Recent content by yo1dog

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    Multiple flowmeters read through mic port of an Android device

    Well, I got all my parts in and my circuit does not work. I discovered my flow meters change between an "on" and "off" state depending on the location of the wheel and do not send out a single pulse like I thought. When they are "on" +5v can be read from the pulse pin to the ground. When they...
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    Multiple flowmeters read through mic port of an Android device

    OK, did some more research and I think I need to implement a "voltage follower". I have updated my circuit to use an op-amp so I can control the voltage to the audio-in with the pulses from the flowmeters. http://www.digikey.com/schemeit/#1fwi Are there any specifications I should look for...
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    Multiple flowmeters read through mic port of an Android device

    Some more information: Here are the flowmermeters I have: http://www.adafruit.com/products/828 I used my multimeter and the current from the audio-in port is 5.15v and 2.17mA.
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    Multiple flowmeters read through mic port of an Android device

    I am attempting to read two hall-effect flowmeters through the audio-in (mic) port of an Android device. I want to be able to read both flowmeters independently. The audio-in port is a standard headset port so it only has one channel for the mic. So far I have been testing with my desktop PC. I...