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Comment Re:Does it explain the sucky battery life? (Score 2, Informative) 248

This is true. And it's actually a battery saving technique. The phone will attempt to transmit and make a connection with the weakest possible transmission power possible. If that fails, then it kicks up the power and tries again.

You have it backwards. Phones don't transmit when they are looking for a tower, they LISTEN. The tower has MUCH more transmit power than the phone does, so when you are out of range, it is likely you can hear the tower, but it can't hear you.

And when the phone does try to make initial contact with the tower, it does so at the highest possible power level. The tower then tells it to reduce the transmit power, if it is too high.

The tower is smart about receiving initial contacts too. It reserves some time slots for such attempts, in effect saying "if you're trying to get in touch with me, do so NOW". It has to do this because of the propagation delay - it doesn't know how far away you are, and doesn't want you to transmit all over a time-slot that is reserved for someone else.

Comment Re:So pathetic (Score 1) 111

Wrong. The P-N junctions in thermogenerators contain no silicon whatsoever. In early thermogenerators the junctions were created by using two different metals, and later thermogenerators use bismuth telluride in place of one of the metals. See the Wikipedia page on "Thermogenerator" for more detail.

If you want a valid argument on environmental costs, compare the environmental cost of using a thermogenerator to the environmental cost of the batteries it replaces. Balance that against lifetime: thermogenerators can last decades, as demonstrated by their continued operation as the power source in both Voyager spacecraft.

However, in THIS application, you are probably right about "destroying" power: they will consume more power in manufacture than they put out during their lifetime.

Comment Re:Why 2-legged? (Score 1) 151

Wheels require a bearing, and lubrication in a vacuum is difficult. Legs can have a bellows over each joint, and you can have an "atmosphere" inside the bellows. Lubrication suddenly becomes a lot easier when your lubricant doesn't boil off into space. Vacuum welding of parts stops being a problem too.

Of course, then you are limited by the fatigue life of the bellows. However, if you don't flex the joint, the bellows don't fatigue. Infinite life, provided you don't use it.

Comment Re:Reasonable cost? (Score 1) 212

Make sure there is a linux live-cd inside the case, securely fastened and protected from dust (like in an envelope, with the envelope glued down). Include a piece of paper with instructions on how to make the computer boot from CD. Have the initialisation script on said CD start up a remote-management client.

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