Hi all For telemetry links I'm looking at a couple of frequencies. An almost suitable OTS product (reasonable price, needs to be imported) is 315MHz. I've always used discrete 433.92MHz Rx/Tx modules - inexpensive, but assembly needed to incorporate them into a design I see in the New Zealand Radio Spextrum Management's guide for unlicenced Short Range Devices http://www.rsm.govt.nz/cms/licensing/types-of-licence/telemetry-telecommand that 300 - 322MHz 10mW max 433.05 - 434.79MHz 25mW max Could I assume that the 434MHz band potentially has a greater range ? If eventual costs for a 315 (bought) or 434 (made) system turn out to be roughly similar, the greater range would be an advantage, as cost is secondary to performance TIA -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist