SparkFun Forums

[sbonkosk]

One of my friends lives in an apartment complex and has a garage, however its attached to a separate building (Lets estimate around 500 ft). I want to build a garage door sensor, using Xbee's and a reed switch, that will let him know when the door has been opened/closed (it will communicate with another Xbee plugged into his computer and when it opens/closes, an app will trigger a tweet to be posted to Twitter so he can get alerted on his phone ). There are lots of obstructions between his apartment and garage.

Which Xbee could I use? Or is there another approach I could use? Thanks!

[stevech]

re "There are lots of obstructions between his apartment and garage."
you'll have to be specific on this - it's an RF world.

[sbonkosk]

re "There are lots of obstructions between his apartment and garage."
you'll have to be specific on this - it's an RF world.

Obstructions as in the building the garage is attached to and his building itself. I know the Xbee has good line of sight distance but I wasn't sure which one would work with so much concrete in the way, along with ~500ft.

[stevech]

Unlikely any of the 2.4GHz ones will work with this much non-line-of-sight at 500ft.

[sbonkosk]

Unlikely any of the 2.4GHz ones will work with this much non-line-of-sight at 500ft.

Yeah I was thinking that too. But what about the Xbee Pro 900? I see that it can have a range up to 15 miles, so I would think it would have enough juice to get through the concrete, right? I'm just not sure how different those are from the 2.4 Ghz versions. I wouldn't be using them with an Arduino, just the Xbee's themselves. Would I be able to use all the same breakout boards and stuff that the regular Xbee's have available? I need to be able to connect a reed switch to one and have the other plugged into the computer.

[JordanHusney]

If you want a quick design that will get this accomplished have a look at the open-source hardware XBee Pulse I/O board I made (http://jordan.husney.com/xbpio) for use in conjunction with the XBee Garage Door project (http://jordan.husney.com/xgd). If you can't get the range you need out of the 2.4GHz XBee ZB you can either drop in additional mesh routing repeating nodes or switch to 900MHz.


Jordan