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Author Topic: EMP Government study about its effects on systems  (Read 12454 times)
ALCO141
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« on: June 30, 2009, 04:04:00 AM »

the most in depth study about emp effects i have seen including tests on cars, radios, and a lot of other items. interestingly they mention ham radio as one of the ways that the nation may overcome the communication failure.

fyi:

http://www.empcommission.org/reports.php
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N0UJR
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« Reply #1 on: July 01, 2009, 08:37:34 AM »

Thank You.  This is an excellent document every ham should read!  If we are going to be able to help in the aftermath of an EMP attack, we need to protect our equipment, but we have to do it before the EMP event happens!
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K9KJM
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« Reply #2 on: July 01, 2009, 09:41:22 PM »

Yes, Thanks for the link.  Lots of good info.

Most hams need to understand that an EMP event DOES have a very high chance of shutting down commercial AC power over very widespread areas. (Be prepared to operate on your battery/solar etc supply)

However, As long as the typical ham station is well protected for lightning strikes, They have a very good chance of survival from EMP also. (EMP is like a lightning strike, But with faster rise time)  

Distance matters.  IF you are more than a few hundred miles from the event, The need for special protection with stuff like a Faraday cage, etc should not really be needed. IF you are close enough that you DO need such protection, I suspect you may have bigger problems than just the EMP damage..........
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K2GW
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« Reply #3 on: July 02, 2009, 07:05:21 AM »

One other thing you can do is to always have one spare transceiver totally disconnected from everything (power supply cables, antenna, computer control lines, microphone, etc) that is capable of operating off of a automobile battery.  This good practice for lots of contingencies including EMP.

For home use, that could be the radio in your Go Kit.  For EOC and Red Cross Chapters, a spare transceiver could be so designated. This could be an older radio that has been replaced in daily use with a newer model.

Just storing without connecting wires that might act as "antennas" should be sufficient.  But if you want to be really sure, store the transceiver in a large metal tin, such as those that holiday pop corn is sold in.

A spare coax and portable antenna should be also stored in case the regular ones also get damaged.

One hint about spares of any type is that they should be tested regularly.  

73

Gary, K2GW
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K4YRK
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« Reply #4 on: July 15, 2009, 09:32:22 AM »

This study highlights a new threat to our nation that is an inviting possibility to terrorist groups or rogue nations.  
I wrote an article for e-Ham about this in early June that you can find in the article list and it brought dozens of comments by other hams.

A new 'best selling novel called "One Second After" takes on this topic with a fictional story of the results on a western NC town and the southeast region of our country after such an attack.  It is scary.

We as hams, do have capability to help our country after such an attack with critical communications, but we ourselfs must protect our own personal and familty survival and the survival of our ability to communicate.

73
K4YRK
Dave Garner
www.vhfhamradio.com
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KE4DRN
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« Reply #5 on: July 15, 2009, 05:26:19 PM »

Hi

http://www.eham.net/articles/21592

73 james
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N0UJR
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« Reply #6 on: October 19, 2009, 08:15:08 PM »

Dave

I really enjoyed the article you wrote on EMP.  I have been working to raise some red flags on the subject of EMP preparedness for the amateur radio community. I'm writing articles and giving a presentation to the local ham club on the subject.

Would like to hear from you.  Please email me at tech1906@yahoo.com  

Greg
N0UJR
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K2GW
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« Reply #7 on: October 29, 2009, 03:06:46 PM »

See also the excellent article on EMP in the November 2009 issue of QST by N2HX, a personal friend of mine and someone who's actually designed and installed EMP protected radio rooms in our state EOC.

73

Gary, K2GW
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N8QH
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« Reply #8 on: December 24, 2009, 10:51:09 AM »

I suggest a careful reading on the available research material. The Russians claim to have the ability to generate a 200,000 volt per meter pulse. If such an event occurred 500 km over Nebraska, the field strength would only be diminished by 50% in California and New York. A "few hundred miles distance" wouldn't produce any significant reduction in the pulse intensity. Only a few percent at best. Interestingly though, there is a "null area" almost directly beneath the point of detonation (maybe good news for the folks in Omaha - who seem to always get nuked first in  WW III movies).

One of the most important conceptual points is that we are NOT talking about an RF field. Instead, an EMP is a massive shock front of electrons produced by the Compton Effect. It's a better model to picture a more mechanical effect like the movement of billiard balls, or as the author on One Second After phrased it: an avalanche triggered by a pebble. Except that the 1 megaton "pebble" has a power output of 17x10^15 watts, or: 17,000,000,000,000,000 watts (17 peta watts) -- nearly all of which is converted into a single pulse of electrons when X ray and gamma waves strike the upper atmosphere (due to the Compton Effect).

Attenuation with distance is minimal because of the vacuum of space. Nearly as much energy strikes the upper atmosphere 1,000 miles away as directly beneath the detonation point (diminished mostly by the decreasing angle of incidence with the atmosphere and "square law" attenuation).

I worked on EMP hardening as a broadcast engineer during the height of its awareness - the 70s and 80s. We lovingly kept our old studio and transmitter working - both of which were devoid of even a single semiconductor. We impressed the state Civil Defense folks enough to get a free diesel generator (itself devoid of any semiconductors). And ALL of the literature back then warned to NOT consider lightning protection to be adequate. The rise time of the model lightning strike is an 8 microsecond rise followed by a 20 microsecond trailing edge (at the 50% intensity points). An EMP has a rise time of about 20 nanoseconds - nearly 1,000 times faster. Too fast for gas discharge lightning arrestors to develop a plasma, too fast for spark gaps, and too fast for fuses to blow. All of these devices are good to have though to protect against the secondary waves -- which ARE radio frequency waves. Little has been said about the secondary emissions that would be the consequence of every conductive object being shock excited into resonance - just like shock exciting a tank circuit. Most of the tests the military does involve placing the object under test beneath an arch, and then zapping the object with a single pulse. In the real world, there will be enormous secondary waves generated when everything conductive rings like a bell after being shock excited by the EMP. The entire radio frequency spectrum would then be affected by the "S" waves thus produced.

Many people in the RF field have a greatly diminished sense of proportion about the sheer intensity of an EMP. If you have ever seen a nuclear bomb explode in slow motion, you will recall that at the very beginning there is just a pinpoint of light. That is the bomb itself exploding, and it releases only a tiny proportion of its energy in visible light. Next, there is the enormously more powerful fireball. Most of the energy released by a nuke is in the form of X rays and gamma rays. When one is detonated in the atmosphere, the atmosphere absorbs that radiation and re-radiates it as heat. So imagine all the power in that fireball passing unhindered in the vacuum of space... until it strikes the atmosphere. Most of that energy is then converted into a single high intensity pulse of electrical energy.

The proportion to ordinary experience is difficult to conceive of. Imagine you had a 2 megawatt transmitter a few miles away. Assume the field strength is 500 millivolts per meter where you are. An EMP releases 8 TRILLION TIMES as much power as that 2 megawatt transmitter, and if it were detonated 500 km above Nebraska, the distance from the "source" to where you are is only about 26 miles - coast to coast - anywhere in the continental U.S. We are talking about something intense enough to produce arc paths in a roll of spooled RG8 coax cable, making it unusable. The official literature suggests coax be laid out in a straight line if an EMP is anticipated (as if we'd get any warning).

Would any nation contemplate doing such a thing? In March 2005 Russian Captain, First Rank, H. Rezyapov wrote an article in a Russian Defense Ministry publication entitled, “Asymmetric Threats to the National Security of the United States.” He concluded that it was possible to defeat the United States by asymmetric attack, including a nuclear EMP attack Implicit in this analysis was the view that it was possible to launch nuclear EMP attacks against the United States without nuclear retaliation. Captain Rezyapov wrote:

"Such a blast would simultaneously take out of action almost all of the satellites orbiting above the United States. It is thought that a nuclear blast over the territory of the state of Nebraska at an altitude of 300 km would be able to affect up to 90% of the territory of the United States by the action of its EMP."

If such an attack were to happen... welcome to a world without transistor-based electronics. Please set your watches back 100 years (assuming they are mechanical watches that still work).

There are countermeasures that would be of some value. Wrapping your radios in conductive foil and then shielding them from magnetic fields might save them. I personally like steel ammo cases because they're cheap on the surplus market. Nearly every home has a box designed to block microwave energy - toss your VHF/UHF gear in the microwave oven (after unplugging it). Or you can do like many yachtsmen do when they traverse a thunderstorm at sea - toss your delicate gear in the conventional oven. Many EOCs keep their gear in steel storage containers, which unbeknown to them are rather effective at blocking an EMP.

But if you want really hardened gear that will survive a second wave attack while you are using it, hang on to your vacuum tube radios. If an EMP attack occurs, vacuum tube gear that is capable of being battery operated (how many people remember multivibrators?) will be worth its weight in gold. Or many cans of beans and stew, which would be even more valuable than gold.

In an intelligence coup for the west, on September 6th, 1976, a MiG 25 Foxbat of the Soviet Air Defense Command flown by Lt. Viktor Belenko landed at Hakodate airport, Japan. Belenko was defecting to the west and gave them the first in-depth look at the aircraft. It was carefully dismantled and analysed by the Foreign Technology Division of the USAF, at Dayton, Ohio. Our military was highly amused when they discovered that all the avionics on board were based on vacuum tubes. They were surprised to find the Soviets design was so "primitive" -- that is, until they realized the vacuum tube technology was inherently immune to EMP. From what country do most of our vacuum tubes come today?

Finally, if you think our military must have taken the precaution of providing EMP hardening: most of the military electronics manufactured recently have been made under waivers releasing the manufacturers from complying with EMP hardening standards.
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N8QH
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« Reply #9 on: December 26, 2009, 03:29:16 PM »

Quoting from above:

"However, As long as the typical ham station is well protected for lightning strikes, They have a very good chance of survival from EMP also. (EMP is like a lightning strike, But with faster rise time)"

Most of the RF energy emitted from lightning strikes is in the rage of a few hundred hertz to 10 kHz. All of the available research states that conventional lightening protection is inadequate, due to the much more rapid rise time of an EMP pulse. One exception is metal oxide varistors (MOVs), which can respond within a few nanoseconds. Devices that depend on the creation of a plasma: gas discharge arrestors and spark gaps, will allow an EMP pulse to pass right through unimpeded because of their much slower response times. By the time a plasma forms, the EMP has already come and gone. At best, conventional lightning protection would provide only minimal EMP protection.

Lightning is very rare in some parts of the country, and consequently very little lightning protection is deployed in those regions. (See http://www.lightningsafety.noaa.gov/lightning_map.htm). Here in Northern California, I could go an entire lifetime without seeing just one of the thunderstorms that were a weekly summer occurrence while I lived in Houston.

MOVs are useful for diminishing an EMP transient on AC power lines, but are impractical on RF-carrying circuits due to their intentionally inherent parallel capacitance. Designed to be placed in parallel with the protected circuits, MOVs would simply shunt the RF. AC transients of the intensity anticipated from an EMP will probably cause the MOVs to fail after doing their duty, and they often fail in a dead-short condition, or become partially conductive at nominal operating voltages and overheat after absorbing a substantial transient. They would have to be removed before the equipment could be re-energized, and replaced if any subsequent protection was required. There's nothing to stop an adversary form hitting us more than once, and in fact, that would be an effective strategy.
 
Quoting from above:

"Distance matters. IF you are more than a few hundred miles from the event, The need for special protection with stuff like a Faraday cage, etc should not really be needed. IF you are close enough that you DO need such protection, I suspect you may have bigger problems than just the EMP damage.........."

While distance is always a mitigator, it doesn't offer significant protection. The EMP is generated at the atmospheric interface with space, and any point on the surface that is within the line-of-sight horizon of the detonation will receive a significant pulse. The published models show California and New york receiving 50% of the intensity from a single detonation over Nebraska. If three devices were distributed west-to-east over the US, there would be no significant difference in intensity anywhere in the contiguous states. Under that condition, considering distance as a protection factor would be a bit like arguing that it is safer to jump out a window on the 80th story of a building - than on the 81st story. The consequences are the same in both cases.

The health risk to anyone directly beneath the detonation would be minimal. Viewed from that location and looking straight up, the detonation would appear only as a very bright and brief point of light. Nearly all of the energy that is dissipated in an atmospheric detonation as heat, shock and blast; would instead be dissipated in the EMP. While a person at that location would receive some gamma radiation, the combination of the very short duration and atmospheric absorption would limit that dose to a very small amount, producing no negative health effects, and there would be no fallout.

Even in the case of an atmospheric detonation, anyone close enough to receive a significant amount of radiation from the initial explosion - would be killed milliseconds later by the fireball and blast - neither of which occur in a detonation taking place outside the atmosphere.

The Executive Report from the EMP Commission states that: "EMP is not reported in the scientific literature to have direct effects on people in the parameter range of present interest." (http://www.empcommission.org/docs/empc_exec_rpt.pdf, page 4).

The old argument that rationalized inaction in the past that: "we would all be dead anyway, and the enemy would get nothing," isn't true in the case of an EMP attack. An EMP attack would be the ultimate strategy to cripple the nation while not destroying its natural and agricultural resources -- leaving "the spoils of war" undamaged.

Such an attack didn't occur before because we weren't so dependent on vulnerable technology. 20 years ago, no one had heard of the Internet. My own job is that of a Certified Information Systems Security Professional. It is a daily occurrence for me to consider the consequences of disruptions and denials of service to this delicate technology. So far as the Internet is concerned, if an EMP attack occurred today, all of that technology would cease to function - permanently. None of it is shielded against such an attack, and only a few systems linked by fiberoptics would survive.
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K9KJM
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« Reply #10 on: December 26, 2009, 11:44:49 PM »

"Depends on what your defination of "is" is......"  As they say

Yes, Very potent EMP devices ARE out there. I maintain that the odds of the use of one like that described over the U.S. Remain really quite slim.

Whereas the odds of some type of terrorist group detonating a plain nuclear device (Like the so-called (And missing) Former Soviet "suitcase" nukes)(Or a number of them) Either at ground level, Or at most a mile or so above ground, As in a small plane) Is MUCH higher, And in fact many folks consider it only a matter of time until that happens.

And for those type EMP events, I maintain that decent lightning protection and distance from the event will be sufficient.
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N8QH
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« Reply #11 on: January 09, 2010, 01:19:31 PM »

If the threat model is a terrorist group, I completely agree: an EMP attack is not a likely scenario.

When performing threat modeling in my field, we often refer to the MORE Model: Motivation, Objective,  Resources, and Experience. The current crop of terrorists (Al Queda, et al) are motivated by a fundamental hatred of our culture - not by the traditional motivations of nation-state conflict: prestige, domination, and material gain. Their objective is to kill as many people as possible in as horrific a manner as possible in order to damage what they perceive to be our greatest cultural weapon: our economy, which is highly dependent on the optimistic belief in continuous growth. And part of the psychological effectiveness of their attacks has been their technical simplicity - it's not hard to learn how to steer an airplane into a building - which fosters the impression that there could be a potential terrorist hiding in every shadow. That simplicity also diminishes the likelihood of detection. The resource challenges for carrying out an EMP attack are severe, and I agree make an EMP attack by a terrorist organization very unlikely. But beyond the challenge of obtaining fissile materials, constructing a crude device with low yield would not have been beyond the abilities of the 9-11 terrorists - some of whom were degreed engineers. Constructing a radiation dispersal device ("dirty bomb") would be even simpler. The psychological impact and the resulting impact on our economy from the perception that Al Queda has "gone nuclear" would be so extreme that they're hard to imagine.

It's my own belief that the treat from an EMP attack is currently limited to the resources of a nation-state, although that doesn't rule out the possibility of a nation-state using a terrorist organization as a proxy. The motivation for nation-state to carry out such an attack is quite high: they may believe that they can capture all of our natural resources undamaged, while thwarting a retaliatory strike by concealing the origin of the attack - the forensic evidence would evaporate along with the computers that contained it.

I believe you are correct in presuming that lightning protection would be beneficial in protecting equipment from the "E2" pulse. And the Commission report agrees with that presumption. But as for the initial E1 pulse, the Commission concluded (referring specially to aircraft systems): "The frequency composition of lightning and EMP differ enough so that lightning protection does not ensure EMP protection." That conclusion is consistent with all of the research I have seen in the past 40 years of my own interest in the topic. There are few lightning protection systems that are capable of shunting a 1 nanosecond rise-time pulse.

The Commission reported that: "The early time EMP, or E1, is a freely propagating field with a rise time in the range of less than one to a few nanoseconds. E1 damages or disrupts electronics such as the SCADA, DCS, and PLC as well as communications and to some extent transportation (necessary for supplies and personnel). This disrupts control systems, sensors, communication systems, protective systems, generator systems, fuel systems, environmental mitigation systems and their related computers, as well as the ability to repair. SCADA components, in particular, are frequently situated in remote environments and operate without proximate human intervention. While their critical electronic elements are usually contained within some sort of metallic box, the enclosures’ service as a protective Faraday cage is inadequate. Such metallic containers are designed only to provide protection from the weather and a modicum of physical security. They are not designed to protect the electronics from high-energy electromagnetic pulses, which may infiltrate either from the free field or from the many antennae (cable connections) that compromise electromagnetic integrity." [EMP commission report, page 34]

The Commission did test the radios and computer systems used by public safety agencies. The radios held up fairly well to fields as high as 50 kV/m. The weak link was the computer systems: "Results indicate that some computer failures can be expected at relatively low EMP field levels of 3 to 6 kilovolts per meter (kV/m)." "[However]... most of the fixed installation public safety radio systems include telecommunication links between the computer-aided dispatch terminals and the main or repeater radio units. Therefore, because of computer failures in dispatch equipment, communication system failures might occur at EMP field levels as low as 3 to 6 kV/m [report page 153]." I believe it's fair to assume that any general purpose unhardened computer that is connected to anything at the moment of an EMP exposure of even low intensity will be probably toast. I'm pessimistic about how well modern Ham gear will hold up, considering much of its technology is identical to that found in general purpose computers.

So far as distance being a protective factor is concerned, I refer the reader to the map on page 6 of the Executive Report. It shows the E1 field strength from an EMP detonation near Chicago falling to 50% intensity only after it was out over the Atlantic beyond Washington, D.C. and New York. Three detonations of that type would cover the entire 48 States with at least a 50% field intensity E1 pulse.
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N8QH
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« Reply #12 on: January 10, 2010, 12:56:04 PM »

A very interesting historical video documentary on EMP and EMP testing by the US military, codenamed TRESTLE and located at the Kirtland Air Force Base, can be viewed at:

http://www.ece.unm.edu/summa/notes/trestle_movie.html
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N8QH
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« Reply #13 on: February 09, 2010, 11:52:30 AM »

On the topic of the likelihood of an EMP attack, please see the article at:

http://www.wnd.com/news/article.asp?ARTICLE_ID=43956

Quoting an excerpt from the above:

"Iran is not only covertly developing nuclear weapons, it is already testing ballistic missiles specifically designed to destroy America's technical infrastructure, effectively neutralizing the world's lone superpower, say U.S. intelligence sources, top scientists and western missile industry experts.

The radical Shiite regime has conducted successful tests to determine if its Shahab-3 ballistic missiles, capable of carrying a nuclear warhead, can be detonated by a remote-control device while still in high-altitude flight.

Scientists, including President Reagan's top science adviser, William R. Graham, say there is no other explanation for such tests than preparation for the deployment of electromagnetic pulse weapons – even one of which could knock out America's critical electrical and technological infrastructure, effectively sending the continental U.S. back to the 19th century with a recovery time of months or years."
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ONAIR
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« Reply #14 on: February 10, 2010, 02:12:52 PM »

May be a good idea to keep an old tube transceiver and generator around, just in case!
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