Using a microwave oven against an EMP as a shield

[MNwr786]

If I turn on my spectrum analyzer in the bedroom and go turn on the microwave in the kitchen, It will show a wide band of energy around 2.4GHz leaking out. They leak RF, a lot of it, even on the frequency it was designed for. But it is enough to keep the majority of it in the oven, so its safe for us and wifi routers.

If an EMP was mostly 2.4GHz, the oven may attenuate the EMP enough for your gadgets to survive. But EMPs max out around 500MHz and contain a lot of power on lower frequencies the oven was not designed for. I wouldn't trust it.

Metal tape isn't a great idea ether. I used to think so and often suggested it, but I've used enough of it shielding RF projects (amplifiers, active probes, etc) to know the glue backing is surprisingly good at keeping the foil out of contact with what you stick it to. When considering the frequency content of the EMP (under 500MHz), the capacitive seal the glue makes is not enough to appear as a short circuit to the lower frequency components of the EMP.

Then there is the thickness issue. You have to block two fields, the electric field and the magnetic field. Aluminum foil will block the electric field if it is sealed up tight, but it takes physical thickness to block a magnetic field. Non-ferrous metals can block fast-moving magnetic fields with opposing eddy currents (skin effect), but thats not good for the lower frequency stuff. unless (my opinion here) it is at least a couple mm thick.

Where you live will strongly influence your susceptibility to an EMP attack as well, so there is a lot to consider when deciding how much shielding is enough. What will protect my equipment being this far north is different from what someone in Texas will need to do to protect their stuff from the same event..

 

[user 6208]

I wonder if tapeing it up with metal tape will work.

It will act as a reflector if it is not grounded.

 

[poltiregist]

Whether the microwave will help with an EMP or CME , we may be able to lay to rest soon , as the coronal Mass ejections are picking up in frequency and strength . Right now the sun has put its milder erupting side facing earth but that will soon change in a few days . Considering what the sun was spitting out last week " multiple x classes ejections " , on its next volatile side turning to face earth , we may see some interesting days as the phone addicts and game addicts discover their fix is gone . Good prepper fun may lay ahead

 

[DrHenley]

A CME is a low frequency event, meaning primarily E3 component. It affects large circuits like power lines, metal pipelines, etc. The surge coming in through the wall socket is the primary concern for home electronics. And possibly anything hooked up to a cable line.

 

[AmmoCan88]

Yup as expected a whole lotta waffle about it. Do you have a leccy gizmo you want to protect from EMP? Will it fit in your microwave? If it is a massive thing like a genny (build a Faraday cage - it is very simple and need not cost mega fund) if it is small then just use your microwave and shut it in there ... DON'T TURN IT ON!
Want to check if your microwave oven is keeping waves out? Do you have a portable (cell or mobile phone)? Do you have a landline or a pal who can help? Stick the device in the oven and shut the door (do not operate the oven part!) and then simply call your number. If it does not ring or light up then your seal is good and MAY protect against EMP (there are a lot of variables okay the big one is proximity) and your detectors will hopefully work. There is ZERO point in shielding ANYTHING (phones, lappies computers that need a network as there will NOT be a network in many areas post EMP ) but Co meters, Dosimeters, digital thermometers and small but vital things may be saved.

No mater what I wish you logical thinking.

Don't rely on microwave ovens for protection against EMP.

 

[jimLE]

The only way I see using a. Microwave.is to completely cover it with aluminum tape.then ground it to a copper rod that's going into the ground.even then I have my doubts.

 

[user 6208]

Don't rely on microwave ovens for protection against EMP.

Why not?

The glass door is the only weak link. Often they are metal screens with holes in the range of 3mm. That's protection for frequencies lower than 100GHz.

You can add a sheet of metal over the door to block that if need be. Just make sure it's grounded to the same place the oven is.

 

[jimLE]

No the glass ain't the only weak point.the top most likely has a vent,that equals weak point.the same applys to back. Side and bottom sides as well.the door it self opens up.the door frame/jam another weak point.

 

[Robinjopo1]

I have my doubts about using microwave ovens. As I have stated, bug get into mine. Sooooo.???

 

[AmmoCan88]

Why not?

The glass door is the only weak link. Often they are metal screens with holes in the range of 3mm. That's protection for frequencies lower than 100GHz.

You can add a sheet of metal over the door to block that if need be. Just make sure it's grounded to the same place the oven is.

Don't use kitchen appliances for faraday cages. Use faraday cages for faraday cages. Either buy one or make one. If you're willing to spend the money a microwave oven costs, then spend the money on a faraday cage/box/bag instead.

To make a good faraday cage that can block electromagnetic radiation from EMP's and CME's you need serious shielding. Microwaves aren't built for EMP's or CME's in mind. This is sufficient reason for not relying on a microwave oven.

You also need to ground the faraday cage. I can ask you, how are you going to make sure your microwave oven is grounded well enough?
Make or order a box made of copper or aluminum. Place wood, plastic or other non-conducive material inside along the surfaces (so the electronics aren't damaged by a surge). Make sure it's grounded properly. Also protect it from moist, water, mould etc. (for the electronics you're trying to protect). Use plenty of faraday tape around the lid.

I've seen videos where people make their own faraday cage using a cabinet padded with foil, and then some faraday tape. Most likely won't work!

Against the extreme radiation of EMP's/CME's, you need extreme shielding. Optimally, you need METERS of LEAD or SILVER to protect against an CME, and there would still be no guarantee it would be enough.

 

[Proud Prepper]

Don't use kitchen appliances for faraday cages. Use faraday cages for faraday cages. Either buy one or make one. If you're willing to spend the money a microwave oven costs, then spend the money on a faraday cage/box/bag instead.

To make a good faraday cage that can block electromagnetic radiation from EMP's and CME's you need serious shielding. Microwaves aren't built for EMP's or CME's in mind. This is sufficient reason for not relying on a microwave oven.

You also need to ground the faraday cage. I can ask you, how are you going to make sure your microwave oven is grounded well enough?
Make or order a box made of copper or aluminum. Place wood, plastic or other non-conducive material inside along the surfaces (so the electronics aren't damaged by a surge). Make sure it's grounded properly. Also protect it from moist, water, mould etc. (for the electronics you're trying to protect). Use plenty of faraday tape around the lid.

I've seen videos where people make their own faraday cage using a cabinet padded with foil, and then some faraday tape. Most likely won't work!

Against the extreme radiation of EMP's/CME's, you need extreme shielding. Optimally, you need METERS of LEAD or SILVER to protect against an CME, and there would still be no guarantee it would be enough.

Which is why I use EMP Shield. My entire properties electrical system is protected as well as everything plugged into it.

 

[AmmoCan88]

Which is why I use EMP Shield. My entire properties electrical system is protected as well as everything plugged into it.

Unless that thing projects a force shield around your house, it will only protect against surges, not radiation.

If your home takes a "direct hit" from an EMP or CME, it's not gonna help you much.

 

[Proud Prepper]

Unless that thing projects a force shield around your house, it will only protect against surges, not radiation.

If your home takes a "direct hit" from an EMP or CME, it's not gonna help you much.

You should probably research what it does.

 

[AmmoCan88]

You should probably research what it does.

The EMP Shield protects against over-voltage. There's more to EMP's and CME's than over-voltage/power surges. The electromagnetic radiation contains energy that damages the electronic parts directly when hit, with protons, x-rays, gamma-rays...
The only chance you have if you wanna protect your electronics against a strong direct EMP or CME, is complete physical shielding with good conductor materials by the meters. Then you of course can be lucky and it happens to be weaker and a few centimeters will be sufficient, or it's so indirect that you will be hit with just a surge. It will not protect against a direct hit.

 

[Proud Prepper]

The EMP Shield protects against over-voltage. There's more to EMP's and CME's than over-voltage/power surges. The electromagnetic radiation contains energy that damages the electronic parts directly when hit, with protons, x-rays, gamma-rays...
The only chance you have if you wanna protect your electronics against a strong direct EMP or CME, is complete physical shielding with good conductor materials by the meters. Then you of course can be lucky and it happens to be weaker and a few centimeters will be sufficient, or it's so indirect that you will be hit with just a surge. It will not protect against a direct hit.

Wow. Or don't research.

 

[AmmoCan88]

I did read about their product. It says:

EMP Shield will protect all the electronics and equipment connected to your electrical system.

This is accomplished by shunting (shorting) the over voltage coming in from the grid and the voltage surges that are collected within your home.

Whether the source of electrons are from within your home or coming into your electrical system from outside the home (the grid), the Shield will see the surge and protect your electrical system. Our technology reacts in less than 1 billionth of a second. Since the shunting is completed incredibly fast, the over voltage is drained away from the equipment before the voltage can rise high enough to damage any equipment. We call this new technology SightSpeed™

It protects against over-voltage, not direct radiation.

 

[Proud Prepper]

I did read about their product. It says:

It protects against over-voltage, not direct radiation.

And how will you protect yourself from
a direct hit of radition from a nuke? If it destroys your electronics, would it not kill you?

 

[AmmoCan88]

And how will you protect yourself from
a direct hit of radition from a nuke? If it destroys your electronics, would it not kill you?

Shortly speaking, the radiation from an EMP/CME is strong enough to damage electronics, but not living things. Plus, the body can repair itself (within limits).

 

[Proud Prepper]

Shortly speaking, the radiation from an EMP/CME is strong enough to damage electronics, but not living things. Plus, the body can repair itself (within limits).

And how does it damage electronics?

 

[DrHenley]

And how does it damage electronics?

From the report by Medatech Corporation prepared for Oak Ridge National Laboratory:
The Early-Time (E1) High-Altitude Electromagnetic Pulse (HEMP) and Its Impact on the U.S. Power Grid
http://large.stanford.edu/courses/2019/ph241/rogers1/docs/meta-r-320.pdf
2.14 E1 HEMP Effects on Systems E1 HEMP peak field levels can be very high, and certainly there could be some devices within a system that have some vulnerability to such high levels. However, typically vulnerabilities involve the intermediate step of having voltages and currents generated on a conductor, and then that signal getting to the fragile device. The conductor might be deep within the system, such as wiring in the internal circuits, however a major concern is external cabling attached to the system, for two reasons. First, outside wiring can be very long, which tends to increase coupled signal levels, while internal wires are limited by the enclosure size. Secondly, the system enclosure and support structure, especially if metallic, attenuates electromagnetic fields and leads to lower coupling for internal wires. With a peak field of 50 kV/m, even a short “antenna” 10 cm (4 inches) long can mean a voltage of about 5000 volts, and it could be much higher for longer lines. Power lines, of course, can be very long. Other possible long lines include communication lines within a facility, such as network lines and phone lines. For power substations there are also the various sensing and activation lines used for the relaying process that maintains power reliability and tries to lessen harm to the power system from faults. With the advance of modern systems, and miniaturization of components, the normal operating voltages of systems tends to be a few volts, and so HEMP levels of thousands of volts or more cannot be good for the system. Also, the operating frequencies of systems, such as computers and various types of controllers, are such that an E1 HEMP pulse would cover many clock cycles. Thus the fact that E1 HEMP type pulses can have effects, as has been found in vulnerability tests, is not surprising.