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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.

Comment Re:Health risks? (Score 2) 110

The experts are absolutely NOT divided, and your own post illustrates the case nicely.

When health studies were done on Smoking and Cancer, the adverse relationship quickly became evident.

But studies of the relationship between RF Exposure and Cancer has consistently gone the other way.
In spite of hundreds of detailed tests over many decades, no adverse relationship has ever been detected.

There have been once-off results, but each time they were independently re-tested, the effect vanished.

There is now a vast amount of data across different Frequencies, Power Levels, Modulation, etc.
If there were a relationship (as there clearly is with smoking) it would be easy to demonstrate.

Comment Re:Government Intervention (Score 1) 495

> First, it's polemical to call the LNP ultra conservatives.

This is correct. They should be referred to as Ultra Corrupt Parasites.

And thanks for spewing mindless LNP propaganda. The proposed NBN had years of intense design work, and the actual uptake wildly exceeded expectations.

A google search for "NBN myths" will produce may informative pages, especially those exhaustively documented by Delimiter and Sortius.

Comment Hype and Misdirection (Score 3, Interesting) 140

Have lately been reading everything I can find on Tesla, hoping to find a rational scientific explanation of his "discoveries".
Unfortunately everything so far has been utter balderdash. Just an endless stream of hype.

I had hoped that "Man Out of Time would be better, but sadly it is not.
Cheney seems to be yet another author who has drunk the Tesla Cool Aid.

We hear repeatedly about "Powerful Vacuum Tubes" which turn out to be Geissler tubes,
and how Tesla would "let 100,000 volts harmlessly pass through his body" (no mention that it's high-impedance, and that nerves don't respond to H.F.)
And talk about his secret "High Power Oscillator", which was just a steam-driven linear generator.
Over and over we are told that "Scientists to this day don't know how this was done" when obviously most of it is third rate stage magic.

Hopefully one day a technically literate author will write a book which describes Telsa's work, but without all the hype and misdirection.

Comment They've reinvented CB radio! (Score 4, Insightful) 153

Once there was private peer-to-peer radio. It was called "Ham Radio". But the companies couldn't charge for it, so they made the radios always work through their base stations and called it "Cellular Radio". And of course they removed the peer-to-peer function.

But wait, now it's back! (in a way that can be monetised of course).

Comment Re:Scrap all the rules (Score -1) 104

BTW, encryption is already permitted (in the ham bands) in many countries. The only catch is that the encryption must be via a publicly disclosed method.
There are many encrypted ham standards, PSK31 WSPR, WSJT, MAP65, Hellscriber, etc, etc.

The main reason (for public methods) is to prevent commercial organisations taking advantage of the generous Amateur Radio provisions.

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