Anyone have any experience with any of the EMPShield products? I just picked up a couple to install on the antenna feeds into the shack but haven't used them yet. I figure it can't hurt to have some extra protection, right?

https://www.empshield.com/radio-protection/

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$339 ?  

You got hosed at that price.

Take it apart. Guaranteed there ain't nothing but an MOV or GDT in it and a couple of capacitors, similar to this:

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Their website is just a shit-ton of hype.

Buy a real lightning arrestor for a lot less, one totally proven by thousands of lightning events, including my own:

https://surgestop.com/coaxial-arrestors/index.html

Polyphaser is another proven brand--you won't find a cell site without a ton of them.

Lightning strikes within 100 meters or so are excellent EMP simulators. You don't see cars, pacemakers or electrical substations just folding up and quitting because of lightning. You don't need any special protections. Here is an excellent paper on the subject:

https://ris.utwente.nl/ws/portalfiles/portal/266317435/1570724829.pdf

I will say, however, having been a victim of a near strike on my house, that EMP does pose some dangers. I lost a bunch of TV HDMI ports that were not plugged into anything. So many that it was an overarching theme. I also lost several Ethernet ports that were plugged into long runs of CAT5 (the CAT5 acted as a big antenna). There were a couple of other random casualties, like a wireless printer, a remote control, crazy random stuff. But all the appliances, PCs, laptops, cars, and radios were fine (radios protected by aforementioned Morgan arrestors).

I swear these posts about this stupid crap random thing is done by their employees…thinking the MAGA conspiracist will buy them…

These posts happen every week about this snake oil.

One of the units that Art Bradley has recommended due to it's quick reaction time is the Polyphaser IS-NEMP-C0. I've seen it at a lot of different prices but The Antenna Farm seems to have the best price on them: Polyphaser IS-NEMP-C0

All of the above.

I wouldn't touch OPs products with a 10 foot pole at those prices.

Morgan Manufacturing and Array Solutions both make ICE-inspired/clone products which are well proven and work. I recommend that type of device over Polyphaser for HF antennas because the ICE design has a DC drain for the center conductor, and big HF antennas can build up a lot of static/corona. That's much less of an issue at VHF/UHF frequencies, and Polyphaser has a little better SWR/impedance performance at higher frequencies.

OPs stuff may work, or may be crap, but at 4 times the price of a Morgan, I'm not willing to find out.

Aside from the convenience of getting it all in one package ready to install, what justifies the $100 +/- price for the one pictured?  Are the components and enclosure that expensive?  This looks like a $20 part at best.  Maybe I'm just getting old.

Do you have any background in manufacturing? Doesn't sound like it.

Inventory, fabrication, assembly, test and inspection labor is probably on the order of $40/unit in quantity. Then all the material handling overhead. If they are making $40/unit profit after material, labor and overhead they are doing great.

But they certainly aren't rocket science to produce. That's why lots of folks trade cash for sweat equity. By all means build all you need. I built my own 2x6 RF switch for short money but I probably spent 3 days on fab, assembly and test.

I live in a faraday cage. I haven't done the math in a long time, but last time I checked .06 siding, And .03 roofing will keep the important stuff alive.

Take a Polyphaser unit apart. There is maybe $5 worth of parts in it including the case.

The EMP Shield is an over-hyped and overpriced snake oil. They claim the EMP testing they have done and their patent. I looked into it a bit. The only thing it will protect is maybe itself in a very strong EMP event. I don't understand how their unit placed at the electrical panel in an average house can protect the whole house from EMP. It may protect from surges and transients but an EMP????  I doubt any houses have enclosed and properly bonded metal conduits for all the wiring.
Regardless of what's at the electrical panel, the house wiring is long enough and well exposed to any electromagnetic interference.
You literally have to shield and RF decouple ALL the house wiring to sufficiently provide enough attenuation. Also, it would be more effective to place protection devices at each outlet or at each electronic device inside the house. Just thinking out loud......

Is your siding and roofing sufficiently bonded and continuously sealed to provide sufficient shielding? Do you have double door entry points with the doors shielded? How about shielded windows? I seriously doubt it.  You may get anywhere from 3 to maybe 10 db attenuation at some frequency ranges but it's not nearly enough to protect anything. Heck, even a thin but long gap between the shielding panels may act as a slot antenna thus allowing RF energy to enter the building. You need at least 50 db attenuation to call it sufficient enough for a hypothetical EMP event.

If I wanted EMP protection, I would probably spend the money on redundant gear that lives in a metal trash can or whatever people build.

In the event a major emp happens, the lack of power, cell and internet will turn society into a mess and you might want to start thinking about taking down and hiding your home antennas before people start thinking you are the new AT&T.

I am just worried about 5g emissions.





Any serious Carrington Event, we go back 200 years no matter what. Thats what the guns are for.

EMP is way overblown as a threat.

Read the lightning paper I posted above. Over the summer I took two strikes in 2 seconds, one 250ft from the house on the pole/transformer that feeds the house, on 50ft from the house on my wellhead. This was equivalent to at least 2 separate E2 hits. E3 hits are bad for long wires but not as hard on electronics. So it was a good test.

BLUF: some shit got hurt, but it was not a trip back to the 18th century, or even the 20th century.

The sum total of all my protections are:

- Leviton whole house surge protector
- Fiber internet service
- UPS on all TV, networking, PCs, and amateur radio equipment
- Coaxial lightning arrestors on satellite dish and amateur radio antennas
- Extensive grounding and bonding of the amateur radio gear

So nothing really special or outlandish, merely prudent. No shielding, no boxes, no tinfoil. The cars all live outside.

Everything except the TVs was powered up when the lightning hit, and the TVs that weren't were plugged into their UPS.

What got hurt:

- Two TVs lost all their HDMI ports, even ones that were not plugged in. One TV lost a single port. One TV was 100% OK.
- Lost a router (but I had a backup/spare).
- Lost an Ethernet port on a PC and a ham radio (but I had spares of both).
- Killed the TACO relay controller on my heating plant (that was ugly--no hot water).
- Killed the start cap on my AC compressor (might have been a coincidence, it died two weeks later).
- Killed a wireless printer that was plugged into a UPS.
- Killed one of 4 DirecTV boxes.
- Killed one of 4 DirecTV remote controls (that one was crazy).

So, other than the hot water issue, it was hardly a survival situation.

What I learned:

- I need to invest in some HDMI suppressors and also put Ethernet suppressors on all my long CAT5 runs (I have 6 of those in the house--not worth changing them to fiber).
- Buy and keep a spare TACO controller and boiler controller.

All in all, I am 100% unworried about EMP.

I think most thought processes that lead to EMP concerns involve solar events and electronic warfare, which would be much more widespread events.

If by "electronic warfare" you mean nuclear, high altitude EMP. There is no other type of EMP other than solar induced that would be widespread.

More to the point, as previously expressed, EMP is not going to do major damage to small devices, cars, etc. It's when long wires are involved that things get interesting. And these days we primarily find long wires associated with the power grid. Telecom is increasingly reliant on fiber and mmwave transport, which is a good thing. But the electric power grid is a giant EMP antenna.

So the real question is how well will the electric power grid hold up. Nobody really knows. We know at the micro level because generating and distribution equipment holds up well to lightning. We know this for a fact. But how will it hold up at a macro level to a widespread pulse? What happens when essentially a lightning bolt hits every protective device in the grid all at once? Nobody knows, at least nobody who is publishing in the open literature.

By all means secure your spares in a metal box or garbage can. That's all you really need to do, if you even need to do that (I have spares, but not in a metal container). And keep a generator, generator spares and sufficient fuel source for it handy. I'm set for a 90 day interruption. After that I'm living the 1800's life.

No background in commercial manufacturing, but I have a metal lathe and a 3D printer, and I have designed my own parts for several projects in metal and plastic.  Also made about 50 handmade knives.  I do understand the concept of economies of scale.

All that said, it's a box with off the shelf connectors on either side and a few components inside.  It even looks like the box could be cut from an extrusion.  When I look at something like that, I also tend to think about other items that likely involved a much higher overhead but sell at a much lower price.  That's why I am confused about the $100 price tag on that part, when you can buy something like an MFJ travel tuner for $150 that involves a lot more expensive parts.   2 tuning caps, a rotary switch and an inductor wrapped on a toroid core, along with a DPDT switch, knobs and a silkscreened cabinet, a grounding terminal and similarly, two off the shelf SO-239 connectors.  Plus paying employees to solder and bolt it together.

Yes, I know it's comparing apples to oranges.  But how can MFJ manufacture a MUCH more complicated product (with multiple moving parts even) with higher materials cost and all the same other requirements, like advertising, rent, utilities, payroll, waste disposal, insurance, etc and still profit enough for it to be worth it?   Is the MFJ product shockingly underpriced?  If it isn't, that sure makes the little lightning arrestor appear shockingly overpriced.

You don't have to be employed in the manufacturing industry to know when something doesn't add up.  This doesn't add up.

I suspect the bulk of their business is conducted with other big businesses who simply don't have any other source for the product, and pay it just because they have to.  So the price doesn't reflect the cost to manufacture it.  It's expensive just because it can be.  Probably hits some sweet spot where it's still cheap enough to their big customers that they won't make it themselves.

The one I disasembled was just two radiators air gapped.

But that's a 50,000 ft view of the problem. You have to consider the down and dirty side of the problem.

Imagine you got an order for 150 lightning arrestors. Also imagine that you are not going to do any of the work yourself, no sweat equity at all. You have to hire someone to order the material. Track the material. Inspect and inventory the material when it arrives. Pay the bills for the material. Make the assembly kits. Then you had to hire someone to assemble the kits and test the final product (the so-called "touch labor" component, everything else is "overhead labor"). There's got to be an inspector to inspect internal assembly quality and final assembly quality and to sign off on the test results. You also had to invest in the equipment and write the procedures to test the final product. That same person that did all the material acquisition for the actual product has to order, inspect and inventory the material for the packaging of the product for shipment. Then you have to pay someone to take product orders, do billing, accept payment, do the books. Someone has to be paid to pack and ship the product. And throughout all this there are exceptions that need to be handled. Discrepant material that has to be discussed with the supplier, returned to the supplier, corrective actions taken. Product that doesn't pass inspection and that needs rework. Product that doesn't pass test and either needs rework or has to be scrapped thereby losing all your investment in it. Payroll has to be processed. Credit card processing costs money. Web sites cost money. Taxes, HR, training, insurance and a dozen other things that are involved in running a business, even a mom and pop garage operation, all cost money. Even if you don't have an "HR" department and you are hiring day workers as contractors it's still HR in practice and man-hours are expended doing it.

Can one or two people do all this? Certainly, but eventually you realize that maybe you'd like to actually earn some money. That's when you decide what your time is worth.

Do people gloss over a lot of this stuff or forget to take it into account when they are making and selling products? They sure do, and that's why they either decide it's not worth it and/or suffer a reputation for poor product and poor quality.

Sorry, but you are not adding it up correctly. The bulk of the cost in these simple devices, and both the lightning arrestor and travel tuner, is overhead, followed by touch labor, material being a distant third. They only seem dramatically different. But when you consider the amount of time to source the raw material and do all of the overhead functions necessary to produce and sell products is very similar across both devices then you are only seeing the very minor differences in touch labor and material cost.

Also, MFJ undoubtedly has a massive economy of scale thing going on compared to Morgan and Moran's owner, KF7P. MJF is doing millions in business every year. I doubt Morgan does $100K. That allows the overhead to be amortized to a much greater extent over the entire MFJ product line, which is huge, so that's a major reason the travel tuner and every other MFJ product is so cheap. The other reason is because MFJ skimps on employee training and QA. This is why they have the reputation they do. Many of their designs are really great, and their prices are really great, and as long as you don't mind having to do their QA for them, their finished products are really great, except that you finished them! You are trading sweat equity for the bottom line just at the consumer end of the road. When you are dealing with onesey twosey type quantities that's fine. When you need to build 100 units a month in inventory, or a 1000, or 10,000, you can't do that.

You say you make knives. How much would you sell one knife for? The material cost you almost nothing. Maybe you are making them out of old leaf springs. But you sweated blood on that thing for 40 hours to make it what it is. And you used up how many sanding belts and how much polishing compound and how much electricity? Or did you forget about shop consumables? How did you advertise it? Posting to forums is "free" but costs you more time. Taking and fulfilling orders, more time. You didn't want to pay for credit card processing so you are using Venmo, but Venmo charges merchant fees, too. Everything adds up at the end of the day. If your business is to survive then prices must not only cover your REAL costs, but also generate enough profit to provide the motivation to continue. And, finally, your prices must reflect supply and demand. Clearly Morgan, and MJF, have priced their products correctly because they are making enough money to continue to be both able to and motivated to make and sell their products.

They also have to price them to motivate purchasers as well, and that pricing has to account for the customer's perception of value, inaccurate though it may be.

I researched this previously - here's the patent:

https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/10742025  (left cold - it's a PDF for it).

I posted this in another forum:

If you look at the diagrams (and descriptions) it appears that all this is, is a collection of surge devices between phases /  neutral / ground.  Most likely it's a collection of TVS diodes, probably something like this:

https://www.mouser.com/ProductDetail/Littelfuse/15KPA120A/?qs=MLCmBfHNlR5528SJT7SrPg%3D%3D

So it's a fairly simple design that uses off the shelf parts.  From what I can tell, it's not supposed to shield your devices in the house from a direct EMP hit, meaning if you are in the danger zone, the field strength will just be everywhere and everything will be hit unless they are in a faraday shield.  I believe the intent of this is to address only the power feed coming into your house - which would possibly work if the actual EMP would not have much influence of other devices due to proximity, as it would shunt (quickly) any large voltage surge generated by the E1 to ground.  It appears that this device is a combination device to address EMP as well as standard surges genereated by system imbalances and lightning strikes.  Considering they charge what they do for it, they're making a killing compared to parts / assembly cost.

Most solid-state devices for surge suppression have too much capacitance for RF feedlines, which is why gas tubes are still the norm for that application.

I know, it's my funeral.  But I bought some cheap bulkhead mount gas discharge arrestors from Amazon the other day.

They have great reviews, but without getting a near strike, I don't know how you could actually evaluate them.  Maybe you could test them with a BBQ ignitor or something.  

XRDS-RF UHF Coaxial Lightning Arrestor SO239 Socket Bulkhead UHF Female to Female Coaxial Connector for CB Ham Two-Way Radio Base Antennas https://a.co/d/8SRcvNh

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No all gas discharge tubes are the same. They are rated for different voltages. Activation time is measured in nanoseconds but it's important to make sure the time is measured and published by the manufacturer. For HF bands, you can easily build your own protectors. Just use gas discharge tubes, quality ceramic capacitors (for DC blocking) and a combination of DC bleed coils and resistors (~ 300-500 kOhms). All parts can be purchased online for a lot less.

Also, gas discharge units alone, don't provide DC blocking and static bleed. This is why I like and recommend Morgan Mfg protectors. They come with all 3 protection devices inside the box. Static bleed coils (and resistors) are a great feature to reduce static noise during rain, snow or wind (in low humidity environments). Polyphasers don't have this feature.

I was planning on getting a coax "tee" connector and soldering a 1M resistor inside a PL259 for a bleeder.  I will need it with my eventual vertical but my present antenna EFHW transformer is a short at DC (IIRC).  For DC blocking you need a series capacitor on the center conductor?

ETA I found this ARRL paper detailing how to build one and what component values to use.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://archive.arrl-nfl.org/wp-content/uploads/2018/03/Lighting-EMP-Arrestor.pdf

Yeah, the formula for building these things is pretty well known.

Morgan has a nice little paper explaining their approach and how it compares to Polyphaser:

https://surgestop.com/ewExternalFiles/Morgan%20Manufacturing%20Corp%20Tech%20Bulletin%20Morgan%20Vs%20Polyphaserv2.pdf

The schematic from the paper:

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I have a Morgan M-301 1KW unit that died, probably due to a nearby strike. Looking inside I find the resistor is a 300K 1% 2W. The GDT has no data on it but is an axial lead type device and the paper suggests a rating of 400 to 1000V. It looks small, and it looks burnt at the tip (Morgan says their GDTs never burn because of the coil but that seems doubtful). The two cap's are 6.8uF 3KV ceramic disc. Most disturbing, however, is the fact that they are Russian surplus!!! That's a bit disappointing The coil is 32 turns of 20GA enameled copper. Not sure what the core is but I measured it and it's damn close to an Amidon FT-82-43. With that assumption and using this calculator that works out to 500uH.

I need to take apart a 3KW Morgan Arrestor and see what's in there.

Pic's of the 1KW unit:

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That gas tube looks like a neon bulb.  What's the coil for?

Please read the Morgan paper.

Ah, so the inductor is a choke designed to pass DC current to ground while blocking RF (confining it to the center conductor of the coax)?  It also seems like they are using the gas tube to handle the discharge from the field collapsing in the inductor after a large DC voltage is applied and removed?

I'm guessing the values for the caps and the inductor are chosen to have a minimal impact on feedline impedance.

Wow spicy crew! No, its not my product, I just want to try different things at times and figure it cant hurt. I found stackable coupon codes and got a lot off so gave it a shot. Everyone saying get lightning arrestors I already have them too. So basically I got both.

You can't "try" a device like that. You don't need both. If you got such a great deal on them maybe you can make a profit on eBay.

Well it's installed and being "tried". Guess if anything bad ever happens I won't be able to reach out and tell you if it worked or not. But, i'm willing to take a shot just in case.

2 is 1, 1 is ?

Whats inside the box

At one time Bud made cast aluminum project boxes with chassis RF connectors already installed, I got a couple with BNCs for something I was working on, I wonder if that's what those are in a larger size with SO239s. Or probably lower cost chinesium now. Piece of copper wire, a gas tube, and a 1000% markup along with a prepper-bait name and marketing, and voila, easy money.

I'm just not crafty enough to come up with the marketing to take money from the prep hordes. My best idea (which is actually real and useful) is not something I can make myself, and I can't get any interest from the manufacturer to make it

So they pot the entire insides to make it difficult to find out how bad a scam it really is. So very unsurprised...

Look at the patient I shared above - it contains all you need to know.

I just read the patent. It is total shit. It describes everything and nothing.

Column 12, line 51: "The system 200 comprises a plurality of shunt assemblies 202, 204, 205, 206, 207, 208 connected between various combination of power lines. A shunt assembly may also be referred to merely as a "shunt".

Column 12, line 65: "Each shunt assembly 202, 204, 205, 206, 207, 208 is properly called an "assembly" in that is comprises a plurality of shunt devices, such as metal-oxide varistors (MOVs), gas discharge tubes, and combinations thereof, as well as other mechanical, electrical and ionization discharge devices."

In other words our patent does not describe our invention specifically but instead literally describes every other protection device ever built by anyone ever. Gee, why don't they just file patent infringement actions on literally every company that makes an EMI, RFI, surge or "EMP" filter?

Our patent system is badly broken.

Yep - meaning they are selling smoke and mirrors, but you already knew that!

Then why does Art Bradley sell all kinds of stuff meant to protect small items from EMP, including items like vehicles that wouldn't be connected to any grid?  He even advises to drape EMP cloth over your generators, and EMP-proof the red dot sights on your guns (literally).

Tone doesn't come through well in text, so to be clear I'm not arguing with you, this is an honest question.  You are clearly a SME, and Dr. Bradley is supposedly one as well.  Your opinion and his are diametrically opposed, not just differing by a shade.

Who is right?

Who stands to profit the most? Thats who is wrong.

Product reminds me of the old Maxxcom fully automatic antenna tuners back in the 80's. Potted of course with epoxy resin. Had a circuit board in the potting material covering the actual active element which was a rather large 50 ohm resister. So a dummy load with two terminals on the side to connect your wires (any length) with an SO239 for input. They touted how fast this antenna tuner was. They claimed millisecond times as I remember. Of course lots of folks would say how satisfied they were with them. A good SWR from 160 to 6 meters. Pretty much flat. People will buy anything if marketed well. I bet a good pitch man could sell a 5 gallon bucket of mule piss.

lol $430 for $25 worth of ferrite beads... lmfao

Exactamundo!

The problem is that EMP is an incredibly complex issue and that most good information on it is classified. However, my own experience with lightning-induced EMP last year caused me to find this wonderful paper on that subject:

https://ris.utwente.nl/ws/portalfiles/portal/266317435/1570724829.pdf

I posted it above but you probably haven't read the entire topic or that paper.

TLDR: it turns out lightning is an excellent E1 and E2 type EMP generator. And, since lightning rarely causes significant EMP-type effects, we can rest assured that our radios, cars, electric shavers, dot sights, whatever, do not need to be stored in specially shielded containers. Nor, in most cases, do they need any kind of special, or even non-special, protection. Common, ordinary, whole house lightning protection, UPS units, and other types of lightning and surge suppression filters are all you need. Either that, or just simply disconnect the devices from all cables. Because it's the cables that are the antennas for EMP, and the longer the cable the worse the problem gets.

And, as noted in this topic, when you compare the snake oil EMP "protection" with garden variety lightning and surge protection, you find that the "EMP" devices are either no different or even substantially worse performing than the standard, garden variety stuff.

Bottom line:

- If it's convenient there's no harm in storing stuff in metal containers. No special grounding is required. You probably don't need to, but it's cheap peace of mind.
- If it's not convenient there's generally no need to worry anyway (read the lightning paper).
- If you have things that have long cables attached to them (coaxial antenna cables, power cables, Ethernet cables), putting plain old surge protection devices on those cables where they enter the valuable electronics is worth doing, but don't overspend on anything labeled "EMP blah blah blah"
- Whole house lightning/surge protection is worth it (but again, regular stuff from Leviton, Siemen, whoever, not nasty EMP snake oil devices).

If I had had HDMI surge protection on 3 of my 4 TVs, and Ethernet surge suppression on two specific long Ethernet cable runs, I would have survived my lightning EMP experience with almost nothing in the house being damaged. I had plenty of power line protection at both the entrance (whole house surge) and point-of-use (UPS units) and nothing took a hit via the power cable.

Finally, to put a really fine point on it, lightning does not simulate E3 type EMP. But since that primarily effects the miles-long power cables you should be well protected from that by infrastructure that exists at your local power substation.

No, I've read the entire thread and that paper.  I've also read all I could find on EMP that isn't classified, long before today.

Apparently the verdict on Art Bradley is that he's a shyster who lies about EMP for money (implied in this thread by BLKVooDoo and aa777888-2), but nobody in the community seems to want to say that explicitly.  I'm trying to understand why that's the case.

Because we've done tests on items with EMP generators. There was a test years ago where they subjected 20 modern vehicles of different makes and models against varying EMPs to see what the effects were, to try and test the common belief of only old direct injection, mechanically controlled vehicles would still work after a nuclear detonation.

The results found exactly what we suspected: nothing happened. Most vehicles were completely unphased by the pulses, with the most dramatic effect being a few stalled out and had to be restarted. But none suffered irreparable or even significant damage.

EMP has become the new hot prepper buzzword, particularly now since we have even more electronics than before and you don't even need a nuclear detonation to trigger one. It's an invisible force that can act and render anything electrical inert, as what common belief shows. The truth, like many scientific ideas, is much more nuanced and the answer is often "It Depends", as is typical in this field. That complexity has led to a lot of snake oil salesmen coming up and selling devices and gear to others. We see it in body armor (AR500 Armor amongst others), rebreathers (MIRA Safety), and more.

Having worked with Art directly, I can state in no uncertain terms that he knows his stuff. He's also tested a bunch of stuff on the market and has designed his own stuff, too. I'd trust his judgement on such things. Suffice to say Art makes a good living working for NASA so his side gigs aren't his primary income.

That having been said, there's a point of overkill such that if you have to take such dramatic measures to EMP "proof" your stuff, it's easy to forget that if a nuclear EMP device is detonated over the US by an adversary, WWIII has already begun and you should have bigger concerns. Solar storm, CME kinds of EMP, sure. Lightning, sure. Those are "known" threats that can, for the most part, be mitigated.

They won't say that explicitly because it isn't true.

Fear marketing $25 worth of ferrite beads for $450 is pretty shitty if you ask me. He may know his stuff, and be a nice human to you. But come on...

Art What-his-name's:  $325

Poly Phaser:  $125

Sounds like all you need to know.  

Nobody wants to write something like "Art is a shyster" because that then makes them a target for lawsuits.

However, and as is plainly evident in this thread, nobody is shying away from pointing out the facts:

1. Art's stuff is way overpriced compared to identical stuff.
2. Most prepper claims about EMP have no merit when compared to scientific papers on the subject.

Take from that what you will. I and others will not be trolled into writing stupid shit (nice try by one of you, who shall remain unmentioned but who is all too obvious...)

In addition to the lightning paper we have the fabled EMP Commission report: http://www.empcommission.org/docs/A2473-EMP_Commission.pdf  Together they are the two best unclassified and reasonably reputable resources we have available to us. The EMP Commission report reads a little breathlessly, but if you consider it dispassionately it basically says the sky will NOT fall. For instance, the part about vehicle effects:

Now one might reasonably argue that today's vehicles have even more electronics and therefore should be even more vulnerable. However, as someone who has built the most complex systems imaginable for the last 40 years, I'd argue the exact opposite is true, that more modern vehicular electronics are even more robust than their naughties counterparts. And throwing a few ferrites on your automobile battery lead is not going to change things in any significant way.

So far the only thing I've been disappointed in are the HDMI inputs on TVs. Whatever ASICs they are using on those are very vulnerable!

I've found a a few things that Art has on his web site for less money elsewhere. That's not a huge surprise to me. Volume matters and I seriously doubt Art has much.

Here's another document that everyone should take the time to read: https://www.cisa.gov/sites/default/files/publications/19_0307_CISA_EMP-Protection-Resilience-Guidelines.pdf

Further, while I consider Art a prepper (you would too if you saw all the crap he has in the trunk of his car), he also has the technical expertise to back up his claims. He is one of the primary authors on NASA's handbook for spacecraft electronics design and he was asked to be part of that because of his expertise with, amongst other things, EMP. So, you can arm-wave all you want but he does have both experience and is known in the field by other experts.

BTW, Art is also a gun guy. He and I took a couple of handgun classes together. I won't mention he took the first class with a Kimber 45 which surprisingly didn't fail on him.

As for cars and EMP, if I had to throw ferrites on various things to keep my grounded-to-the-frame HF radio from causing problems with my car's electronics, I'd say there will be some issues with my vehicle should a nuclear EMP end up happening. Having to restart my car to get it going again is going to be the least of my worries if that happens, though. We're all pretty much screwed at that point.

As I recall, you did a post a while back where you detailed a bunch of stuff that was affected by a close-by lightning strike. I've had a TV get toasted and a microwave oven get blitzed by a close-by strike. One other area to keep track of is USB ports on computers and laptops. One of my laptops had one of the USB ports stop working (along with the touch pad) down in Puerto Rico because RF was getting back into it from my team mates HF radio.