<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">I used an audio jack breakout on an arduino proto shield with a simple RC circuit to level shift the AC.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">here is a <a href="https://drive.google.com/file/d/0B0lP-6BNGel_a09EbFBkeDJWamc/view?usp=sharing" target="_blank">photo</a>.  The proto shield is this one from  <a href="http://smile.amazon.com/SainSmart-Prototyping-Prototype-Breadboard-Arduino/dp/B0079WI2MK/ref=sr_1_4?ie=UTF8&qid=1421289842&sr=8-4&keywords=Prototype+Shield">sain smart </a> although there are many alternatives for this.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">The break out was from <a href="https://www.sparkfun.com/products/10588" target="_blank">sparkfun</a>  for which you need some <a href="https://www.sparkfun.com/products/116" target="_blank">headers </a>and the <a href="https://www.sparkfun.com/products/8032" target="_blank">jack</a>  maybe you can find one assembled </div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">There is also two resistors and a capacitor needed to get the AC signal into the ADCs input range.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">I really just copied the circuit from this <a href="http://www.instructables.com/id/Yun-based-Electricity-Monitor-with-Cloud-Support-T/?ALLSTEPS">intructable</a>. </div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">The instructable goes way further, using an Arduino Yun to make it readable via wifi, very cool, but maybe beyond what you want or need.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">Cheers,</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">​​</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><a href="/"></a><span id="goog_1223544077"></span><span id="goog_1223544078"></span><br></div><div class="gmail_extra"><div><div dir="ltr"><div><div dir="ltr"><div></div></div></div></div></div>
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