Transmitter / Signal / Receiver

T/S/R is a belt with four bright headlights projecting horizontally outwards around the wearer. An FM radio plays in the wearer’s ears. If the signal is strong, the lights project outward from the wearer. If the signal is faint, the headlights point downward to the wearer’s feet and the radio in wearers’ ears is replaced with the haunting crackle of naturally occurring low-frequency radio signals in their surroundings.

In the dark, navigating a space with light projected far outwards, wearers lose sight of their body, living several meters into their spatial future. Wearers become a server, seeking with pings of light - a specter in the dark. When navigating with light projected at their feet, wearers have no future to react to. Their light is not a probe but rather a beacon, announcing “I’m here” on behalf of both themselves and their surroundings. In the process, I hope wearers reflect on their relationship to natural spaces around them as they transition between intruder and native.

Fall 2020

The belt consists of four headlamps with attached servos, a 6V battery to power the servos and Hammond diecast box containing:
- Si4703 FM radio receiver
- ATTiny84
- 555 timer
- 9V battery
- 3.3 and 5 V voltage regulators
- 3.5 mm headphone receptacle whose input signal is controlled by a relay
- Very-Low-Frequency (VLF) natural radio receiver circuit and antenna
All four headlamps on the light belt are connected to the 555 timer that generates a light pulse every second
Servos connected to the ATTiny84 control the angle of each headlamp
The ATTiny84 is connected to the Si4703 FM radio receiver whose registers have been set to only detect stations above a set RSSI and SNR threshold
If the station the Si4703 is tuned to has a strong signal, then the servos keep the headlamps pointed outwards
If the station strength drops below a set RSSI threshold, the Si4703 seeks for another station of adequate strength
If there are no stations with strong enough signal nearby, the servos point the headlamps downward
Then the ATTiny triggers the relay to switch the audio input to the headphone jack from the FM receiver to the VLF receiver
The VLF receiver is based off of Charles Wenzel's Hum-bugged circuit
The antenna signal is passed through a 60 Hz notch filter to attenuate power line noise and then amplified through a dual op-amp to the headphone jack
A ground wire connected to the Hammond Box body can be tucked into wearer's waistband to ground the entire circuit
In the background, the Si4703 is still seeking any radio stations with adequate signal
If a strong radio station is found, the ATTiny triggers the relay to send the Si4703 audio output to the headphone jack again

Transmitter / Signal / Receiver

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