13/07/2015 - Design Analysis

A project log for Hackascilloscope

An all-in-one pocket oscilloscope, wave generator and ammeter that plugs into the headphone jack of your smart phone or tablet

Holly Wright • 07/16/2015 at 01:28•0 Comments

Attendance: Holly, Rob, Wilson, Tom and Lachlan

Tom brought an old phone so we took some measurements.

Holly’s Headphones	40 ohm on speaker, 17Mohm on mic
DC bias mic output	0V if mic detected, 0.8V if mic not detected
Mic detection	2V DC output on device plug in, if > 800 ohm is detected the phone will recognize the microphone, otherwise it will need to be removed and plugged in again.

We did some circuit development, talked about the current features and looked at ways of making them better. These were the results.

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07/16/2015 at 01:18 • 0 comments

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