<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Phil,</div><div><br></div><div>Based on the datasheet, 4.7K is probably too high. I would go closer to 1K with that, 2K maximum. I am not sure at all how you arrived at 33 ohms, it would be a bad idea.</div><div><br></div><div>If you use the correct values and it still doesn't work, please consider that if you wired it wrong at any point, even for a split-second, it could have permanently damaged the part. But definitely do some testing before making that assumption.</div><div><br></div><div>--- Garrett</div><br><div><div>On Sep 22, 2013, at 9:22 PM, Phil Spitler <<a href="mailto:phil@bonfirelabs.com">phil@bonfirelabs.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hey list people, I have an electronics question that I wonder if somebody could help me with.<div><br></div><div><br></div><div>Basically I'm trying to build a high speed photography rig based on this.</div><div><br></div><div><a href="http://mattrichardson.com/blog/arduino-flash-trigger-parts-list/">http://mattrichardson.com/blog/arduino-flash-trigger-parts-list/</a></div><div><br></div><div>I have fallen at the first hurdle which is to get the opto-issolator to work.</div><div><br></div><div>I have a feeling it is due to the value of the resistor I'm using on the input.</div><div><br></div><div>I have followed his instructions but it seems like the resistor value of 4.7k might be too high.</div><div><br></div><div>I found the data sheet for the opto-issolator here <a href="http://pewa.panasonic.com/assets/pcsd/catalog/aqw-dip-2-form-a-catalog.pdf">http://pewa.panasonic.com/assets/pcsd/catalog/aqw-dip-2-form-a-catalog.pdf</a> </div><div><br></div><div>And more info here. <a href="http://www.digchip.com/datasheets/parts/datasheet/724/AQW280EH.php">http://www.digchip.com/datasheets/parts/datasheet/724/AQW280EH.php</a></div><div><br></div><div>I used an online resistor calculator <a href="http://led.linear1.org/1led.wiz">http://led.linear1.org/1led.wiz</a> and put in the numbers that I found in the data sheet (I think) and it gave me a resistor value of 33 ohms.</div><div><br></div><div>When I use the 4.7k resistor the opto-isolator doesn't do anything when the arduino pin goes high but I don;t want to use a much lower value in case I fuck the chip.</div><div><br></div><div>Any ideas?</div><div><br></div><div>Cheers.</div><div><br></div><div>Phil</div><div><br><div apple-content-edited="true"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; color: rgb(93, 16, 18); "><div style="font-size: medium; "><font face="Helvetica Neue"><font color="#536269"><b>Phil Spitler</b> | Creative Technologist | <b>Bonfire Labs</b> | t : 415.394.8200 m : 415.571.3139</font><br><font color="#536269"><br><a href="http://bonfirelabs.com/" style="color: rgb(83, 98, 105); text-decoration: none; ">Website</a> | <a href="http://www.facebook.com/bonfirelabs" style="color: rgb(83, 98, 105); text-decoration: none; ">Facebook</a> | <a href="http://www.linkedin.com/company/235257?trk=tyah" style="color: rgb(83, 98, 105); text-decoration: none; ">LinkedIn</a></font></font></div><div><font face="Helvetica Neue"><br></font></div></div><div><font class="Apple-style-span" color="#0019F1"><span class="Apple-style-span" style="text-decoration: underline; "><br></span></font></div></div></span><br class="Apple-interchange-newline"></div></span><br class="Apple-interchange-newline"></div><br class="Apple-interchange-newline"></div><br class="Apple-interchange-newline"></div><br class="Apple-interchange-newline"></div><br class="Apple-interchange-newline"><br class="Apple-interchange-newline"></div></div></div>_______________________________________________<br>Noisebridge-discuss mailing list<br><a href="mailto:Noisebridge-discuss@lists.noisebridge.net">Noisebridge-discuss@lists.noisebridge.net</a><br>https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss<br></blockquote></div><br></body></html>