A little clarification on the EMP topic

This is education talking, I am not going to quote references, especially since finding this info might not be easy. If you have any questions try using Google. When an EMP weapon is specifically designed for the purpose of destroying electronics, it does not hit the same EMP frequency a nuclear weapon does. As I have stated many times on this web site, contrary to popular myth modern circuits are not easily destroyed by nuclear EMP. This is because they are designed entirely differently than circuits were designed in the 1970's when the EMP myth took hold, and even in the 70's nuclear EMP as presented was a load of baloney.

Modern EMP weapons do not rely on a nuclear detonation to generate an EMP pulse

Modern EMP weapons function by generating an enormous magnetic field, and then using explosives to destroy whatever is creating that magnetic field. Since magnetic fields actually take on a physical form that is tangible and real, destroying the source of the magnetic field while that magnetic field is fully developed forces the magnetic field to extend outward very rapidly because it exists in a physical form and suddenly has nothing to contain it. For example -

If you take a neodymium magnet and destroy it with a hammer it will create a small EMP because the magnetic field it had will suddenly have nowhere to exist. The magnetic field will therefore rapidly extend outward, and induce electrical currents into any conductors that are nearby. And a step farther - If a superconducting ring magnet which has had an enormous electric current induced into it (which will continuously flow in a circle around the magnet) is suddenly destroyed by an explosive, the total electrical energy potential that is flowing through the magnet will have no place to exist, and will rapidly expand outward in the form of magnetic waves and produce an enormous EMP. Since superconducting magnets are still difficult to do and impractical to build into a weapon, EMP weapons do not use superconducting magnets.
Modern EMP weapons use coils of wire wrapped around an explosive core. A large electric current is passed through the wire, and when the resulting magnetic field is at it's peak, the explosives destroy the wire coils. And the EMP signature from such a device is drastically different from what is produced by a nuclear weapon
Nuclear EMP is not created by destroying an existing magnetic field. Nuclear EMP is created when the atoms in the device and surrounding the device get compressed by the shock wave created by the massive and instantaneous detonation. Nuclear EMP characteristics are therefore greatly affected by where the nuke goes off, a nuclear weapon of the exact same design will produce an EMP of one type when detonated in air, and have entirely different EMP characteristics when detonated below ground or in water. So nuclear EMP is very unpredictable, even humidity will affect its characteristics and since it is created by a shock wave, it's frequency is relatively low, never in excess of 20 Mhz and usually between 1 and 10 mhz. Because an EMP weapon functions by destroying an existing magnetic field it can be predictably optimized to hit higher frequencies that are far more damaging to modern circuits. But higher frequencies have less environmental penetration, and because EMP weapons are specifically designed to produce EMP in the Ghz range their reach is very limited, though they can easily devastate modern electronics that are within reach of the pulse.
If you really want to get an accurate perspective to what EMP which has been tailored to destroy modern electronics is really like, and not the garbage representation in the movie "the day after", watch The Matrix. In that movie they had a truthful representation of what EMP really will do when they used it to destroy the sentinels. Their EMP weapons did not reach out half way around the globe and blow out everything the way we have been trained to think a nuke will do, in reality - the reality they accurately showed, they had to allow the sentinels to get very close and destroy them at close range. And that was not for hollywood theatrics.

When it comes to penetration, frequency matters

The EMP generated by a nuclear weapon has a low frequency which has an enormous reach. So you can pretty much count on a large nuclear weapon to exert a big effect on electrical infrastructure even from a distance because lower frequencies travel better in the atmosphere and through liquids and solids. Since electrical infrastructure is large in size it can accept the low frequency and be affected by it. Historically however, all it did in Nevada during the nuclear tests was occasionally trip breakers and cause other minor disturbances due to interfering with power distribution, and in one case it supposedly damaged a rotary multiplexer (switch) at a nearby phone company. However, some skepticism exists regarding the damage to the switch, because the old rotary multiplexers were very high maintenance items anyway.
The main point with regard to frequency and nuclear EMP is that a ground or low air burst nuclear weapon, if large enough in size, has the potential to at least temporarily knock out power and damage phone systems within a 100 mile radius because it's frequency is low and gets good penetration, and also will couple with the long wires found in power and phone systems. And if the nuclear weapon is detonated at the edge of space, it's EMP gets an enormous reach and could potentially knock out power across the entire North American continent. But due to it's low frequency it won't have a chance of destroying small electronic devices even with the extra kick it gets from being detonated at a high altitude.

Because of the coupling limitations of low frequency, EMP weapons are specifically designed to hit higher frequencies than nukes

EMP weapons hit higher frequencies, and higher frequencies have advantages when it comes to destroying electronics, and severe disadvantages when it comes to penetration in the environment. The biggest factor is water vapor. Since a high frequency EMP weapon produces frequencies similar to what a microwave oven does, those frequencies get absorbed by the environment and converted to heat easily. In no cases have Ghz range EMP weapons been strategically effective outside of a two mile radius, because the atmosphere contains water, which soaks up the higher frequencies. And it gets worse than that - EMP weapons that have been designed to destroy electronics are very limited during periods of high humidity such as rain or fog, where their reach can be as little as 100 yards. So high frequency EMP weapons would work good against military targets such as aircraft carriers or the Pentagon in most weather, but due to their limited reach the civilian populations would have little to worry about because they would not be targeted by that type of weapon.

How average people should prepare for EMP and the loss of the power grid, if it gets destroyed

Have non gasoline power back ups. Solar panels are now cheap and easy. You can get solar power built and ready to go for only $2 a watt now fairly easily, so 500 watts of solar panels can be had for under a thousand. Go to a truck stop to get your inverter, they are cheap at truck stops, Make sure you get at least a 2,000 watt unit if you have 500 watts of solar panels. If you have a real small setup - 100 watts, just get a 500 watt inverter, bigger ones will waste your feeble power source. Wal Mart will have good ones for cheap that are under a thousand watts.

Just let it all sit around, don't bother installing anything when the grid is up unless you really want to go off grid right now, just wait until the disaster and believe me, there won't be ANY work to getting it all going when you need it because there won't be anything else to do but get it all going if you ever do need it. At that point you won't get gas for your car, it won't be available, so you can just rob the battery and barter for more batteries from other people to get your solar rig going the rest of the way. Sure, the batteries won't be ideal for solar, but after the end of the world, who cares? The key issue will be to at least have meaningful solar panels sitting somewhere, as well as a couple decent inverters.
If you were not within the reach of any high frequency EMP devices, all your electronics will be fine provided the EMP disaster was a real one and not something that was faked by having the cell network tell your Intel CPU to self destruct or your car to stop running. You will love the CFL light bulbs when running solar. Granted, I don't like how they were shoved down everyone's throats, but they are superb for survival lighting. A proper 500 watt solar panel setup will be enough to run a microwave to pop popcorn or heat coffee, along with a lot of other mundane things like radios and laptop computers. Plasma televisions eat power like crazy, you can forget those. Incandescent lights are an extremely poor choice when running solar. A good inverter on a 500 watt system can even run a washing machine if the batteries are adequate and you conserve power before wash day. 500 watts of solar can simulate fairly normal living conditions if used thoughtfully.
And one final thing - if you are running solar after the big disaster, make sure you pull the power meter off the house or you will end up back feeding all your solar power onto the now defunct grid, where Bobbie and Stan will gleefully try to run their plasma TV.

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