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detektor

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The detektor from micro_research makes audible both low and high frequency (LF and HF) electromagnetic emissions from all manner of man-made signal-sources such as power lines, tram lines, all electronic gadgets and machines, 2.4 GHz WIFI, cellphones, communication beacons and many more.

Developed as part of a project with Shintaro Miyazaki ( http://www.digicult.it/news/mapping-the-electomagnetism-detektors-by-martin-howse-and-shintaro-miyazaki/ ) the detektor was designed to make it as easy as possible to listen and record (using a digital recording device not included) wide spectrum electromagnetic signals. A coil provides a close-up window into the inaudible transmissions from all electronic devices and a built-in antenna allows access to higher frequency wide band emissions. You can switch headphone monitoring mini-jack between these, adjust volume, attenuate the high frequency signal and record (left and right) both LF and HF. The detektor runs from 3x AAA batteries.

The detektor differs from other electromagnetic sniffer options such as SOMA's Ether or the Elektrosluch in offering both "inductive" sniffing, and wide-band high frequency detection. It can be used to listen closely to devices and experience wider electromagnetic ecologies.

Image credits: Ioana Vreme Moser

Order

Price: 92 euros with free shipping worldwide.

13 in stock.

Sounds like

Earlier prototypes of the detector were used to make most of the recordings here:

See also: http://algorhythmics.ixdm.ch/?p=159

The detektor available here finalises and tidies up the design, also adding adjustable attenuation to the high frequency part of the circuit.

Rough guide

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Either low or high frequency signals can be monitored from the headphone socket (with antenna at top and sockets right this is the top minijack socket), with one switch (lower right) selecting low or high frequency domain. Both signals can be recorded as a stereo pair from the other (lower) socket. Low frequency signals are primarily in the magnetic field domain, so the coil (black object top left) needs to be placed quite close to the emitting object (for example, any electronic device such as a mobile phone, bank machine, digital recorder, monitor, LCD and so on). The antenna for high frequency signals is located top right and can barely be seen under the black soldermask layer. It should not be touched or covered with the hand as this will effect signal strength. The antenna will receive signals covering large distances and heavily effected by reflections and other effects from surrounding buildings, bodies and infrastructure.

The bottom left knob/potentiometer adjusts headphone volume. The top right knob controls attenuation of the high frequency signal.

The detektor is powered by three AAA batteries installed on the back of the unit. The power switch is in the middle of the unit.

Hardware

Schematic and design

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The schematic and PCB design (all licensed under the GPL) are available from:

http://1010.co.uk/det.zip

Parts list

Capacitors

  • 1nF x1 (0805)
  • 680pF x2 (0805)
  • 100nF x6 (0805)
  • 47nF x1 (0805)
  • 1uF TANTAL x4 (segor=TA1u0-35A SMD case A)
  • 47uF TANTAL x1 (segor case A or B)

IC

  • LED 0805 x1
  • AD8313 x1 (ebay)
  • OP07 or OP27 x1 (SMD-SO-8)
  • LM386 x1 (SMD-SO-8)
  • LM358 x1 (SMD-SO-8)

Resistors

  • 10R x3
  • 47R x1
  • 100R x1
  • 330R x1
  • 1K x1
  • 4.7k x1
  • 10k x4
  • 15k x1
  • 22k x1
  • 47k x1
  • 100K x1

(all 0805)

misc

  • 100k POTI x1 (segor=PT10MV-100k)
  • 10k POTI x1 (segor=PT10MV-10k)
  • steckachse (segor=5116 sw) x2
  • inductor (reichelt=L-11P 100M) x1
  • klinkenbuchse 3,5mm (reichelt=EBS 35) x2
  • battery pack (reichelt=3xAAA = HALTER 3XAAA) x1
  • switches (ALPS ebay) x2

PCB

Make your own PCB or purchase for 33 euros (with free shipping worldwide). Please contact for a discount for multiple orders:

Reviews and articles

The Detektors project has been featured in "The Routledge Companion to Music, Technology, and Education", and "The Oxford Handbook of Algorithmic Music" amongst others.

Mapping the electomagnetism detektors by martin howse and shintaro miyazaki/

Detektors. Rhythms of Electromagnetic Emissions their Psychogeophysics and Micrological Auscultation

Author: Martin Howse <m@1010.co.uk>

Date: 2015-09-06 10:00:54 BST

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