STUDENTS of the delicate art of putting the past into the best possible light should read 鈥淟egacy of the X-ray Laser Program鈥� in Energy and Technology Review, the house magazine of the Lawrence Livermore National Laboratory in California. It describes the 鈥渓egacy of new technologies for industrial and medical use鈥� left by one of the old Star Wars projects.
The original idea was to use a nuclear explosion to power an array of X-ray lasers in space, which would destroy Soviet nuclear missiles in flight. Its advocates, notably Livermore physicists Edward Teller and Lowell Wood, had visions of a weapon no bigger than an office desk that could obliterate the entire Soviet intercontinental ballistic missile fleet.
The X-ray laser programme has gone the way of the Soviet Union, but the cheery Livermore article assures us that plenty of valuable spin-offs remain. Of course, the article does not mention how much the US spent on the programme, a sum believed to run into billions of dollars. And it is equally evasive about the cause of the project鈥檚 demise, blaming it merely on 鈥渧arious technical difficulties鈥�.
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Those who follow Pentagon fiascos may recall that in reality the project imploded after a group of scientists from Livermore announced that Teller had given misleading information to the government and had been 鈥渙veroptimistic鈥� about the project鈥檚 feasibility (This Week, 10 March 1988).
IN THE US, youthful vandals have grown tired of spraying paint on other people鈥檚 cars and found a nasty new trick. They hit the front bumper with a baseball bat. The shock triggers the car鈥檚 air bag sensors, so the owner returns to a car which has its front seats filled with a balloon. The bill for repacking the bags is around $300.
We learnt of this from an electronics company which is developing microchips that can tell the difference between shock waves caused in a crash and shock waves from the impact of a baseball bat. Rather nervously, we asked why they didn鈥檛 save themselves all the trouble and just connect the air bag trigger circuit to the car鈥檚 ignition, or to a weight sensor that detects when someone is sitting in the driver鈥檚 seat. In that way, the air bag would not be triggered unless the car was being driven, or was at least occupied.
The electronics engineer responded with a barrage of impressive talk about 鈥渄ialling鈥� the latest microprocessor algorithms and crash impact shock wave signatures into the microchip. Could it possibly be that no one has bothered to consider the much simpler and cheaper answer?
WHEN a cable TV company digs up the street, it costs several hundred pounds for each home it passes. The team buries ducts or pipes, then pulls through copper coaxial cable. The idea is that it will be easy and cheap to add fibre-optic cable later when the time is right to build the long-awaited information superhighway. Engineers will simply open up the manholes, push rods and ropes through the pipes and pull through new cable.
In Feedback鈥檚 area of London, the local cable company is currently burying ducts. They are plastic tubes, like toughened rainwater pipes, laid in shallow trenches and buried under heavy paving stones. Will these tubes still be free of obstruction in a few years time, making pulling through a fibre-optic cable easy? Or will they have been crushed tight by the weight above?
No one will know for sure until it is too late. Certainly British Telecom builds its telephone ducts deeper and stronger than these cable companies. There is a joke now going around BT. Want to put a cable company out of business? Just get a couple of heavy lorries to mount the pavement.
SUDDENLY everyone wants to use e-mail and the Internet, so we are thrilled to pass on the answer to a technical problem we have been struggling with for the last couple of years or so.
Modems bought in Europe may unaccountably refuse to work with American systems (for example the giant MCI/Tymnet network). They connect, but then just sit stubbornly dumb. This is nothing to do with data speeds, it is far more subtle than that. In fact, two quite different gremlins are conspiring. Even the networks鈥� own helplines have been unable to help.
The first gremlin is that European modems work like fax machines and send bleep 鈥渃alling鈥� tones down the line while they are waiting for the e-mail system to answer. American systems often don鈥檛 like this. They get confused and switch off. The trick is to put a circumflex (藛) at the end of the telephone number you want the modem to dial. This stops it sending bleeps.
The second gremlin is that European modems use fancy systems called MNP and LAPM to speed up transmission, but American systems often don鈥檛. Again, they get confused and disconnect. The trick is to disable this fancy feature on the modem by entering the command AT\N0 before dialling the number.
Feedback gathered these two bits of advice from two different modem makers. Each had tried out their own trick on some systems but not on others. Feedback has found that used separately, the tricks are of limited effectiveness. Used together, however, the chances of success are much higher. The luck involved in discovering this must surely be on a par with winning the National Lottery.
LASER pointers that project red spots onto screens in lecture theatres have become commonplace over the past few years, but recently Feedback saw a prominent physics professor proudly wield a laser pointer that shed green light.
The pointer is one of a handful custom-built in Japan, but it is not just a display of technological one-upmanship. The professor is colour-blind and can鈥檛 see the red spot produced by ordinary laser pointers.
SOME years back, the Heath Electronics Corporation built a robot called 鈥淗ero鈥� which it flew around the US entertaining visitors at trade exhibitions. Hero was a rather large and delicate piece of machinery who was transported in a box and required his very own airline seat.
However, this created problems with airport security personnel, who tended to be suspicious of large boxes containing peculiar equipment. The solution, Feedback is told, was to program Hero to respond when his box was opened. Engineers experienced no difficulty getting him onto planes once he had learned to say: 鈥淚t sure is good to be out of this goddamn box.鈥�