battery disposal. These systems can work, but high costs, poor reliability and the similar battery issues are off-putting.

An alternative is to use a line-powered (or phantom-powered) multi-switch to power the LNB and aerial amplifier. Rather than rely on a central power supply, a small amount of power is drawn from tenants’ dwellings or satellite receivers. Since all users contribute the few pennies of electricity needed to operate the system, no mains installation or

electrician charges. In comparision to solar power this is substantially more reliable.

Stick to the Sky™ SpecificationSo how do you make sure you are choosing a reliable and compliant phantom powered system? Always plan for the worst case and assume only one resident is using a Sky receiver. BSkyB advise staying below 90% of the current STB capacity, typically 320mA.

That’s an awful lot for a typical block of 8 flats wanting Sky+ or Sky+HD. You could be asking it to:-

Amplify the satellite signal to overcome a 16-way split

plusAmplify the terrestrial signal to

overcome a 16-way splitplus

Drive a Quattro LNBplus

Pre-amplify the terrestrial signal in poor reception areas

Make Good Kit ChoicesA 16-way splitter typically loses up to 14dB of signal. A multi-switch like the Vision Phantom™ delivers good signal levels even on longer cable runs without extra amplification. Unlike less able products, Vision Phantom™ amplifies terrestrial

circuits allowing signals to travel further down the coax.

Many phantom powered systems work perilously close to their limits. Drawing up to 220mA, an average Quattro LNB takes a huge chunk of the current “budget”. Launched this Summer, Vision’s V85-401QT super low-energy Quattro LNB features low noise, advanced filtering, high isolation between polarities and low power consumption of just 90mA!

For dwellings with no satellite receiver, use the 18V from a genuine Vision V75-185 PSU. With a fair wind you might get a lower spec 12V PSU to work, but at the risk of problems. Pictures can be lost for a time if the 18V sent from a single STB struggles to power the whole system and momentarily drops. This can be misinterpreted as as a polarity change by the switch.

“No Signal” errors can also be avoided with the right kit. A momentary power drop to 0v can occur when an STB switches between 14v and 18v, creating a draw on others in the system. The 500mA supplied by the V75-185 is capable of operating an entire system on its own.

So Do the MathsPhantom 516RPS 150mAV85-401QT + 90mA 240mA

80mA below the limit!

IRS is all about reliability. Call-backs cost time, money and reputation. Cutting corners or experimenting on your customers can your profits. Choose reliability every time!

If political events of the last few months have taught us anything it is that not all “cabinets” are the same (sorry!). The new Vision V45 range of steel cabinets really does prove the point that getting the right cabinet is vitally important.

Available right now from all good wholesalers these IP65 rated weatherproof steel enclosures are revolutionising the industry with a unique combination of great features that make the whole process of installing much more straight forward, saving you time and crucially money.

With system installers in mind you can protect your work from weather, vandals and “helpful” amateurs who can’t resist fine-tuning things after you have left. The real excitement has been generated by the stack of well thought out features the come delivered with every cabinet.

These cool grey cabinets help you deliver a professional looking, secure and weatherproof result every time. They are available in four sizes to suit almost any situtation;

V45-400 (400x400x200mm)V45-600 (600x400x200mm)V45-800 (800x600x200mm)

V45-1000 (1000x800x200mm)

We believe that these offer something unique and have been granted a Community Design Registration (No. 001215651-0001) with a Patent Application. Cabinets are available across the UK right now in all good wholesalers.

Our innovative cable membrane(shown inverted for clarity)

The 13mm ply back board is not only coated in a clean pale grey colour but the grid pattern makes alignment or centring the equipment a doddle and helps you deliver an end result that looks 100% professional.

The exterior quality pre-fitted ply back board is not a rough rectangle but is thoughtfully shaped with recesses to allow you to grip it whilst removing or fitting without taking the skin off your knuckles. This common sense approach is a feature of many products across the Vision range.

To locate the board into the cabinet Vision have cut angled slots (not small holes) making it easier to find the mounting bolts “blind”. Whether or not you are at the top of a ladder, holding the backing board in place whilst finding the right spanner to tighten everything up can be a pain so Vision helpfully use wing-nuts.

Another unique feature is the cable entry. No holes are drilled into the chassis exposing uncoated metal to the elements. No shopping around for a collection of the right size glands. Simply remove the elastomeric membrane and place it on a flat piece of wood to drill a hole for each cable. Use a sharp wood drill bit 6 to 6.5mm for single coax, 20mm for 5-core for best results.

Knuckling down to the job

A professional finish every time

Easy to fit wing-nuts