John Curl's Blowtorch preamplifier part II

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Yes. The 'millenium bug' was certainly real, but overhyped. The reason it was overhyped is that it was the only way for engineers to get the attention of politicians and managers (via journalists) so they took their heads out of the sand for a while and planned (and funded) some action.
Indeed it was real. I was also one of those who spent man months on updating a working system to a new version which could handle processing of dates across that boundary line of time. If nothing had been done it would have been disaster for the organisation, clients would have been roaring blue bloody murder, because their reports would have been nonsense ... it had to be done, cost plenty to do the conversions, and run parallel operations over extended time frames to ensure complete agreement in results. The computer industry took it very seriously, in time, hence no noteworthy glitches ...
 
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Which App does one have to download for that ?

No app -they just sniff out the signal that your cell uses to maintain contact with the network, apparently.
Or maybe they just ping you as the network would.
Come to think of it, maybe they use the 'phone's internet connection - you could shut that off of course.

Jan
 
Scientists can't even find a missing commercial airliner, with satellite imagery, radio pings and millions of dollars.
Yes, it is unbelievable. I cannot understand why the GPS position of all the planes are not recorded in real time each and every second. But that is the fact: Out of the radars of the airports, the planes are lost in the space.
 
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As well as the datas recorded in the "Black Boxes" that no one can ensure they will be safe or found in case of a plane crash ?
Why so late in our 21th century, computers (and cloud) based ?
With some GPS navigators like Waze, all the movements and position of my car are recorded and analyzed in real time by their server to inform other users of the circulation's conditions. And there is more cars than planes.
 
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The reasons they are not publicized and used by civilian authorities in cases like this would take us afoul of the forum no-politics rule.
Are you suggesting, without politic, that the U.S. government (as an example, because it is probably the most technologically advanced nation ) would know perfectly the position of the lost aircraft and leave desperately seek relief for months, spending millions of dollars and leaving bereaved families without even send an anonymous phone call to the civilian aviation authorities ?
Hard to believe !
 
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..... since there are two versions of you - a physical one and a virtual one. Companies have been using specialist services that build an internet profile of a potential (and current) employees for quite a few years and they can tell a lot about you -your political pursuations, habbits, who you are lilely to associate with etc. .....

That explains why the headhunters never answer my calls.....caller ID... :(

I think it is better regarded as a lag than an inversion. You have a distributed filter. The current inside the material is both attenuated and phase shifted. The net current is the integral of the current density.

I believe you are incorrect. Go back and re-examine the graphs. During the fall of the positive first time ever current(he distinguishes it as the solid line, dashed is steady state), the surface currents invert. IT does so as a consequence of the slew of the current, which at that point is negative (NOT as a result of a lag as you assumed, there is no physical history yet of the inverted current). So the negative current density is a consequence of the magnetic field energy being converted to eddy currents during the collapsing phase. This is not consistent with the skin effect approximation of planar E/M waves being driven into the surface.

If you integrate the total area, the negative current subtracts. This will give an erroneous estimate of dissipation of the system.

Also, the internal inductance of the system as a consequence of integrating the shells of current both positive and negative, indicate quite clearly that the internal inductance is heavily dependent on the instant in time of the driving waveform. Again, the exponential skin depth approximation does NOT consider this, but all authors of E/M books I've researched already point out that the skin effect linear approximation is only valid for skin depth >> wire radius, and skin depth << wire radius.

For the region where they are close, again, all attempts to linearize the models fail miserably in accuracy. The simple linear models do not account for the transport current's variation in radial density nor eddy dissipation vs radius.

Don't get your panties in a bunch however, this effect in speaker wires and audio currents/frequencies is so low, I'm not sure even I could measure it. But I am confident that eventually, we'll see the author I pasted from a paper being quoted for ad copy in some speaker runs.. sigh..

Did you find this paper?
jn
 
Esperado, forum and common sense rules please :)
Well. May-be it was a little provocative, yes, but common sense, certainly.

Despite what believe the supporters of the 'great conspiracy' and what the scenarists of James bond movies want to make believe, things are most of the time more simple and trivial (even ridiculous) than we imagine, and power of big brother limited..

It is not a question of politic or even technology. If many 'offices' in the world are able to follow-you on the street with satellite cameras, and read your car number from the sky, they only can look at what they seek in real time...and if the satellites they can use are free for them at this time...
Micro and macro model.
All networks administrators know the pain to find something special and unexpected on request in a big database.
For this plane, and i'm sure of that, no satellite were recording images of this part of the ocean with enough resolution at the time this plane crashed. or a single image, somewhere, lost between billions of similar ones.
Just bad luck, and a compilation of little failures like all the plane crashes.

Now, the subject was: While private commercial companies are tracking and recording our individual behaviors, positions of planes with hundreds of passengers aboard are not tracked yet for their security, despite the technology allowed-it from decades. It is something amazing, but real. Like often, we have to wait a big noise in the medias to see the things improved.
 
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A few comments:
- your personal data is tracked because someone makes money off of it; not so for tracking planes;
- as Jacco noted, hi speed objects are less simple to track (except by mil radars but these are far and few between and not particularly interested in commercial jets;
- tracking planes over sea is not easy (Google 'radar clutter').

Jan
 
To go back to our domain, i believe no transistor manufacturer is able to produce *a* transistor with precise characteristics. Only able to produce million of them, and find some samples in them responding to the request.
Our amplifiers are build with a mix of incredibly sophisticated technology, based on the Quantum theory, and very middle aged trial and error designs.
And this is all the pleasure and beauty of this activity. Knowledge and smell.
 
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