The 2.4Ghz modules may be heading up to $36, but the cost of 900Mhz access will be going down in 2009. All the way down to $39 for a 900Mhz module which is upgraded to 115200 baud but range reduced to 1.8 miles.http://www.digi.com/products/wireless/zigbee-mesh/xbee-digimesh-900.jsphttp://www.digi.com/products/wireless/point-multipoint/xbee-pro-900.jspIt will be 5V tolerant on the UART pins, but you better keep those voltage dividers around until 2009. The $32 XBees are not 5V tolerant & quickly burned out if U followed the social network hits on Google that said they were.
Not as cheap as last year, but finally U North Americans have an affordable 900Mhz radio. Unfortunately, our income tax went up by over 4 XBee's so forget about seeing XBee PRO 900's on this blog.
Jack - I know it is already 2009, but I work for Digi and would be happy to return your call or email regarding XBee modules. Please feel free to email me at justin.ferguson@digi.com.
Wonder if anyone has succeeded in getting an XBee-Pro 900 out of digi.com before our predicted delivery date of 2009. They don't return phone calls & there's still no online ordering for it. It seems the 2.4Ghz band is too dangerous anywhere near Silicon Valley. 900Mhz is on the roadmap again.
Marty, the GPS L1 frequency is 1575.42 MHz, so it's closer to 900 MHz than 2.4 Ghz, but not by a whole lot. All electronic devices are going to emit some electromagnetic radiation. It's difficult to predict what is going to work. You might have problems either way, so you just have to deal with them.
I've seen a 1 watt 900 MHz radio work fine on a UAV system (these XBee Pros are 50 mW). I've seen a 1.4 GHz Pentium processor from an onboard computer cause interference with the GPS. The fix involved moving the GPS antenna aft and a bit of carbon fiber shielding.
P.S. I just got a confirmation email from Digi saying my stuff was shipped this morning.
Decided to forget about 900Mhz again. Ordering is going to be painful until 2009 & there's interference with GPS. U have to put a certain distance between the 900Mhz radios & GPS & that is a high risk item on a micro copter.
Based on anecdotes on the social networks & a chat, they're only selling XBee-Pro 900's by phone and the shipping is real expensive. Now we're all trying to support the product. No-one is giving away what that shipping figure is, but if you ordered a GPS module directly from uBlox, it was $50.
900Mhz benchmarking would be a trick, since the 115200 web page first appeared last week. His previous model did 9600 bps & has since been discontinued.
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$parky
Not as cheap as last year, but finally U North Americans have an affordable 900Mhz radio. Unfortunately, our income tax went up by over 4 XBee's so forget about seeing XBee PRO 900's on this blog.
Happy Hew Year!
I've seen a 1 watt 900 MHz radio work fine on a UAV system (these XBee Pros are 50 mW). I've seen a 1.4 GHz Pentium processor from an onboard computer cause interference with the GPS. The fix involved moving the GPS antenna aft and a bit of carbon fiber shielding.
P.S. I just got a confirmation email from Digi saying my stuff was shipped this morning.