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CRITICAL MEDIA-
THE INVISIBLE REVEALED-
ONPRESENCE | PERCEPTION | NOISE
-RIAT 2016
“[The] space of death has a long and r ich culture.
It is where the social imagination has populated its metamorphosing images of evil and
the underworld: in the Western tradition Homer, Virgil, the Bible, Dante, Hieronimus Bosch, the inquisition, Rimbaud,
Conrad´s “Heart of Darkness”; in north west Amazonian tradition, zones of visión, communication between terrestial and supernatural
beings, putrification, dwath, rebirth, and génesis, perhaps in the rivers and land of maternal milk bathed eternally in the subtle Green light of coca leaves. With European conquest and colonization, this spaces of death blend into a common pool of key signifiers binding the transforming culture of the conqueror with that of the conquered. But the signifiers are strategicall out of joint with that they signify. “If confusión is the sign of the times,” wrote Artaud, “I see at the root of this confusión a ruptura between things and words, between things and the ideas and signs that are their representation.” He wonders if it is that cleavage which is responsable for the revenge of things; “the poetry which its no longer within us andwhich we no longer succeed in finding in things suddenly appears on their wrong side.”Marx pointed to the same disarrangement and rearrangement between us and the things in the fetishism of commodities, wherein poetry suddenly appeared on the wrong
side of things now animated. In modern history the fetishism of commodities rejuvenates the mythic density of the space of death –with the death of the
subject as much as with new-found arbitrairiness of the sign where by a resurgent animism makes things human and humans things.”
Michael Taussig, “Schamanism, colonialism, and the Wild Man:
A study in terror and Healing”, 1987.
INDEX
CONCEPTPRESENTATION
REFERENCESELECTROMAGNETIC SPECTRUM
SENSORSPRINTED CIRCUIT BOARD
ELECTRONIC DESIGNTECHNICAL SPECIFICATIONS
INPUTSOUTPUTSCONTROL
APPLICATIONSBIBLIOGRAPHY
CONCEPT
S I G N U M _The invisible revealed, shows an approach to natural and human-made frequencies, which by its wavelength are absent to our senses, but present in our daily environment.
Through this research is presented a seminar on perception, invisibility and acoustic and electromagnetic signals which for their quality, condenses a series of encrypted information and modulations difficult to interpret.
PIEZOELECTRIC TRANSDUCER (EKU)“Piezo” or contact microphone.Generates a movement of loads, induces a current generating a magnetic field.Its composition is a ceramic (barium titanium - anode) and a piece of metal (brass-cathode).Electrical signal at the output is of a similar character in amplitude and frequency to the original sound wave.Application: hydrophone, amplified percussion, friction, steps, water droplets, etc ....
COIL / INDUCTOR (COIL)Capturing electromagnetic field oscillations.Passive component of electromagnetic induction.> Intensity > E > EMAble to hear low-frequency power supplies engines near field, hard drives, etc ...Application: sonify electromagnetic fiel oscilations, transmission through thin walls, record mobile conversations from the speaker, feedback loops,find buzz in the studio, holes in the wall, etc.
BPW34 PHOTO TRANSISTOR (BPW)Light to voltage conversion through its silicon core, with an ultra rapid conversion rate.Maximum output voltage 0.5V7,5mm2 areaWorks on the high frequency domain 1014 HzApplication: Light to sound through mirrors, lenses, amplifying laser spy objects, listening the sky, etc.
IR PHOTODIODE (not on board, replaced by BPW34)IR light converter voltage (sound)500GHz 1013 HzListening infrared signals from remote controls, focus cameras, etc ... These oscillatiosn normally are at 33000MHz
LDR LIGHT DEPENDENT RESISTOR / PHOTO RESISTANCE(not on board, replaced by BPW34)Cadmium sulfideLight oscillations vary the strength of its coreWith more light - Less resistanceVaries from 50 Ohm +/- MOhmMuch slower than photodiode or solar cell
MICROPHONE CAPSULE (MIC)Amplify sound pressure oscillations. Resonance frecuencies of a room, standing waves,
SHORT LOOP ANTENNA (ANT)UHF VHF through germanium diodesAttached 2 diagram for the construction on the last pages.
LARGE LOOP ANTENNA (ANT)VLF-ELF, basically a very long copper wire (20m) isolated from ground and trees.
STEREO INPUT (EXR-EXL)3,5mm 2 Ch. stereo input jack for external sensors, offering the possibility to have the sensors not attached to the board and build external ones like hydrophones, seismic, water detector, etc...
SENSORS
CIRCUIT DESIGN
S I G N U M is a portable device designed to provide a clean, line level & micro controller friendly output signal to various input sensors: different bandwidth antennas, high impedance transducers, photosensitive cells, infrared/ultraviolet and visible light, sound pressure or line level.
ELECTRONIC DESIGN
S I G N U M performs a fully analogue difference operation between its input and reference output level, multipling by a factor of 10 times in the first stage -controlable by potenciometer- and 200 times magnification on its second stage, providing a controlled amplitude output line suitable to be safely connected to any audio input: sound card, computer or mixer.
S I G N U M provides the input signal a maximum magnification ratio of 2000: 1 and a signal-to-noise distortion of 0.007% THD.
The kit contains two amplifier circuits operating in parallel to accommodate different impedances of sensors and a final amplification for line output. The 4 sensors embedded on its surface measures close range electromagnetic frequencies, a central SMA antenna connector for long-range signals and an external line input via the 3.5mm jack to amplify self made sensors and physical devices.
It´s powered by a 9V battery or a supplied 1,3mm power jack to USB connector.
CHARACTERISTICS
S I G N U M Portable Analog Instrumentation Amplifier. Edition of 50 pcbVoltage gain 1 to 2000 (w/ ALPS potentiometer)Amplitude control (w/ ALPS potentiometer)Bandwidth set to 15.9kHz (w/feedback capacitors), or 100kHz (w/ caps removed)Line IN / Line OUT (w/ Jack 3,5mm)SMA Antenna InputSelf-centering output quiescent voltageBattery operation 3V–30VUSB to 1,3mm adaptor includedCurrent drain ≤160mAOperating Temperature -20˚C to +70˚CJunction Temperature +150˚CSize 70x70 mm.8 x 30 mm. metal stands
INPUTS
S I G N U M has an 2 chanel input for external sensors or audio through a 3.5mm jack at the bottom, to connect various devices wi-thout fear to damage the input of a mixer or soundcard.
In its central part it has a SMA connector -antenna input- and a Data IN and Data OUT, for 2 pin sensors, which are normally designed for microcontrollers.
It also includes various sensors embeded on the PCB: a photodiode (BPW34), a piezoelectric transducer (EKULKIT), an inductor (333J)and a data input/output
OUTPUT
S I G N U M provides a mono output to connect to external devices, via a 3.5mm jack. It is optimized for line level (1 Vpp), so you can seamlessly connect to any device that accepts an input line level. The output also works as a power amplifier of 1 watt, suitable for connecting to a headset or speaker.
To get an appropriate reading of the different signals and their correct measurement, it is important the orientation arrangement and distance from the sensor to the desired source, so it is advisable for each test to redirect or rotate the device, as many signals behaves in an exponential way.
CONTROL
The device offers two main controls via 2 potentiometers on top of the board.
The main gain or amplitude (AMP) control potentiometer of the device, its placed on the right side and the sense control (SNS) for the microphone and the R-channel of the external 3,5mm input (EXR) goes on the left side.
When turning the potentiometers clockwise to the right, you get the maximum sensing/amplification from the device.
The switch located on the top left magnifies the main signal by x20(xx)/x200(CC), so its important to operate this switch with care when you are switching between sensors or when you are working with a big P.A.
SHORT LOOP ANTENNA
APLICATIONS
S I G N U M can be used for various applications and in different environments, from the measurement and analysis of signals, to field recordings for sthetic purposes within the soundscape, as it has the unique ability to provide a wide sound pallete and hard to identify sounds. The devide its intended as an experimental tool for artistic praxis and educational purposes.
DOCUMENTATION
All documentation on Signum, applications, new registrations, modifications and experiences will be uploaded to the web with free culture license CC 4.0 BY_SA.
://victormazon.com/signumIn case you are interested to provide material and share new experiences send a mail to the following address:
