Talk:Measure

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Revision as of 11:54, 17 September 2007 by MitchellNCharity (talk | contribs) (User feedback: moved a reply from Talk:MitchellNCharity.)
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quote

It is said "Give the child a hammer, and the world are his nails".

I need the source for this, I remember hearing it somewhere.--Arjs 12:11, 20 July 2007 (EDT)

line voltage

Never minding the fact that all round (non-USB) ports should tolerate line voltage, how might one make a safe connection? This is useful for showing line frequency and for showing the waveform. Waveforms from UPSes might be particularly interesting. Not being an EE, I can think of a few ideas: transformer, capacitor, resistor. Each of those can be done nicely, with proper electronic parts, or crudely with makeshift parts. 24.110.144.116 00:42, 1 August 2007 (EDT)


Measuring voltages outside 0.3V - 1.9V would require an external probe, the development of which is also in the pipeline.--Arjs 02:37, 15 August 2007 (EDT)

What about the reverse?

Measure turns the audio input into a generic input over a certain voltage range with essentially 0 current. Would it be possible to do the same for the audio output? This could run simple robotics, or allow switching between sensors. Obviously it would NOT be usable as a DC power source, just for switching transistors. Homunq 20:38, 7 August 2007 (EDT)


I have been thinking about that too. It would be interesting if I am able to achieve that. One of the other things that I have been thinking about is a simple generic USB based I/O interface. USB to Parallel chips aren't that expensive too...--Arjs 02:35, 15 August 2007 (EDT)

See Electrical output for further discussion of this and related possibilities...

Im guessing that it would be better to manage the USB ports, because the XO has three of this inputs/outputs, also there are thousands of electronics applications especially designed to USB user:RafaelOrtiz


The USBs although more versatile and flexible , would require us to mostly look at more and more external hardware. --Arjs 08:12, 17 September 2007 (EDT)

Maximum frequencies

hi Arjs where can i find the specs of measure..i.e maximum frequencies and stuff..?


The maximum sampling rate of the Ad188 sound chip is 48khz , which is the sampling rate I am using. I would say that maximum frequency would be about - 15Khz (slightly less than Fs/2). --Arjs 02:19, 15 August 2007 (EDT)

User feedback

  • When the activity first starts, it is taking audio as input. But talking, clapping, etc, may or may not create any visible change in the display. It might be nice if the default settings yielded some clean response to vocal input. To provide a positive very-first experience. Perhaps just show volume? If you can't whistle, it's not clear you can easily play with it. Build 581. MitchellNCharity 18:41, 15 September 2007 (EDT)
    (Moved from User talk:MitchellNCharity): Thanks for your feedback. Voice is hard to characterize (and hence display something concrete) - as it also contains harmonics and there is ambient noise etc. A whistle is relatively much cleaner source of frequency. However I do appreciate your idea and am trying to think how can I prevent a more intuitive first experience...please feel free to leave ideas on the discussion page.--Arjs 08:18, 17 September 2007 (EDT)