So the poster is correct. It is a 217Hz RF pulse with about 500uS pulse width. Cell phones use an electric field antenna which produces a high near field electric field that decays at 1/r cubed, and a propagating electromagnetic field that decays at 1/r. It is most likely the near field electric field (capacitively coupled) that is consequently demodulated by any non linear components in your speaker amplifiers as the PA (Power Amplifier) in the phone changes power level. Even though the electronics industry is one of the most regulated in the world with a zillion tests, there is no mandatory test for effects on electronics from near field coupling of transmitters such as mobile phones. I had a product many years ago that passed all the regulatory tests, but would fail when put right up to a mobile phone. Adding a 47pF cap to the clk line an external EEPROM solved the problem.
I can definitely recommend Yokogawa DL series. All of them in fact. Awesome user interface. Deep memories. Super fast updating of the screen makes them feel very analog. Stay away from any DSO under $5k. They are usually crippled by either short memories, lo res displays, or pathetic real time updating. I recommend you have at least 500k deep memory, >15 screen updates per second and VGA or better resolution.
I think it barely had the best intentions. I hear that inclusion of lead was because of ONE scientific study that hinted alloys of lead MAY leach into ground water and that paper has since been withdrawn. For those of you not in the industry, solder used to be 60/40 tin/lead. It melted at 188oC and was processed at 225oC for reflow (Suface mount oven) and 245oC for wave soldering (through hole parts). Thanks to the EU, lead was banned so we had to move to things like SAC305 (96.5% tin/3% silver/0.5% copper). SAC and similar alloys melt at around 220oC and thus need significantly hotter process temperatures. This tended to strip wavesolder machine iron based solder baths, and require more zones in reflow ovens. So there goes a few billion replacing machines. Hi tin solders also have more brittle solder joints (likely the cause of Nvidias problems) because pure tin in less ductile and forms different intermetallics. Hi tin solder can also tin whisker causing short circuits to adjacent pins. It also created logistics nightmares because you now had storerooms with ROHS compliant & non compliant parts that look identical. Technicians when reworking now have to use lead or lead free solder depending on what they rework (and the solder looks identical except the lead free solder is much harder to use) So in summary:- ROHS banning of lead - Based on one dubious scientific paper about possible lead leaching into groundwater - Cost billions for the industry to implement - Increases energy use becuase of hotter process temperatures - Copper in solder baths can strip solder out of OSP based PCB's - Makes it harder to make stuff and rework stuff because of narrow process windows (more waste from rejects) - Makes solder joints more brittle. (big problem for micro BGA parts used on mobile phones and high end chips like FPGAs & graphics) - Can grow tin whiskers, and the industry is only just beginning to understand why
George Bush wet dream. Mandatory encoding of the cars VIN & speed into modulation of the cars parking led lights. Makes that big brother tracking just one step easier.
The Patent system is just showing the same signs as Americas current version of capitalism. ie.. huge greed and poor government oversight that eventually leads to the destruction of the whole system.
Most/. USA readers probably don't realise that Mythbusters was conceived and is produced by an Australian company Beyond Productions, who among many other shows used to produce a geek show Beyond 2000, (which was spun out of an ABC program towards 2000) Don't expect Mythbusters to tackle anything controversial. They claim on their website to wipe anything from their message board to do with 9-11. A shame because there are a few things I'd love them to test like - Making multi minute phone calls from 30k ft with 2001 phone tech and no onboard plane phones (I already know its not possible, but would love to see them try) - Getting a 767 sim and attempt to fly the same path as pentagon plane (Including being in ground effect for 1km before hitting the building), but only having light plane real world experience. (Note NTSB has a video of the flight data recorder (which strangely has a different approach path to the physical evidence.. maybe they could try both))
I actually develop near field magnetic field radiators. Two of the main issues are - Near field magnetic decay 1/r^3 (ie very quickly) - There are very strict emissions standards for near field mag radiators. Most of the world obeys ETSI EN 300-330 which give sensible measurements units in dBuA/m^2. The US has its own crazy FCC rule in dBuV/m2 (go figure) So one would need to change legislation to enable decent powers to be coupled over any appreciable distance (ie over a metre)
This is one place where vista works well, in the home. (At work we have NO vista machines) In the year we have used Vista MCE, the all important WAF has been very high, and the system overall very stable and responsive, only requiring an accasional USB tuner reboot. I considered Myth, but mountain looked steep, and my time available for home brew about nil. The install was almost painless,and in OZ (where the is no TiVO culture) we get free guides thanks to volunteers.
How on earth does anyone survive on that! Australia has a similar cost of living, and our minimum wage is around US$15/hour. Is the USA that broke, or do you have a much cheaper cost of living.
I agree tants days are numbered, although they are trying to make a comeback in Niobium oxide. The last time I used a tantalum (many years ago), was for a nat semi voltage regulator output that had a specific ESR requirement. That said, they work OK if you de rate them and never ever allow them directly on the input of a power supply (esp battery), as the di/dt will kill them.
All the more reason to say that if you don't produce commercial product (which includes reasonable intents on volume and price considering your company size) within 5 years, you loose exclusive rights, or other companies may use the patent with a small mandated royalty.
Yes but the article states it is self current limiting "they lose their superconducting abilities and become normally resistive, damping the current. " So how do they stop the cables from literally exploding if they loose their superconductivity. Unless they become essentially an insulator, it would be like trying to power a whole suburb through household extension cord. (ie the cord would vaporise)
ROHS has been a billion dollar expense to the electronics industry, and it is argued the solutions are causing more enviromental damage than the original problem which was based ONE scientific paper out of the USA which was since retracted. Lead free is a huge pain. All soldering processes run 20deg hotter, consuming more electricity and stressing components, especially MLS devices (Mousture absorbed by components turns to steam fracturing parts if you are not careful). Wetting is poorer. Tin whiskers is a problem the industry is still trying to fully understand. All because some beurorats in the EU listened to one faulty research paper. http://www.edn.com/article/CA6355639.html
ROHS compliance has cost the electronics industry Billions to implement, was based on one now retracted faulty scientific study about leaching of lead from electronics into ground water. This costs the world continuing $$$ from higher process temperatures, more brittle solder connections, tin whiskers. Thanks EU!
But you are so wrong, because my taxes (at least in Oz) have to pay for your medical bills when you get cancer... and no the taxes don't cover the total cost to society of your disrespect for your own life.
I recently heard an insightful comment about the USA on Radio National (ABC Australia) The USA was founded on the principal of 'freedom for the individual'. This shows with the USA's weak social welfare systems, and business culture of domination at all cost. On the other hand in Europe, and to less extent the commonwealth countries, the attitude is more focused on a collective balance of both the individual and the community. I have found this especially so in negotiations with European companies. They genuinely want you to succeed as they know thats good for them and the common good. Perhaps this deep American culture of the individual is the core Micosofts (ie Gates & Ballmer) selfish and destructive behaviour.
Well, I think I was just a wee teenager when blake 7 was on, and remember having the cr$# scared out of me by the bubbling skin effect when they went to warp speed... I'm sure though today it would all look pedestrian amongst 30 years of sfx progress.
Thanks BadAnalogyGuy for pointing out the more substantial reason for barley price change.
Am I the only one sick of hearing about climate change causing everything. I've lost count of the stories where 'climate change is causing x devestation', when in fact in the content of the story it has nothing to do with it. Climate change due to man made influence is NOT YET FACT. It is still a theory with not enough data, but with quasi religious zealots who wish to have you think otherwise.
I've seen a lot of very uninformed comments on 'high gain antennas' MiFare is a 13.56MHz system (ISM band), that uses H-Field coupling (ie near field magnetic coupling) in a loose transformer coupled arrangement. The near field attenuates at 1/r^3, and as a rough guide you can read this type of tag to about 1.5 x loop diameter.
At 13.56Mhz, you can only make the antenna so large before the inductance of the antenna makes it impossible to resonate. We in fact have a complex stub tuned antenna of about 1m diam, and that was difficult.
Another problem, is you have to start pumping out so much power, it becomes extremely difficult to see modulation on the carrier above the TX noise.
Now that said, it sounds like NXP (who have one of the worst web sites on the net), are in deep doodoo. The reason is that MIFARE has huge rollouts in transportation systems, especially in asia, and these cards contain real monetary value. System integrators, are now going to have to put extra work into either live back to central database checking (which will be hard on mobile platforms like busses), or upgrade systems to the triple des encrypted (and more expensive) cards.
OK, I'll bite. (sorry karma) First we are no longer allowed to label them handicap.. it's accessible parking. Second, parking is very valuable space nowadays. Third, in the seven years we were at one business site, our 'accessible parking' was not used once.
So while I agree they should be available where the general public visits (like shops), for business to business sites, I think think they should only be available where there are lots of carparks ( >40)
If you are presented with a contract by a company, you can cross out sections of the contract that you can't live with. Which is exactly what we did on a construction contract recently. The engineering firm attempted to contract away all of their liability with the design of a 500ton slab. We crossed out those sections of the contract, they agreed, and the job went ahead.
This is not practical for most boxed software, so I think the government should legislate common law rights in regards to purchased commercial software. This could only be then extended or altered by a signed contract between the parties.
Slashdot Mirror
So the poster is correct. It is a 217Hz RF pulse with about 500uS pulse width.
Cell phones use an electric field antenna which produces a high near field electric field that decays at 1/r cubed, and a propagating electromagnetic field that decays at 1/r.
It is most likely the near field electric field (capacitively coupled) that is consequently demodulated by any non linear components in your speaker amplifiers as the PA (Power Amplifier) in the phone changes power level.
Even though the electronics industry is one of the most regulated in the world with a zillion tests, there is no mandatory test for effects on electronics from near field coupling of transmitters such as mobile phones.
I had a product many years ago that passed all the regulatory tests, but would fail when put right up to a mobile phone. Adding a 47pF cap to the clk line an external EEPROM solved the problem.
I can definitely recommend Yokogawa DL series. All of them in fact. Awesome user interface. Deep memories. Super fast updating of the screen makes them feel very analog.
Stay away from any DSO under $5k. They are usually crippled by either short memories, lo res displays, or pathetic real time updating.
I recommend you have at least 500k deep memory, >15 screen updates per second and VGA or better resolution.
I think it barely had the best intentions.
I hear that inclusion of lead was because of ONE scientific study that hinted alloys of lead MAY leach into ground water and that paper has since been withdrawn.
For those of you not in the industry, solder used to be 60/40 tin/lead. It melted at 188oC and was processed at 225oC for reflow (Suface mount oven) and 245oC for wave soldering (through hole parts).
Thanks to the EU, lead was banned so we had to move to things like SAC305 (96.5% tin/3% silver/0.5% copper). SAC and similar alloys melt at around 220oC and thus need significantly hotter process temperatures. This tended to strip wavesolder machine iron based solder baths, and require more zones in reflow ovens. So there goes a few billion replacing machines.
Hi tin solders also have more brittle solder joints (likely the cause of Nvidias problems) because pure tin in less ductile and forms different intermetallics. Hi tin solder can also tin whisker causing short circuits to adjacent pins.
It also created logistics nightmares because you now had storerooms with ROHS compliant & non compliant parts that look identical. Technicians when reworking now have to use lead or lead free solder depending on what they rework (and the solder looks identical except the lead free solder is much harder to use)
So in summary:-
ROHS banning of lead
- Based on one dubious scientific paper about possible lead leaching into groundwater
- Cost billions for the industry to implement
- Increases energy use becuase of hotter process temperatures
- Copper in solder baths can strip solder out of OSP based PCB's
- Makes it harder to make stuff and rework stuff because of narrow process windows (more waste from rejects)
- Makes solder joints more brittle. (big problem for micro BGA parts used on mobile phones and high end chips like FPGAs & graphics)
- Can grow tin whiskers, and the industry is only just beginning to understand why
Great move EU!
George Bush wet dream.
Mandatory encoding of the cars VIN & speed into modulation of the cars parking led lights.
Makes that big brother tracking just one step easier.
The Patent system is just showing the same signs as Americas current version of capitalism.
ie.. huge greed and poor government oversight that eventually leads to the destruction of the whole system.
As the US Financial system unwinds into a 1929 horror show, you will suddenly find out how all these loss of freedoms will really be used.
Most /. USA readers probably don't realise that Mythbusters was conceived and is produced by an Australian company Beyond Productions, who among many other shows used to produce a geek show Beyond 2000, (which was spun out of an ABC program towards 2000)
Don't expect Mythbusters to tackle anything controversial. They claim on their website to wipe anything from their message board to do with 9-11. A shame because there are a few things I'd love them to test like
- Making multi minute phone calls from 30k ft with 2001 phone tech and no onboard plane phones (I already know its not possible, but would love to see them try)
- Getting a 767 sim and attempt to fly the same path as pentagon plane (Including being in ground effect for 1km before hitting the building), but only having light plane real world experience. (Note NTSB has a video of the flight data recorder (which strangely has a different approach path to the physical evidence.. maybe they could try both))
But don't hold your breath.
I actually develop near field magnetic field radiators.
Two of the main issues are
- Near field magnetic decay 1/r^3 (ie very quickly)
- There are very strict emissions standards for near field mag radiators. Most of the world obeys ETSI EN 300-330 which give sensible measurements units in dBuA/m^2. The US has its own crazy FCC rule in dBuV/m2 (go figure)
So one would need to change legislation to enable decent powers to be coupled over any appreciable distance (ie over a metre)
This is one place where vista works well, in the home. (At work we have NO vista machines)
In the year we have used Vista MCE, the all important WAF has been very high, and the system overall very stable and responsive, only requiring an accasional USB tuner reboot.
I considered Myth, but mountain looked steep, and my time available for home brew about nil.
The install was almost painless,and in OZ (where the is no TiVO culture) we get free guides thanks to volunteers.
How on earth does anyone survive on that!
Australia has a similar cost of living, and our minimum wage is around US$15/hour.
Is the USA that broke, or do you have a much cheaper cost of living.
According to the BigMac index, fast food cost is similar.
http://www.economist.com/finance/displaystory.cfm?story_id=11793125
What gives?
I agree tants days are numbered, although they are trying to make a comeback in Niobium oxide. The last time I used a tantalum (many years ago), was for a nat semi voltage regulator output that had a specific ESR requirement.
That said, they work OK if you de rate them and never ever allow them directly on the input of a power supply (esp battery), as the di/dt will kill them.
All the more reason to say that if you don't produce commercial product (which includes reasonable intents on volume and price considering your company size) within 5 years, you loose exclusive rights, or other companies may use the patent with a small mandated royalty.
Yes but the article states it is self current limiting
"they lose their superconducting abilities and become normally resistive, damping the current. "
So how do they stop the cables from literally exploding if they loose their superconductivity.
Unless they become essentially an insulator, it would be like trying to power a whole suburb through household extension cord. (ie the cord would vaporise)
In almost 20 years of engineering, I have not met one Female engineer that does design work. (Only sales)
ROHS has been a billion dollar expense to the electronics industry, and it is argued the solutions are causing more enviromental damage than the original problem which was based ONE scientific paper out of the USA which was since retracted.
Lead free is a huge pain.
All soldering processes run 20deg hotter, consuming more electricity and stressing components, especially MLS devices (Mousture absorbed by components turns to steam fracturing parts if you are not careful). Wetting is poorer. Tin whiskers is a problem the industry is still trying to fully understand.
All because some beurorats in the EU listened to one faulty research paper.
http://www.edn.com/article/CA6355639.html
ROHS compliance has cost the electronics industry Billions to implement, was based on one now retracted faulty scientific study about leaching of lead from electronics into ground water.
This costs the world continuing $$$ from higher process temperatures, more brittle solder connections, tin whiskers. Thanks EU!
But you are so wrong, because my taxes (at least in Oz) have to pay for your medical bills when you get cancer... and no the taxes don't cover the total cost to society of your disrespect for your own life.
I recently heard an insightful comment about the USA on Radio National (ABC Australia)
The USA was founded on the principal of 'freedom for the individual'. This shows with the USA's weak social welfare systems, and business culture of domination at all cost.
On the other hand in Europe, and to less extent the commonwealth countries, the attitude is more focused on a collective balance of both the individual and the community.
I have found this especially so in negotiations with European companies. They genuinely want you to succeed as they know thats good for them and the common good.
Perhaps this deep American culture of the individual is the core Micosofts (ie Gates & Ballmer) selfish and destructive behaviour.
Often the person who sees the problem *IS* the person to champion that cause.
Well, I think I was just a wee teenager when blake 7 was on, and remember having the cr$# scared out of me by the bubbling skin effect when they went to warp speed... I'm sure though today it would all look pedestrian amongst 30 years of sfx progress.
Thanks BadAnalogyGuy for pointing out the more substantial reason for barley price change.
Am I the only one sick of hearing about climate change causing everything. I've lost count of the stories where 'climate change is causing x devestation', when in fact in the content of the story it has nothing to do with it.
Climate change due to man made influence is NOT YET FACT. It is still a theory with not enough data, but with quasi religious zealots who wish to have you think otherwise.
I've seen a lot of very uninformed comments on 'high gain antennas'
MiFare is a 13.56MHz system (ISM band), that uses H-Field coupling (ie near field magnetic coupling) in a loose transformer coupled arrangement.
The near field attenuates at 1/r^3, and as a rough guide you can read this type of tag to about 1.5 x loop diameter.
At 13.56Mhz, you can only make the antenna so large before the inductance of the antenna makes it impossible to resonate.
We in fact have a complex stub tuned antenna of about 1m diam, and that was difficult.
Another problem, is you have to start pumping out so much power, it becomes extremely difficult to see modulation on the carrier above the TX noise.
Now that said, it sounds like NXP (who have one of the worst web sites on the net), are in deep doodoo.
The reason is that MIFARE has huge rollouts in transportation systems, especially in asia, and these cards contain real monetary value.
System integrators, are now going to have to put extra work into either live back to central database checking (which will be hard on mobile platforms like busses), or upgrade systems to the triple des encrypted (and more expensive) cards.
OK, I'll bite. (sorry karma)
First we are no longer allowed to label them handicap.. it's accessible parking.
Second, parking is very valuable space nowadays.
Third, in the seven years we were at one business site, our 'accessible parking' was not used once.
So while I agree they should be available where the general public visits (like shops), for business to business sites, I think think they should only be available where there are lots of carparks ( >40)
This is not practical for most boxed software, so I think the government should legislate common law rights in regards to purchased commercial software. This could only be then extended or altered by a signed contract between the parties.