Reposting Harold's post with tag and subject line. Bad day or bad email client ? :-). _____________ ---------- Forwarded message ---------- From: Harold Hallikainen Date: 9 July 2010 08:42 Subject: To: Pic List I need a one way RF link. I'm considering use of 915MHz, but I can not find any transmitters with FCC modular transmitter certifications (http://louise.hallikainen.org/FCC/FccRules/2010/15/212/ ). Section 3.1 of http://ww1.microchip.com/downloads/en/DeviceDoc/70329b.pdf states that the MRF24J40MA has certification as a modular transmitter. I COULD go Zigbee all the way, except that the "receivers" would generally need to transmit back to the "transmitter" where the data originates. Section 3.1.1 of the datasheet requires the antenna be 20cm or more away from people. This disallows a handheld or portable "receiver." So, what about the possibility of operating one MRF24J40MA as a transmitter and multiple MRF24J40MA modules as receivers where the receivers NEVER transmit? Has anyone tried anything like this? Is it a good or bad idea? THANKS! Harold -- FCC Rules Updated Daily at http://www.hallikainen.com - Advertising opportunities available! -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist