One more item... Regarding measuring sunlight, there's a nice "calibrated" reference cell that's cheap which might work for general purposes. We decided to go with a photodiode that has a wide lens and narrow bandwidth and with some circuitry that lends stability and an output calibrated in W/m2.
The call is made by SolarWorld: http://solarworld.com/images/CalibratedCell.jpg They are provided with markings for the number of millivolts and microamps for 1 sun (1390W/m2). For this purpose, I think a better choice is a DS2438 which allows full range measurement and therefore takes full advantage of the A/D conversion resolution (or lack thereof). The 2438 is also more versatile with both a general purpose A/D input and a higher-resolution current sense differential measurement input. /m ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=103432&bid=230486&dat=121642 _______________________________________________ Owfs-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/owfs-developers
