How to Connect a Sensor with Audio Input and Output

A sensor is one of a basic component for capturing physical environment. You can get the change of light with a CDS photocell, you can measure the space with a distance sensor, and you can capture your movement with an accelerometer.

There are already several way to use push buttons in your projects (e.g. hacking mouse and keyboard, or Arduino, gainer, MCK). This probides alternative way to use faders with audio input and output. With a tiny circuit (which you will make), you can get sensor data with audio!

As side effects, it provides you with precious sampling resolution and frequency than the previous ways (i.e. 16bit to 8-10bit, 44.1KHz to 1KHz).

You can see examples of this with CDS photocell, and distance sensor (SHARP GP2D12).

We also present a sharker percussion with accelerometer and an application of this instructable from a sound performance project AEO.

All you need is just a sensor, some soldering, and some software.

Note: This is for analog voltage produce type sensors only. This will not work on digital type.

Note2: This is a series of "How to coonect with Audio". Please see others: Button, and Fader.

Note3: Allison and Place developed the SensorBox. The device accepted six sensor inputs and two audio inputs. The data from each sensor was carried as the amplitude of a sine wave, and mixed back on the two audio inputs. They did not provide its technical detail well, however their approach was quite same as this instructable.

Step 1 The Parts

Most of the components can be found at your local electronics shop (e.g. maplin in UK, RadioShack in USA, Tokyu-Hands in Japan). However you may need to use online electronic components store (e.g. RS in UK, Digi-Key in USA, Marutsu in Japan) for transformer and diaode.

1 Circuit board

2 Transformer / ST-75
The transformer adjusts the voltage. In this time, we use 'ST-75' from Hashimoto-Sansui. However other transformer could be used if its satisfy the specification (e.g. TRIADSP-29). Currently we try to figure out they could be used or not.

4 Germanium Diode / 1K60 (1N60)
The diode allows an electric current to pass in one direction.

3 2-point Power terminal
For audio input, output, and power.

1 3-point Power terminal
For sensor.

2 RCA AudioPlug
One for audio input and another for audio output.

1 Quad Cable
For circuit and connectors. The length depends on how long you want.

1 USB cable
For power.

1 Pair of DC connector
For power.

Comments

[leahbuechley]

cool instructable! Very useful, simple & elegant. It would be nice to see a video of the simple interaction that also included sound. Do you have any of those?

[jojporg]

hi, thanks for your comment! i just added "Uses? Shaker Percussion" as a (kind of simple :)) example of interaction. hope it works!

[leahbuechley]

awesome!