----- Original Message ----- From: "Vitaliy" To: "Microcontroller discussion list - Public." Sent: Thursday, July 08, 2010 3:47 PM Subject: Re: [EE] Use of Zigbee modules for one way link? > Harold Hallikainen wrote: >>> The trick is that the antenna has to already be integrated into the >>> module so you get FCC cert without testing? >>> >>> You were looking for 915Mhz but the Microchip part is 2.4Ghz. >>> If frequency isn't important can you use something in the 433Mhz range >>> like a garage door opener without the encoder chip? >>> Since data is uni-directional how do you account for lost packets? >>> >>> thanks >>> chuckc >> >> That's correct, FCC modular transmitter certification requires an >> integrated antenna or approval with a specific antenna. As I recall, you >> are allowed to substitute another antenna of the same type with equal or >> less gain. >> >> I'm not really concerned about the frequency. The datarate is 10kbps. Data >> is transmitted repeatedly with CRC for error detection, so lost or >> erroneous packets are ignored. Looking around for FCC certified modular >> transmitters, they generally seem to Zigbee or WiFi transceivers. All the >> ones I've found also have the requirement that the antenna be 20cm away >> from people. A pure receiver would not have this limitation. So, that's >> why I'm asking about use of the Microchip Zigbee modules in a one way >> transmitter to many receivers configuration. > > Harold, why Zigbee? Why not one of Linx modules -- you don't want to > implement the protocol? Linx has a nice selection of RF modules, and http://www.rfdigital.com/?targetpage=item&filterpn=RFD21733 has some you might also want to consider. Regards, Bruce tech@rentron.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist