Where I'm at

This project began with exploring my surroundings with a pickup from an electric guitar. This component when coupled with an amplifier circuit responds to magnetic fields of all types and produces sound.

When working with static magnetic fields from normal magnets movement through the field is required due to the dynamic nature of electromagnetic induction. A number of resources are available to explain how this works in detail, but basically a conductor (such as the wire coil in the pickup I was using) when exposed to a magnetic field that moves relative to it (either through moving the magnetic field or the conductor) causes a voltage to be induced in the conductor. The amount of voltage induced is dependent on the strength of the magnetic field and the speed the magnetic field crosses the conductor as well as the amount of conductor exposed. This is usually amplified by using a coil of wire as the conductor which multiplies the amount of conductor exposed to the field.

Electrical current flow causes an electromagnetic field to be produced surrounding the electrical wires and components involved. This field also causes electromagnetic induction in exposed conductors. The difference with this setup is the magnetic field is dependent on current flow.

In Direct Current (DC) circuits the field can be created and destroyed by turning the current on or off. This creation and destruction of the field causes it to expand and contract which can induce voltage in a conductor without the need for movement of either component.

In Alternating Current (AC) circuits the constantly changing polarity causes a very dynamic electromagnetic field that is continually cycling at the AC system’s 60 Hz (60 cycles per second) frequency. This active electromagnetic field induces a steady and consistent frequency signal in exposed conductors. While the frequency is constant, the voltage level in the conductor is dependent on the the amount of conductor windings in the field and the strength of field it is exposed to (which is in turn dependent on the number of electromagnetic field sources and their proximity to the conductor).

The exploration of my environment began by walking around my immediate surroundings with the pickup and checking obviously electrical components to see the strength of electromagnetic fields.

Electrical wires and outlets produced a relatively small electromagnetic field while devices such as motors, monitors and computers created a larger field. While it was expected that I would find a significant electromagnetic field presence inside our well-wired buildings it was my outdoor explorations that provided the most surprises.

Power lines and transformer stations such as the one at Annabella St. at the Red River produce large fields that reach well beyond the physical dimensions of the structures that contain/support these electrical components.

In my consequential research i came across the work of Richard Box who planted hundreds of fluorescent tubes beneath a set of power lines. During periods of high electrical consumption such as at night the mercury vapour in the tubes becomes excited by the electromagnetic field located beneath the high voltage lines and causes the phosphor to fluoresce, providing a visual interpretation of the phenomena surrounding it.

Following this discovery I set out to replicate this experiment. I set up a transformer which when triggered would produced high voltage pulses of electricity. I managed to reach in the neighbourhood of 100,000 volts which jumped an air gap of an inch and a half. Using a compass to give me an indication of the magnetic field present I was able to find that the transformer when in operation had an electromagnetic field with a radius of approximately 8-10 inches. I placed a compact fluorescent bulb (still not electrically connected) an inch from the transformer and was able to see it flicker in unison with the transformer’s operation. This gave me a visual medium for expressing the electromagnetic field.

These fields are very much a part of our physical environment; a fact which is largely overlooked as it is not a presence that we are naturally equipped to sense. We require interpretation into a form our senses can register. My investigations up till this point have been to provide audible and visual cues to indicate the presence of these fields.

Next I will have to find a way to use this interpreted sensorial data to create an architectural project.