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diff --git a/source/measure.markdown b/source/measure.markdown deleted file mode 100644 index 0c85df5..0000000 --- a/source/measure.markdown +++ /dev/null @@ -1,102 +0,0 @@ -% Measure -% -% - -About -===== - -This Activity draws a picture of the sound heard by the internal -microphone or of the signal present on the microphone socket. More -specifically it draws a graph of this input versus time, the input is on -the vertical axis and time is on the horizontal axis. That is, the -laptop functions like a machine called an oscilloscope. - -As well as graphing signal as a function of time, Measure can also graph -as a function of frequency. - -The XO-1 laptop is only capable of mono input, the XO-1.5 and XO-1.75 -are capable of stereo input on their microphone socket and can graph two -signals at once. - -Using -===== - -1. Select secondary toolbar - allows the Activity's Journal entry to be - renamed -2. Select secondary toolbar - measurement settings -3. The selected input type - Sound (AC voltage), resistance or DC - voltage -4. The time scale -5. Freeze the display -6. Capture sample now - saves an image of the wave in the Journal -7. Stop - exits the Activity -8. Invert - invert the display -9. Use these sliders to control the sensitivity -10. The settings that are selected - -The secondary toolbar - measurement settings - -11. Sound - use this setting with the internal microphone, external - microphone and external AC signals - -12. Resistance sensor - use with external resistive type transducers - -13. Voltage sensor - use with external sensors which generate a voltage - -14. Time base/frequency - graphs the signal vs. time or graphs amplitude - vs. frequency - -15. Sample interval - a text file 'Measure Log' is saved to the journal, - it contains one sample per interval - -16. Starts/stops saving a text file 'Measure Log' with measured values - as readable text - -17. This feature is not working well in version 36, the intention is to - synchronise the sample period to the waveform so that the sample - will start on a rising edge or falling edge - -Applying -======== - -Let the children experiment with the internal microphone, try singing, -whistling, musical instruments, the Tam Tam musical Activity. The Turtle -Blocks Activity can generate an audio tone, see the Python Block. - -The children should learn through guided discovery that: - -- sound is a pressure wave -- the pitch of the sound is determined by the frequency or cycles per - second (Hz) -- the loudness of a sound is determined by the amplitude -- sounds contain multiple frequency components or harmonics -- the more pure sounds have less harmonics - -Sharing -======= - -This Activity does not support sharing. - -Extending -========= - -Measure is able to take input from a wide range of external sensors -including switches, photocells, temperature sensors, inductive loops, -hall effect sensors, soil probes and many more. - -Care should be taken not to exceed the allowable input voltage: - -> XO-1 -0.5 V to 5 V -> -> XO-1.5 -6 V to +9 V -> -> XO-1.75 -6 V to +9 V - -It is a good idea, particularly on the XO-1, to put a resistor of 680 -ohms in the phono plug, this increases the allowable input voltage -range. - -You can find ideas for fun science experiments at -[http://wiki.sugarlabs.org/go/Activities/TurtleArt/Using\_Turtle\_Art\_Sensors](http://wiki.sugarlabs.org/go/Activities/TurtleArt/Using_Turtle_Art_Sensors) -and -[http://wiki.laptop.org/go/Measure](http://wiki.laptop.org/go/Measure) |