I have spent hours searching the internet trying to find information on how to derive the manufacture date based on the unit serial number. I read it once some time ago and didn't write it down. I am sure someone out there knows how to read the serial number and can tell me. Since I just bought a used Motorola dsr922 off of Ebay I will be selling my 920 and wondered if you can read it the same way on a General Instrument reciever. So I guess I have 2 questions. Thanks so much for any information. I did find on Ebay that someone said it is the 7th digit in the serial number, is this true. That means mine was manufactured in 2004? (XXXX124XXXXXXXXX) I thought part of it indicated the month also.