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I want to subject my product to large amounts of EMI to see what happens.

I figure I need the EMI to be broad-spectrum to be sure it will have the best chance of wreaking havoc.

However, I don't have any specialized equipment for generating or even measuring EMI, so what are some cheap ways I can do it?

Some ideas for generating EMI; no idea if these will be effective:

  • Using jumper cables and a car battery to make sparks (DO NOT do this in the vicinity of the battery itself because car batteries offgas explosive fumes)
  • Turning a heavy motor such as in an air conditioner or refrigerator on and off

One idea I read for sensing EMI is:

  • Listen to an AM radio tuned off-station

Any better ideas than these, especially as far as ways to generate the EMI?

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    \$\begingroup\$ Small tactical nuke. It's the only way to be sure. \$\endgroup\$
    – Passerby
    Commented Jun 5, 2013 at 21:28
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    \$\begingroup\$ Set up your test bench near a television tower and see what happens. A common problem near these towers is that car door remote control's don't function and some cars just refuse to start. Only solution is to push the car away and retry :o) \$\endgroup\$
    – jippie
    Commented Jun 6, 2013 at 5:35

2 Answers 2

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Tazer. Buy them from Amazon.com for as little as US$11.

The correct method for doing this is with expensive lab equipment that costs tens to hundreds of thousands of dollars. Anything less is a major compromise, to the point that you might as well have a Tazer.

We do our own ESD testing, which is similar to using a calibrated Tazer. And we will put our devices near known common RF emitters (Microwave oven, CB Radio, WiFi, Cell phones from various manufacturers). Of these tests, the ESD testing is the most informative.

Otherwise, we leave the EMI susceptibility testing to official labs, since we almost never fail this test.

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    \$\begingroup\$ I agree - ESD discharge guns will find any susceptibilities \$\endgroup\$
    – Andy aka
    Commented Jun 5, 2013 at 21:06
  • \$\begingroup\$ How close to the PCB are you supposed to fire it? I fired it about 3 cm away - no effect and my board kept working fine. Then I fired it 2 cm away, and it bricked the board! After some investigation, I found that it somehow blew out the battery protection IC, but the rest of the board was fine. The PCB was enclosed in plastic. \$\endgroup\$
    – AlcubierreDrive
    Commented Jun 8, 2013 at 10:52
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    \$\begingroup\$ @EvolvedAI This is the problem with an uncalibrated EMI/ESD source. You don't know how close to get. What you do know is that your battery protection circuit is the weakest link. Find out why, and fix it, to improve your design. Also, expect to destroy more stuff. Last month I destroyed an i7 based motherboard doing this. It gets expensive-ish. That being said, a million volt Tazer 2 cm away is probably too close. 10 cm is probably close enough for something in a plastic chassis. For ESD testing, I directly zap any exposed metal with 15K volts-- including connector pins! \$\endgroup\$
    – user3624
    Commented Jun 8, 2013 at 16:32
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All of the above are very completed. Just use a 115 vac relay. Wire the normal closed contacts in series with the coil. It makes a buzzer. The contacts spark making broad band Rf. We used this 35 years a go on my first job.

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