1133 User Guide: Difference between revisions

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===Formulas===
===Formulas===
The Formula to translate SensorValue into a sound pressure level is:
The Formula to translate voltage from the sensor into a sound pressure level is:




::<math>\text{Sound Pressure Level due to a 1kHz tone (dB)} = 16.801 \times \text{ln(SensorValue) + 9.872} \!</math>
::<math>\text{SPL} = (16.801 \times \text{ln(Voltage)) + 98.889} \!</math>
 
 
Where SPL is the sound pressure level due to a 1kHz tone in decibels.


===Formula Dependencies===
===Formula Dependencies===

Revision as of 20:46, 13 April 2017


Required Hardware

  • A 1133 Sound Sensor
  • An InterfaceKit or Hub to read the sensor
  • A Phidget cable
  • A USB cable
  • A computer

Connecting the Pieces

1133 0 Connecting The Hardware.jpg
  1. Connect the sound sensor to the InterfaceKit or Hub with the Phidget cable.
  2. Connect the InterfaceKit or Hub to your computer with the USB cable.


Testing Using Windows

Phidget Control Panel

In order to demonstrate the functionality of the 1018, the Phidget Control Panel running on a Windows machine will be used.


The Phidget Control Panel is available for use on both macOS and Windows machines.

Windows

To open the Phidget Control Panel on Windows, find the Ph.jpg icon in the taskbar. If it is not there, open up the start menu and search for Phidget Control Panel

Windows PhidgetTaskbar.PNG

macOS

To open the Phidget Control Panel on macOS, open Finder and navigate to the Phidget Control Panel in the Applications list. Double click on the Ph.jpg icon to bring up the Phidget Control Panel.


For more information, take a look at the getting started guide for your operating system:


Linux users can follow the getting started with Linux guide and continue reading here for more information about the 1018.

First Look

After plugging the 1018 into your computer and opening the Phidget Control Panel, you will see something like this:

1018 Panel.jpg


The Phidget Control Panel will list all connected Phidgets and associated objects, as well as the following information:

  • Serial number: allows you to differentiate between similar Phidgets.
  • Channel: allows you to differentiate between similar objects on a Phidget.
  • Version number: corresponds to the firmware version your Phidget is running. If your Phidget is listed in red, your firmware is out of date. Update the firmware by double-clicking the entry.


The Phidget Control Panel can also be used to test your device. Double-clicking on an object will open an example.

Voltage Input

Double-click on a Voltage Input object in order to run the example: [[Image:{{{1}}}_VoltageInputSensor_Example.jpg|center|link=]]


General information about the selected object will be displayed at the top of the window. You can also experiment with the following functionality:

  • Modify the change trigger and/or data interval value by dragging the sliders. For more information on these settings, see the data interval/change trigger page.
  • If you have an analog sensor connected that you bought from us, you can select it from the Sensor Type drop-down menu. The example will then convert the voltage into a more meaningful value based on your sensor, with units included, and display it beside the Sensor Value label. Converting voltage to a Sensor Value is not specific to this example, it is handled by the Phidget libraries, with functions you have access to when you begin developing!


For more information about Voltage Inputs, check out the Voltage Input Primer.

Testing Using Mac OS X

  1. Go to the Quick Downloads section on the Mac OS X page.
  2. Download and run the Phidget OS X Installer
  3. Click on System Preferences >> Phidgets (under Other) to activate the Preference Pane
  4. Make sure your device is properly attached
  5. Double click on your device's objects in the listing to open them. The Preference Pane and examples will function very similarly to the ones described above in the Windows section.

Testing Using Linux

For a general step-by-step guide on getting Phidgets running on Linux, see the Linux page.

Using a Remote OS

We recommend testing your Phidget on a desktop OS before moving on to remote OS. Once you've tested your Phidget, you can go to the PhidgetSBC, or iOS pages to learn how to proceed.

Technical Details

The pressure level of sound is measured in dB. The 1133 measures sound across a very wide range, with a frequency range of 100Hz to 8kHz and pressure level from 50dB to 100dB. The formula reports SPL (Sound Pressure Level), but the sensor is not sophisticated enough to be used as a substitute for a professional SPL Meter.

Formulas

The Formula to translate voltage from the sensor into a sound pressure level is:



Where SPL is the sound pressure level due to a 1kHz tone in decibels.

Formula Dependencies

It is important to note that measuring sound pressure levels is very complex and depends on factors other than only the perceived volume. One of the major contributing factors is the frequency of the sound source. Different frequencies of a sine wave with identical amplitudes will generate very different sound pressure levels. Other factors can be the distance between the sound source and the microphone, and even the type of sound source, such as speakers. The bandpass filter of any speaker can affect the output gain at certain frequencies without any change in the volume knob of the speaker. Electrical noise in the power supplied to the sensor can affect the output. If the power supply is very noisy, this will introduce an offset in the output. It is much more noticeable when trying to measure smaller sound pressure levels due to the very small voltages of the microphone being affected much more. As a result, the previous formula is only accurate for a 1kHz pure tone. At other frequencies, there can be up to an 8dB difference between the calculated SPL and the output of a calibrated Sound Pressure Level meter.

Sensor Response

The following graph is the response of the Sound Sensor to a 1kHz beep. The beep lasts 75ms. The 1133 has a response time of 1.40ms when placed 30 cm (11.9 inches) from the sound source. The output from the Sound Sensor reduces to normal over the next 80ms.

1133 0 Response.png

The output of the sensor can vary by up to 20 SensorValue in a pressure-stable environment. This is especially noticeable at lower output voltages. The best way to deal with this is to average a handful of reported values.

Phidget Cable

Analoginput.jpg

The Phidget Cable is a 3-pin, 0.100 inch pitch locking connector. Pictured here is a plug with the connections labelled. The connectors are commonly available - refer to the Analog Input Primer for manufacturer part numbers.

What to do Next

  • Programming Languages - Find your preferred programming language here and learn how to write your own code with Phidgets!
  • Phidget Programming Basics - Once you have set up Phidgets to work with your programming environment, we recommend you read our page on to learn the fundamentals of programming with Phidgets.