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Comment Re:Better transistors? (Score 1) 308

On the other hand, designs with less energy loss will open up the potential of higher speeds, once the techniques get refined.

No and here is why.

For a CPU of a given complexity, a specific area is needed for transistors, routing, etc in a given process. If the process density goes up, then the power has to be lowered to maintain the same power/area because the area largely determines the thermal resistance and for the past few generations, high performance CPUs already operate with the junction temperature as high as is reliable. So power is proportional to chip area and higher density processes yield smaller chips so power has to be lower.

You can see this trend in Intel processors since about the Core2. The highest power models all have a power rating proportional to area and since more recent models are smaller, they have lower power ratings.

This is also why stacking memory on top of logic is not going to happen for anything except low performance logic.

Comment Re:Electronic Engineer Here (Score 1) 220

The use of non-volatile SRAM which has an embedded lithium cell might be considered this when it is not replaceable. A lot of test equipment built starting in about 1990 has this "feature" even if it was implemented by replacing the previous solution of an external lithium cell, low power SRAM, and backup circuits while using the same printed circuit board.

More recent is the problem with aluminum electrolytic capacitors which have a well understood and predictable wear out mechanism. I have older ATX power supplies which have lasted well past their warranty date but newer ones from specific manufacturers reliably fail just out of warranty.

Comment Re:Why this is special (Score 1) 133

My understanding was that topping up a lithium battery was good; it was a more complete discharge that added wear cycles to it. Obviously this isn't true forever but better than lots of charge and deep discharge cycles.

The irreversible damage occurs at both high and low voltage. If the battery capacity is limited to between say the 80% and 20% charge points, then the total energy delivered for a given decrease in capacity goes up so many shallow discharges are better than fewer deep discharges if they occur toward the middle of the capacity curve. Maintaining the battery charge state closer to 100% lowers the useful lifetime (lithium metal plates out?) but this effect is usually small compared to capacity lost do to general use. It would be more important in standby applications.

Supercapacitors also degrade at high voltage; in their case, increasing the voltage by 0.2 volts lowers the operating life by 10 times. Offhand I do not know what the equivalent specification is for lithium secondary cells.

Comment Re:Check the Focus! (Score 1) 117

For Hubble someone forgot to account for change in shape of the lens due to gravity, because, you know, it's a complicated thing to make.

The problem with the Hubble mirror had nothing to do with gravity.

The custom precision null corrector used during the figuring step was assembled incorrectly. When the standard null correctors used for the initial grinding showed spherical aberration during final testing, they were ignored as being too inaccurate compared to the custom precision null corrector.

Comment Re:wire wrap cable testing (Score 1) 169

A continuity tester would not have worked well because the response time for the human to test all N^2 connections and look at the continuity tester was too long.

I am not sure what continuity tester you have experience with but all of my digital multimeters going back 20+ years produce a tone in addition to a reading on the display and respond within milliseconds. Running the test lead along a string of contacts or pins and listening works fine with them.

Comment Re:WTH (Score 1) 90

Do you have a citation for this?

I think you might be referring to the CALEA requirements which also apply to WISPs. There is no CALEA requirement to maintain the records you suggest however most ISPs do for other reasons and if you provide voice over IP services, the FCC does require location data to support E991. With or without these records, CALEA requires ISPs to aid law enforcement in identifying and wiretapping targets.

Comment Re:TWC will try (Score 1) 90

That is the situation some WISPs have faced in contested areas. The incumbent wired ISPs buy up tower space preventing the competing WIPS from using it and then flood the ISM bands with generated traffic. Canopy gear was popular for this because it uses TDMA instead of CSMA. More direct measures like jamming critical nodes with a flood of traffic on the same channel from a directional antenna at long range are also used.

Comment Re: Already here - it feels unfair to some (Score 1) 412

A firearm does not have to inflict a death to successfully protect the user and a majority of self defense firearm incidents result in either no death or the firearm not even being fired.

As for the difference between acquaintances or family members and strangers, most interactions are with the former rather than the later and the term acquaintance is used very very broadly in crime measurement.

Comment Re:Deniers? (Score 1) 507

I made my post just to point out that thermocouples and thermisters are unsuitable for precision temperature measurement compared to RTDs and that has been the case for decades. But even with their complexities like cold junction compensation and lower accuracy, thermocouples are preferred to RTDs because of their temperature range and price. RTDs have the advantage of at least an order of magnitude better accuracy. They do make "precision" thermocouples by using purer metals but accuracy is still limited by the cold junction compensation and they cost as much as an RTD solution making them only suitable for when you need increased accuracy outside of the temperature range where an RTD can be used. I was not addressing the use of RTDs 100 years ago but I can.

The need for a stable reference resistance is not unique to RTDs and it is hardly a problem; we have been building resistors out of Manganin which are stable over temperature and time for more than a century using the same construction techniques used to build RTDs. I have a pair of ESI impedance bridges which use wrapped wire (probably Manganin) over mica resistors (ESI made these in house) built in the 1960s which are still accurate to 3 or 4 significant digits. It is not real clear how accurate the bridges are because they are as good or better than any 0.1% resistor (or capacitor) that I have tested them with and that is about the limit of their precision anyway.

An accurate RTD thermometer without amplification or stable voltage or current sources could have been made 100 years ago using a balanced bridge, Kelvin Varley divider, and galvanometer. As a matter of fact, my old ESI impedance bridges work in exactly this way for DC resistance measurements; no stable reference voltage or current is needed and no amplification is needed.

This would have been pretty cumbersome way to measure temperature because you would need to balance the bridge for every reading and consult a chart to remove the non-linearity of the RTD so if you only needed 0.1F resolution, a mercury thermometer would have been better if only because of its ease of use in an adverse environment.

Comment Re:Drones will be the real threat at a large event (Score 1) 60

I would think that if something like that were to happen, it would have happened already.

That is a great argument up until the first time that it happens and there has to be a first time.

That this *hasn't* happened in spite of how obviously vulnerable these places are to even the typical American mass shooter, let alone some group with any kind of advanced planning and better weapons leads me to believe it ain't gonna happen, either. Like maybe the threat isn't nearly as real as the media makes it out to be, or maybe it's actually harder than you think to pull it off.

The threat just is not that real but eventually someone is going to use or try to use a UAV in a terrorist act.

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