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Comment Re:Navigation wqy bqck then (Score 1) 106

There is a routine way to measure Longitude on land which uses some external method the establish the exact time of local noon (eg a lunar eclipse, the transit of Venus, the position of Jupiter's moons), then this information is conveyed (by mail) to the nearest observatory, who can then calculate your position for you.

I recall that this was one of the reasons that astronomers made long voyages to carefully measure the Transit of Venus or Mercury.

Comment Spread Spectrum (Score 1) 142

It is fundamental that a well designed Spread Spectrum transmission is essentially the same as wideband noise, and unless you know the code, is un-crackable.

The Spreading Code itself provides the Encryption (eg via Gold-Codes, or if necessary, via a one-time pad)

The idea of Extra Terrestrial Intelligence using Spread Spectrum is not a new idea. It dates back to the '40's when Spread Spectrum was first declassified.

Comment Re:Don't say that this side of the Pacific... (Score 5, Informative) 75

As always there were many who help develop a given technology.

Many companies marketed ISB band links, but it was Lucent (owned by NCR) who developed the WaveLan system which evolved into the various WiFi standards we have today.

But it was the Australian CSIRO who patented the modulation scheme (FFT with multiple carriers) that was the foundation technology for WiFi.

Comment Re:Nothing special... (Score 1) 80

Wow, nasty much? Along with the half-wit up-votes.

Actually, the OP is correct:

- The term "Axle Assembly" refers to the axle housing as well as as the actual axles.

  - And if it doesn't have axles, how come the wheels don't fall off?

  - And having hub motors adds essentially nothing to it's off-road ability. It could as well use chains, hydraulics, or more conventional shafts and universals.

It's essentially no different to a conventional 4WD, except that the pivot points are above the center of gravity.

Comment Re:RC Rules (Score 1) 110

> I bet you could count on 2 hands the number of people who were hobby flying RC aircraft in your city

Utter rubbish.

When I was a kid (rural Australia, in the 1950's and 60's), RC modeling was a huge hobby. Most of us progressed from Free-Flight, to Control Line models, to RC flying. Not to mention RC boats and cars.

Admittedly the gear was rather basic with only one or two channels. We could only dream of owning the expensive USA gear, hence our homemade Valve (Tube) Transmitters, Receivers, servos, tone decoders, etc.

Surely you've seen the many DIY magazine articles and books from back then?

Comment Re:Living off the grid (Score 1) 281

Have lived of-grid for over twenty years. Have a large battery bank, but only 600W of solar cells. That runs my house and workshop without ever needing to run a generator. The only concessions needed are no electric heating or cooling. I rely instead on good insulation and wood heating.

The main barrier to Solar living is the typical American mentality, "I'm not going to live without my Air-conditioner/Clothes-dryer/Electric Heating".

To my mind, frugal living gives many bonuses beside the ability to survive without the ever more expensive (and unreliable) mains power.

Comment Re:Not actually batteryless (Score 1) 110

Because if the Cell Phone didn't "Leak" it wouldn't work at all.

This "leaking" as you call it, is the Cell phone actually transmitting useful Radio Energy.

And in the case of a GSM phone signal, the RF envelope is heavily Amplitude Modulated.

The problem is that cheap electronic junk has poor "Radio Immunity" causing it to act as a radio receiver when it should not.

Comment That's the way that GSM phines operate (Score 1) 110

Because that's the way that GSM phones operate.
In order to achieve Full Duplex operation, it receives for half the time, then transmissions for half the time.

These transmit data bursts result in a deeply Amplitude modulated RF envelope.

This is why you hear Brrrp, Brrrp when you put your GSM phone near a pair of cheap loudspeakers.

Comment Google is becoming useless (Score 4, Interesting) 375

This sounds like a great improvement.

Some years ago if I searched for a data sheet for an Electronic Component, I could rely on a direct link to the PDF in the first hit or so.

Now however, any worthwhile result is often many pages down the list. The first page or two are full of "Are you searching for xxxx? We don't have that right now, but here's a great way to earn big dollars!!".

Google is so badly scammed that I usually don't bother. I hate to say it, but even Bing is better now.

Comment Re:Not actually batteryless (Score 2) 110

For what it's worth a FM Crystal set on VHF is most definitely possible.
(do a search on "FM Crystal Radio", there are many articles).

And of course a Crystal Set can pick up AM signals from a cell phone. It's trivially easy.

The trick of course is the Inverse Square of distance Law. When you are close, the signals are so much stronger.
And in the near-field the relationship is Inverse Cubed which makes it even easier.

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