On Sat, Mar 29, 2008 at 9:44 AM, Apptech wrote: > I recently found that they are badly affected by the > proximity of an operating GSM cellphone. Their display goes > quietly mad running up and down and or sitting at random > values. Remove phone from area and all is well again. Range > of effect is up to about ?500 mm?. > That is why we are now doing radiated immunity testing up to 2.7GHz now. Next time maybe we need to increase this to even higher to deal with radiated emission. I believe the generic standard (IEC61000-4-3) calls for 80MHz to 1000MHz. But then we have now GSM1800 and GSM1900 (US) and Wifi/Bluetooth/etc now. We have a special walkie-talkie test as well because they can be very bad as well. Xiaofan -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist