The XBee 868 is similar to the XBee 900, but is legal to use in the UK, EU and other parts of the world where the 900MHz band is otherwise reserved.
See also, the blog XBee 900.
Another vendor on eBay was offering the XBee 868 development kit, DIGI INTERNATIONAL XBP08-DK DEVELOP KIT XBEEPRO 868MHz with 2 XBee-PRO for £120. However, I brought it to their attention that the Development boards were revision D (see XBee evaluation/development board blog for further details). They then sent the kit back to Digi, and received a replacement kit, with revision E boards. They then connected me to offer me first refusal for the kit at the same price as before.
However, after further investigation, I realised that the kits only come with one RPSMA (SIT) XBee, while the other has a whip (WIP) antenna. The contents of the kit, as listed on the Digi site, is as follows:
- (1) XBee-PRO 868 w/ RPSMA Connector
- (1) XBee-PRO 868 w/ Wire Whip antenna
- (2) USB Development Board
- (2) USB Cable
- (1) 868 MHz RPSMA Antenna
- (1) Power Adapter
- Various Adapters
I am looking for two RPSMA XBees (SIT), see XBee-PRO® 868 Long-Range RF Module for Europe. The reason being that I feel that two XBees, both with RP-SMA antennas, would have a longer range than one with an RP-SMA and one with a whip antenna. However, this is based upon my own supposition, as it is not easy to find a definitive guide.
In this thread, 868MHz antennas and range, on the Digi forums, the OP appears to suggest that with one of the XBees having just a whip antenna then the range is a lot less than the expected 40km, in fact approaching less than 1km (550m), in a wood. Another poster suggests 2.1km with direct line of sight (LOS), and 800m in an urban environment. Using a 15dB YAGI 1.2m antenna, 6.5km LOS was attained.
Another document, linked to in the above thread, XBee & XBee-PRO OEM RF Module Antenna Considerations, is nigh on useless w.r.t. the ranges available from a RP-SMA XBee when used in conjunction with another XBee with whip antenna.
This thread on the Arduino forums,
However, the Long Range 868 XBee devices appear to have reached their End-Of-Life:
- EOL in Progress – Product is not for new design. Please refer to XBee RF Modules for our latest products.
I then found that the XBee Pro 868 has been replaced by the newer XBee® 868LP Low-Power RF module for Europe.
These modules have a considerably lower range (8.4km max. compared to the quoted 40km for the Long Rangers). Also, it is not clear whether the original “Long Range” modules are compatible with the newer “Low Power” modules. From page 9 of the Digi XBee 865/868 LP RF Modules User Guide, it would appear that they are not. This may be due to the LPs being S8 (series 8) and the previous long range modules, XBee Pro 868MHz, being S5 (series 5).
Note The Digi XBee 865/868LP RF Modules are not compatible with other XBee products
It is worth noting here, that the 900 MHz “equivalents” of the 868 Long Range XBee Pro, namely the XBee -Pro 900HP and the XBee_Pro XSC are series S3B
For support of the Long Range modules, see XBEE-PRO 868 DEVELOPMENT KIT.
As an aside, this blog, How to bridge 40 km (or more) with two XBee-PRO 868 modules?, seems to suggest that it is possible to bridge to XBee networks (over 40km apart) using 868 XBee, using this library: Michael’s.Networking Toolkit. There is another article, DNS, Zigbee, XBee, Web, SMTP and POP classes in my MSchwarz Toolkit for .NET Micro Framework, here, by the same author. See also Microsoft .NET Framework ZigBee Library.