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Forum section: electronics / beginners

author: pranav
author_rank: Contributor
timestamp: December 27, 2017, 01:01:34 pm
content: ..

author: danadak
author_rank: Super Contributor
timestamp: December 27, 2017, 01:03:57 pm
content: EMP Definition/characteristics -https://en.wikipedia.org/wiki/Electromagnetic_pulseRegards, Dana.

author: Zero999
author_rank: Super Contributor
timestamp: December 27, 2017, 01:55:26 pm
content: It's also illegal and asking how to do it, might be against the forum rules. I will ask a moderator.

author: Belrmar
author_rank: Regular Contributor
timestamp: December 27, 2017, 03:39:52 pm
content: every discharge trough a coil creates a emp, but depending on the topology of the inductor it will have different characteristics.also...Why the hell you want to build something that can damage electronics

author: pranav
author_rank: Contributor
timestamp: December 27, 2017, 03:47:03 pm
content: It's purely for educational purposesIt's too powerless... I had to place the electronics on the coil to see full effectIt's also bulky...Sent from my Lenovo S850 using Tapatalk

author: EEVblog
author_rank: Unknown
timestamp: December 28, 2017, 12:21:04 am
content: Quote from: Hero999 on December 27, 2017, 01:55:26 pmWe try not to assume bad intentions here.For example, modifying a Casio watch to trigger a relay is commonly used to trigger a terrorist explosions. On the other hand, someone may have a legitimate use to trigger explosives because they have an explosive license and want to do it for some legit reason. Or they simply want to turn on their pool pump or something.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: December 28, 2017, 01:16:16 am
content: The "EMP generator" things I've seen floating around are mere toys.The impulse isn't anywhere near useful, whether for testing purposes (it won't conform to any particular standard) or for destructive purposes (it's weak, slow and short range).And if you're that close to a device, you can damage it much faster with a hammer...So, I would suggest directing consideration towards commercially useful transient generators (that are often destructive, as intended!).That said, it's hard to beat sparks. A high voltage power supply buzzing into a spark gap is quite effective. ESD is very destructive, having a risetime of nanoseconds and a peak current in the tens of amperes. A good commercial design would start with a HV supply (adjustable, since ESD is tested at various starting voltages, for various purposes), charging a capacitor through a large resistor, and discharging the capacitor through an RLC network that delivers a characteristic waveform (it's not just a resistor, by the way, despite what the equivalent diagrams show -- that would be preposterous, as the waveform has a double-peak sort of waveform, not a simple RC discharge).For higher energy tests, there's lightning induced surge. This is usually a modest size film capacitor (say 20uF) charged up, then dumped into an RLC network which is coupled to the load. Charged to several kV, that's a fair slug of energy, and it's delivered in mere microseconds!There are also ringing and RF-burst tests, for various applications (mil-spec bringing some of the more unusual ones). The generators may be similar to the above examples, but with different RLC networks to shape the waveform, and different charging and switching circuits to achieve the required pulse rate.RF-burst systems have the most promise for directed energy applications, as microwaves (for example) are easily manipulated with compact antennas, waveguides, reflectors and so on. Pulsing a commercial oven magnetron gets you a fairly clean 2.45GHz (at least a few thousand cycles worth, say, if you do a few-microsecond tone burst like old school radar sets used). Clean isn't necessarily what you want; wideband chirps, wavelets and impulses have more use, as they aren't dependent on the EUT having a lucky susceptibility or immunity (depending on which side you're working from) at some particular frequency.These are much more difficult to generate though, and may run into concerns about import-export law(!).The simplest wideband impulse generator would probably be a spark gap inside a ridged horn or biconical antenna. Indeed, air sparks are amazingly high bandwidth -- In the late 1800s, J. C. Bose researched frequencies up to 60GHz using mere spark gap sources!Tim

author: pranav
author_rank: Contributor
timestamp: December 28, 2017, 05:21:28 am
content: Quote from: EEVblog on December 28, 2017, 12:21:04 amThanks.. Actually I want to test resistance towards these types of burst of various appliancesSent from my Lenovo S850 using Tapatalk

author: pranav
author_rank: Contributor
timestamp: December 31, 2017, 12:32:33 pm
content: Quote from: pranav.appu.472 on December 27, 2017, 01:01:34 pmHow to make sure that it is EMP