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Symbiotic Synth

A self-sufficient audio biofeedback device

The Symbiotic Synth is a low voltage oscillator that is powered as well as controlled by the human body.

It uses as the only power source the body temperature and drives with that an electric oscillator. The difference of the body to the environment temperature just can generates some millivolt. But with some tricks and some High Tech one can convert these and an astable multivibrator can be powered with that. It will oscillate in a audible range depending on the setting and with a connected headphone one can listen to the sound.
In attaching some light and temperature depending resistors to the circuit one can have variations of the sound based on the human body and its functions. The generated sound will change depending on breath, heart beat, skin resistance and body temperature.


With all that both is possible to power and to modulate a synthesizer with the own human body. And because the generated sound will stimulate the body function, too the Symbiotic Synth as an self-sufficient audio biofeedback device.

Schematic



Paper PCB

Parts

  • Resistors:
  • 3x 22 kOhm
  • Capacitors:
  • 1x 330 pF
  • 1x 1 nF
  • 2x 22nF
  • 1x 1 μF
  • 2x 220 μF
  • Diodes:
  • 1x low current LED
  • Semiconductors:
  • 2x BC547 transistor
  • 1x LTC3108 DC DC converter
  • Mechanical:
  • 2x adapter board SSOP 16pin
  • 2x 8 pin strip
  • 1x 2pin strip
  • 2x pin header, female 1×2
  • 1x jumpers
  • 1x mini switch
  • 2x mono mini jack socket
  • Potentiometers:
  • 1x 100 kOhm
  • Miscellaneous:
  • 1x Peltier element
  • 1x cooler
  • 1x airplane headphones

LTC 3108 module

Instead of using the LTC3108 with some transformer and some capacitors one can use a LTC3108 module like that, too:
https://www.ebay.com/itm/Body-heat-energy-harvesting-device/332328658257


Two Power Outputs:
Vout1 with selectable voltage and Vout2 which follows Vout1 in terms of voltage level.

Jumper Setting:

 1+3 Vout = 5V
 1+4 Vout = 4.1V
 2+3 Vout = 3.3V
 2+4 Vout = 2.35V

Pinout:

 S - additional storage element
 V1 - Vout1, up to 5mA of output current
 V2 - Vout2, up to 300mA output current
 L - LDO
 G - Ground\\