How to make two XBEE adaptesr work with the XCTU range test

[Zot]

I have two XBEEs with adafruit adapter and I was trying to get the XCTU range test to work.

One of the XBEE running like a receiver and one like a transmitter from tweet-a-watt.

What do I need to do to the XBEEs to make the range test work? I have found some evidence that I need to tie RX to TX (creating a loopback), but I have not found any real details. How should I program the "other" xbee to get th range test.

BTW I really trying to figure our how to read signal strength. Is there a way to do this with normal packet deilvery?

[adafruit]

in the configure window look for DB "Received Signal Strength" thats probably what you want! just keep refreshing it by reading from the modem

[Zot]

Actually this was as easier done than said. I did not really need the X-CTU test, just the RSSI value

I looked in xbee.py and right there, line 39:

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self.rssi = p[3]

Which means it is part of the Xbee return (xb.rssi in wattcher), so I modified a debug line for my hack:

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print str(counter) +": RSSI: " + str(xb.rssi) + " | " + time.strftime("%Y %m %d, %H:%M")+ ", " + ": Voltage: " + str(CalcualtedVolts) + " avgv " + str(avgv) + " Thermistor: "  + str(x) + " Temperature: " + str(Temperature)

Which produces a line like this:

373: RSSI: 82 | 2009 04 26, 11:18, : Voltage: 1.80100585938 avgv 593 Thermistor: 71.2276559865 Temperature: 78.6813444881

You can also see this with processing, from Tom's Igoe's page: http://www.tigoe.net/pcomp/code/category/Processing/8. Though you will want to modify the packet length (at the top), as Processing complained about writing past the end of the packet buffer size. I believe you must be greater than 2 * expected packet length. Tom's code looks backwards for a previous packet which means if it misses the Ox7E packet indicator, it could run for while. Given that I am near the outer edge of measuring range, it can happen for a while. I set mine to 600 and it stopped giving me the "error, disabling serialEvent()" message.

Tom's code merely prints the latest setting, which is not all that useful for me. My debug line let's me track changes.

Using ideas from http://www.usbwifi.orconhosting.net.nz/ I have found that the Corner Cube measured a decrease in dB, though in practice did not seem to help connect a disconnected pair. The Vegatible Steamer actually was the best at aiming and reconnecting. USB Wifi's setup is much different from some other folks. The steamers have a stem in the middle which makes for easy xbee placement. A pho bowl with tin foil also see promising (though we just removed the tin foil later and held it in place).

I went to buy two steamers but then found that the cost of a steamer from the local supermarket was $10, and for the price of 2 steamers, I can get a more powerful Xbee. So I looked at a few more places and found that pretty deep strainer which has turned out even better. It was $7. I believe the deepness is important , since I am on the transmitting end of things, it reflects more of the signal (per the notes in http://www.usbwifi.orconhosting.net.nz/number13.jpg).

End results, is that with a vegetable steamer on one end (to be replaced) and a strainer on the other, I have signal about 20-30m, from an interior office, through 3-4 walls, out to the hot tub!

Pro tip: Remember to bring the strainer in if you want 1) Your spouse to stay, and/or 2) Want steamed vegetables later.

Personally I like the petal like appearance of the vegetable steamer.

[Zot]

Updated: I posted an http://www.instructables.com/id/Tweet-A ... structable

[adafruit]

hmm never thought about using a reflector!

[Zot]

Given a Point to Point link, reflectors (focusing antennas if you will) make great sense. Even in a multiple nodes, if you know that all of the nodes are "over there" a simple parabolic like the windurfer should do great things for range by merely reducing wasted transmissions to the wrong way, as well as focusing incoming radios waves.

I had really hoped that the corner cube would work better than it did. I've been fascinated with those since I learned we had a few on the moon. I think perhaps I need more thought on aiming it, or perhaps it better for receiving since it may not catch the spill over as well. It was cool to make one from a print out, a pizza box, and tin foil. Hardest part? Remembering to buy the tin foil.