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Dolby’s many inventions

It was beyond belief to read S Laurence Cachia’s contention (Letters, February 2014) that Ray Dolby was not an inventor. Patents are awarded for inventions, and Dolby had some 50 to his name. Some of these were for the invention of the professional video tape recorder, which in the form of the Betamax and VHS changed how people watch television.

Never were pre- and de-emphasis attributed to him. As Mr Cachia points out, such techniques have been around for years - in fact, well before the 1950s. However, these were almost entirely static systems and not dynamic in their operation. Dynamic compression and expansion systems also have a long history but processed high-level signals, which inevitably leads to audible noise modulation, transient overshoot distortions, intermodulation effects, or a combination of these defects.

Dolby’s breakthrough was to realise that noise is not a problem with high-level signals but with low-level signals that are comparable in level with the unwanted noise. This led to the concept of two paths for the signals to be compressed, with high-level signals being transmitted unchanged and low-levels passing thorough an independent processing channel. This invention, awarded a patent in the mid-1960s, solved the defects and was the basis of his first products which almost immediately resulted in the demise of the many traditional noise-reduction systems and became a standard in the recording industry.

David Robinson CEng FIET
Sebastopol, California, USA


Obstacles to innovation

I was struck by the interview with Kim Chandler McDonald about her new book ‘Innovation, how innovators think, act and change our world’ in the January 2014 issue of E&T (http://bit.ly/1cESY85). I recently visited the National Motorcycle Museum in Birmingham and was reminded that, apart from electronics enabled by the development of semiconductors, almost everything you see on modern motorcycles was tried before the Second World War and most of it before 1930. These were all the creations of innovative individuals whose ideas could be realised with available skills, resources and finances.

Contrast with now; there is no way anyone without many millions of pounds at their disposal could develop a new production motorcycle. This effectively pushes innovation into the hands of large corporations and here we come to the second problem: large corporations tend to be run by professional managers and these are people who are generally ambitious for themselves and their companies, but do not have the urge to create something new.

There is no shortage of innovative individuals in the UK or elsewhere, but there is an environment which means only a very small number ever have the chance to develop their ideas. The key question is not what makes people innovative. but how you make it possible for innovators to vault the much bigger technological, financial and regulatory hurdles that have to be overcome to succeed now compared to 50 or 100 years ago.

Adrian Sharman MIET
By email


Lack of foresight on solar cars

I was disappointed in the lack of vision on both sides of the argument about possible future applications for solar-powered in cars in your February 2014 For & Against debate (http://bit.ly/1idpqSh). I can see two key developments emerging.

First is the use of all-electric cars for city driving, which I was dismayed to see is discounted even in the ‘For’ argument. Whereas I accept that it’s going to be less efficient storing energy in batteries, the whole point is that by moving emissions out of the city, people are no longer exposed to toxic fumes.

Second is local solar generation. To me, the actual ‘breakthrough’ offered by Ford’s concept car is that it could clearly be possible for all cars to be designed with a roof-top solar panel, regardless of their means of propulsion. Then all cars could ‘plug-in’ at parking places and export the collected energy to the grid. Ok, each car wouldn’t generate much power, but just look out onto a car park on a sunny day and see the rows of cars with their roofs shining to see what’s being missed.

Eur Ing Bernard Smart CEng FIET


Source of LED problem identified

Mike Pannell (Letters, March 2014) writes in response to my letter in the previous month’s E&T about the failure of LED lamps in my new home. The builder may have been obliged to fit an energy-efficient product, but the particular LED lamps whose failure I wrote about were an optional extra so presumably they were not legally obliged to fit them; virtually all the other lamps in the house are CFL. Their price seems to be similar to others of similar output and efficiency so I am not certain that it is necessarily the issue either.

Overheating doesn’t seem to be the problem in this case. The lamps are fitted in fire-rated, sealed downlighters made by the same manufacturer specifically for this type of lamp. Being sealed they do not require or have fire hoods. After being on for about an hour the visible face of the LEDs feels hot but you can easily keep your hand on them so is presumably less than 60°C - the rear part of the lamp which contains the control electronics feels slightly warm.

The manufacturer has in fact informed me that the problem was caused by mains surges being higher than anticipated, particularly on new building developments. They have now stopped manufacturing the lamp in question, replacing it with another which contains additional surge protection and more LEDs.

Denis Sharp CEng MIET
Hailsham, East Sussex


Time for risk managers to widen their knowledge

I agree with Ian Griffiths’ comments (Letters, March 2014) following on from my Comment column about risk management in January (http://bit.ly/LWkFlX). I too spend much of my working day reviewing and managing risks for project managers in the manner propounded and so I know there is much work to be done.

However, an unusual quirk has persisted for some years and I think it is time we risk managers tried to put it behind us. Imagine HV power has to be run across a yawning chasm. The scheme developer asks the engineer what is to be done and the engineer says something like “We will need two pylons yay big, capable of withstanding XYZ loadings, MNO metres of cable...” and so on. The developer then asks the risk manager what are the risks of doing that, to which the reply is “I don’t know…what do you think?”, probably followed sometime later by “…and would that be a red or an amber one?”.

Risk managers do not necessarily know a lot about that which they profess to process, and it’s time that we did. You ask a risk manager and too often you get the proverbial time with your own wristwatch.

After 30 years of established practice in the UK, it is about time risk managers knew what the risks are, how they ought to be modelled, and how they can be managed. After all, the money spent on a project is always somebody else’s, and that somebody else may like as much of it back as possible.

Derek Salkeld MIET
By email

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