> I've uses more than 500 of them with internal oscilator > at 8MHz and doing 2400bps comunication without a problem. That's impressive on an RC clock - especially if they are used at both ends of the link. That's a good testimony to the stability of the RC clock. If you don't mind telling: - Do they talk to a PC or other device with a crystal controlled oscillator or to other units the same? - What temperature range are they used over? - Where are they used? (in an office / lab outdoors / industry etc). - Are they all from the same batch or from different batches? Russell McMahon -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads