I have 2 xb24-z7sit-004(xbee series 2 I think) configured in at serial link mode-one coordinater one router. I am sending low rate serial data at 9600bps. this works fine but the range is terrible! About 10 feet indoors.
I have a laptop with an FTDI serial cable at each end to carry out testing.
I also can connect the router end to a battery powered TI Launchpad(arduino-like) board for further tests.
Each xbee has a Digi A24-hasm-450 aerial atached to its SMA connector.
I ran a link test in xctung. I'd send the scan graph but it seems I can't do attachments here. When the devices are about 4 feet apart the signal is about -68dBm. Double the distance and it goes to about -75dBm. Put the device about 10+ ft away and it drops to -89dBm. Any slight obstacle in the path
also causes further degredation. As a test I tried some old S1 modules
which were never very good at a distance, and got pretty much the same result.
I'm not a beginner at this sort of stuff and I have used other wireless systems from other manufacturers that have worked very well.
Maybe these xbees are just more susceptable to power/RF noise etc.
Any ideas how I can solve this?