Go Down

Topic: Which Xbee??? (Read 848 times) previous topic - next topic

atmega-ist

Hello, all -

I've been looking at the Xbee brochures for some time and I wanted to run my situation by those with more experience to make sure I'm on the right track.

I've got a 2.4Ghz RC plane and am interested in putting things like a battery meter, camera (still), etc. in the plane with some type of wireless platform to transmit data in (at least close to) real time.

I see that the XBee-Pro ZB has a 2-mile range (under the MOST optimal LOS conditions, I'm sure - but a good spec noetheless) and is on a through-hole PBC.  The antenna configuration seems perfect as well as it will accommodate the ground clearance.

This all sounds fine and dandy on paper but I wanted to make sure there wasn't more to it than that.  Should I be concerned about having two 2,4Ghz systems so close?  I'm not a professional in the wireless area but I understand that because it's digital it doesn't matter (to an extent) as both systems will have a sort of identifier for all transmissions.  Also, I know that electric motors have a tendency to make some pretty weird things happen to the electronics around them with all of the magnetism and current.  Obviously this is no issue for the plane's receiver but I'm wondering if that's just because the system is made to accommodate the proximity to the motor or if it's simply not an issue?

Lastly - let's say I have my Duemilanove and a bootloaded (word?) atmega328 with the proper cyrstal, caps, power system, etc.  Is there any additional hardware I'll need to create the network other than the XBees?

Thanks a lot!

PaulS

Quote
I see that the XBee-Pro ZB has a 2-mile range (under the MOST optimal LOS conditions, I'm sure - but a good spec noetheless) and is on a through-hole PBC.

Do you have a link to this XBee with through hole PCB? Most XBees (all that I've ever seen) have a bunch of pins with non-standard spacing (at least non-breadboard standard) and no through holes.

Quote
Obviously this is no issue for the plane's receiver but I'm wondering if that's just because the system is made to accommodate the proximity to the motor or if it's simply not an issue?

If the motors do not affect the receiver, it is not because the receiver is immune to noise. It is because the motors have capacitors to absorb the noise.

atmega-ist

PaulS -

Many thanks for the response.  The comparison chart to which I was referring can be found here: http://www.digi.com/pdf/chart_xbee_rf_features.pdf.  The unit I have in mind is the US/AU version of the XBee-Pro ZB.

Thanks for the tip about the capacitance.  I'll likely have the monitoring system on a separate power source (probably should've mentioned that before) so hopefully all should be well if the capacitance is the only issue.  My extremely limited understanding of the analog side of things had me concerned about some kind of electromagnetic field that would wreak havoc on all nearby systems/signals but then again I have been known to become overly concerned.

Thanks again for taking the time!

atmega-ist

Does anyone have experience with the xbee referred to in this PDF?

If anyone has any info on whether or not they think this would work for the aforementioned application I'd greatly appreciate it.

Thanks!

mrjonny2

Hi I am currently playing with the XBEE Pro ZB that you are talking about  You can get great range on the things as long as you use an external antennae.
For an RC plane I would recommend possibly mounting a U.Fl one under the fuselage under a plastic cover of some sort to get the best range, just make sure its sealed well to prevent fuel damage.


http://uk.farnell.com/pulse-engineering/w3525b100/antenna-pcb-2-4ghz-ipex/dp/1900064

atmega-ist

mrjonny2 -

Thank you so much for sharing your results!  I'm really glad you mentioned that about the antenna as well - I didn't know they were available with as much surface area as the one to which you've linked!  (It also prompted the search for "U.Fl"...  Haha - now I actually know what to call those things!)

Thanks again to all!

justjed


Quote
I see that the XBee-Pro ZB has a 2-mile range (under the MOST optimal LOS conditions, I'm sure - but a good spec noetheless) and is on a through-hole PBC.

Do you have a link to this XBee with through hole PCB? Most XBees (all that I've ever seen) have a bunch of pins with non-standard spacing (at least non-breadboard standard) and no through holes.


Indeed. If you look at the XB ZB Datasheet, it shows 2mm pin pitch on the pins. If you're going to etch your own PCB, well, no problem, I guess.

I haven't used the XBee. Just quickly looking around, I see that adapters for Arduino (or other microcontrollers) have several parts on them.
http://www.ladyada.net/make/xbee/index.html
http://www.arduino.cc/playground/Shields/Xbee01
http://www.ladyada.net/make/xbee/arduino.html

Or maybe you can do it more simply: http://answers.oreilly.com/topic/2458-how-to-connect-an-arduino-to-an-xbee-radio/ though that looks to be using a simpler XBee than the ZB Pro.
... it is poor civic hygiene to install technologies that could someday
facilitate a police state. -- Bruce Schneier

mrjonny2

Don't worry dude its my pleasure glad I could help

Go Up