# Scrambling Pocket Calculators Made Easy With EMP Box V2

[Rostislav Persion] has for some time been interested in making small, portable EMP devices capable of interfering with nearby electronics. In these EMP devices, high voltage is used to create a portable spark gap generator, whose operation in turn creates electromagnetic pulses capable of resetting or scrambling nearby electronics such as pocket calculators.

His original EMP box designs relied on spark gaps constructed from metal screws threaded into a clear plastic insulator, but this newest design ditches fussy screw adjustments and relies on perfboard. By cutting out a single row of plated perfboard holes and soldering the high voltage terminals to each end, the empty holes in between form the essential parts of a spark gap.

It’s even adjustable: one simply bridges adjacent holes with solder to effectively decrease the gap. As for generating the high voltage itself, a DC voltage multiplier from Amazon takes care of that. Watch the device reset some calculators in the short video below.

Looking for high-voltage experiments that aren’t so sketchy? Get yourself a Van de Graff generator, some metal balls, and a little bit of oil, and make some art.

## 47 thoughts on “Scrambling Pocket Calculators Made Easy With EMP Box V2”

1. The Commenter Formerly Known As Ren says:

Is he doing this in a Faraday cage?

1. If not he could be interfering with cell phone, GPS, aviation frequencies just to name a few. Anyone of which could result in the alphabet boys knocking on your door.

1. OG says:

Given that he’s recording video with a phone (albeit with the camera turned the wrong way), the device must not be all that fearsome.

2. Ivana Humpalot says:

It is a broad spectrum signal. So the power is low. But GPS signals are weak yes, but I think the emp would not reach far.

A jammer made for making noise on the right frequency will reach further. Some just adds more to the background noise, but I think if you got a jammer that actually sends out pseudo random data with the right modulation on the frequency will reach even more devices.

2. Helios says:

I would love to see more DIY jammers and EMP. They’re critical in modern conflict, but the technology available to civilians is lacking. I wonder how this basic design could be improved, some kind of antenna or reflector? Adjustable capacitor for frequency tuning?

1. Nick says:

I’m thinking high-explosives, piezoelectrics, and jumbo coils.

1. Helios says:

That would be insanely cool. I’ve seen a few whitepapers on flux compressor design, but never any modern diy attempts.

2. ben says:

Reusable adhesive so they can be slapped against airbnb cameras for the length of the stay.

1. Sword says:

Deauth is simpler and more effective

1. Jim says:

And less likely to get you sure, fined, or jailed. Ask the dad that jammed his daughters cell phone.

2. How effective is deauth against a camera recording to local storage though?

A cheap camera with an sdcard can still record without network access.

An EMP would still be effective in that case

1. OG says:

But not this one, given that the guy is recording video if it from a foot away.

3. ytrewq says:

> I would love to see more DIY jammers and EMP. They’re critical in modern conflict

Military/industrial appliances are well protected against EMP devices, at least the ones not involving the use of nuclear power. If you build one of these toys, you have zero chances to use them effectively in any conflict against even the crappiest military, including the police, but can severely harm people carrying medical devices that for size and weight reasons cannot be properly screened. Please stay away from these “projects”.

1. Amessiah says:

Disagree, but point taken

1. Jason Cullen says:

As a millwright I can say with absolute certainty that this project is dangerous around pacemakers.

Solid state magnetic motor couplings are dangerous enough, an EMP…

Might wanna do your homework before you dismiss safety precautions out of hand.

1. Amessiah says:

Your certainly replied to wrong person

2. HaHa says:

Similar statement: As an Electrical Engineer I can say with absolute certainty that pushup bras are dangerous when cup size is above F. You should never be under a dangerous load on a lifting device.
It’s not wrong, but the qualifying phrase is irrelevant.

I remember building a spark gap generator with my 100 in 1 electronics kit in middle school. Used it to annoy my big sister. Worked like a charm.

3. Morberis says:

@HaHa

Says the guy who seems to have no idea that millwrights work with, the training they get, or the safety issues they need to know about.

3. doc says:

if some clown sets off my implanted defibrillator with this or a similar device then if I cause them to cease to exist it will be justifiable homicide. Things like this can be very dangerous.

1. Jan Praegert says:

Lets expand this by listing commonly types of functional electrical stimulation technologies: cardiac pacemaker, implantable cardioverter-defibrillator, cochlear implant, urinary bladder control, diaphragm pacing, fecal incontinence control and myoelectric prosthesis. And insulin pumps. (Did I miss something?)

So chance to meet a human that might react to EMP are quite high.

1. rpavlik says:

Not to mention tens/nmes – not implanted but electrodes with big wires (antennas).

2. Also spinal stimulator pain control implants such as Nevro HF-10 and HFX. and others.

2. Dan says:

Better start wearing an aluminum foil breast plate to meet ups, sorry for your luck homies

But mah Freee-dummmbbbbb

1. The Commenter Formerly Known As Ren says:

Freedom used to mean the “right to do what is right”,
now, it just means the “right to do whatever I want”.

1. Jonah says:

“Freedom: the power or right to act, speak, or think as one wants without hindrance or restraint.”
– Oxford

1. Patrick says:

You are correct, but I really like Ren’s definition. I’m going to start using it in the present tense.

4. Harvey says:

Shouldn’t all those implanted medical devices be well shielded and protected from electromagnetic fields? Considering this is a lot a stuff wireless connected to the internet. RC toys. It’s not just a stay away from microwave ovens thing anymore. Rules on paper, don’t make it safe.

Most of these EMP devices only have a range of a few inches. Just knowing that, and why, will be a dream-killer for most. Discussing these sort of things, point out undesired consequences, and limitations. The potential, and the vast variety of electronic devices to mess with. Wouldn’t you think that a portable EMP would have been done to death by now? Who hasn’t had a loud neighbor?

4. I can see why people would want to do this, but I really hope they don’t make a habit of it.

1. It’s a radio transmitter.

2. I do know several people who have implanted pacemaker and defibrillators, to whom devices like this are potentially dangerous.

3. Properly shielded and suppressed devices probably aren’t bothered, but these have become more the exception than the rule.

4. If you want to see a proper ESD testing gun: https://www.youtube.com/watch?v=5tciD21Q7Oc

5. K says:

I’m typically against not covering stories because they’re dangerous, but this crossed a line. These are ready-made portable units explicitly for interfering with devices, and as far as I know this isn’t for any research purposes. It is of course a fool’s errand to try to hide information about spark gap transmitters, but this is as accessible as a how-to article, including what you need to buy and where. I’m almost certain that the author and HaD are criminally liable for people following this design, at least in the US.

1. Helios says:

Eh, don’t be such a baby. Dabbling in dark arts responsibly is part of being a hacker. Devices like this have lots of uses, like bypassing electronic locks, and interfering with MCU security features. It only has a range of a few inches, so its hardly a weapon of mass destruction. He even put warning labels on them.

2. Sword says:

No information is not illegal unless classified.

3. This thing doesn’t even work unless it’s right next to the calculator. Way too low power, and it’s obviously unidirectional. Once again the inverse square law applies.

1. Zenith Star says:

Spark gaps are unidirectional?

4. Jim says:

This particular device is likely less problematic then the wrong spark plug wires on a typical car.

5. GEO says:

You got some case law to back up the assertion that HaD or the blogger are criminally liable for the actions of other people? I’d be real curious to see that.

6. Anomic Xtreme says:

Damn, and I was just about to upload my detailed tutorial on making m-80s lol.

1. MikeR says:

Popular Science had a diagram on how to theoretically build a large emp in the 90’s.
Had a large coil charged by caps and an explosive charge to rupture the coil to release the emp.

Surely this would be a lot more effective with a tesla-coil style resonant circuit ?
On the spark gap side, a spark plug is probably a longer-lived device than a bit of perf board. For EMC testing of engine controllers we used to put them in a pressurised but not rf-proof cylinder (a very thick glass wall).

7. paulvdh says:

This seems quite interesting for noise immunity testing of self built electronics. Having a built-in distance measurement would be a nice addition for this. Maybe a time-of-flight sensor works (as long as it does not get destroyed by the pulses themself), or maybe just a simple plastic slide out ruler

8. This is just a message I'm not dealing with your request for info says:

I think I remember reading making an actual EMP device is highly illegal as they are baffingly classified as weapons of mass destruction, in the us and Canada at least, nothing to stop people in more sensible countries experimenting

But let’s face it, regarding armong the civilian population, we are pretty much hopelessly outgunned and out equipped at this point. An armed uprising would be a bloodbath no matter how you work it

It could be argues there is a sort of equilibrium, and the government will engage in as much oppression as they can get away with. On that case more armaments of various kinds, preferably of a non lethal character of course, could make sense, merely helping to hold back the tide of disaster slightly, but that has benefit.

1. HaHa says:

All you have to do is ignore the last 100 years of insurgencies to repeat your gun grabber derp.

9. Casey says:

As a ham radio operator, i have questions. I can hear the FCC compliant transformer at the end of the street, and a lighting strike a thousand miles away. I’m not sure how dangerous this is, but it is certainly harmful to the rf spectrum. Sure, the FCC doesn’t actually enforce its rules, but that doesn’t mean this sort of thing isn’t harmful.

You aren’t only disrupting hard to disrupt things near by with the EMP, you are also disrupting easy to disrupt things far away with the RF. Utility monitors, medical pagers, etc. That will be easy to find using radio direction finding, if not used incredibly sparingly.

10. Shane E Randall says:

The Calculator turns back on and still displays 0 which makes me believe that this EMP is not really all that effective because a truly damaging EMP would erase the devices firmware that’s imbeeded inside the device and with it all functionality of the device.

In simple terms. The EMP didn’t brick the calculator it only interupted its power supply so I wouldn’t say it scrambled anything.

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