it has 40 miles line of sight, which is plenty for a high altitude balloon tracker, but it also costs almost $200 each, are there any matching receivers at a lower price? since I am only interested in having it transmit and not receive, I’d rather just pay more for a long range transmitter and a low cost receiver.
You’re going to need the same kind of XBee on both sides. This is because the modules not only transmit at certain frequencies, but also using a certain protocol to encode the 0s and 1s, and the receiver needs to know the protocol.
You might not need an XTend, though. If you’re that high in the air you’re going to get a LOT more range than on a ground-based system. The regular XBee 900 MHz (< $50) radios work, I believe, for the kinds of things you’re doing. I’m reasonably sure that we used a pair of the kind you linked to in the flights I participated in back in June, which flew to 94,000 feet and 40 miles downrange with no loss of contact with the ground.
it has 40 miles line of sight, which is plenty for a high altitude balloon tracker, but it also costs almost $200 each, are there any matching receivers at a lower price? since I am only interested in having it transmit and not receive, I’d rather just pay more for a long range transmitter and a low cost receiver.
I’m not sure what to look for when searching for the matching receiver, only that it needs to use Zigbee and 900mhz
All it needs to do is transmit GPS data
it’s all about choice of frequency, transmitter power, bandwidth, and antennas. High gain on the ground is of course more practical. We can do the math with some alternatives and get a high probability of what will work and what won’t.
Have you looked at these? http://lairdtech.stage.thomasnet-naviga … &forward=1 They are very easy to configure and use. For $200 you can get a development kit which contains 2 modules, 2 boards, and software.
mericas:
Have you looked at these? http://lairdtech.stage.thomasnet-naviga … &forward=1 They are very easy to configure and use. For $200 you can get a development kit which contains 2 modules, 2 boards, and software.
That gets you two radios, two antennas, two interface boards, two sets of wire, power supplies, etc. I was able to get a prototype up and running in a couple of hours using the development kit. AND I find the interface boards handy when I want to reprogram the radios.
I meant to say the digi modules/modems in general, they seem to be more plug and play. I could never get my AC4490 modules to work off the dev boards, then again I didn’t try that hard.
gussy:
I could never get my AC4490 modules to work off the dev boards, then again I didn’t try that hard.
I initially had problems with the module voltage. On the AC4490-1000 there are two voltage pins, VCC1 and VCC2. The documentation indicates that VCC1 can be 3.3 – 5.5V, ±50mV ripple. My experience is that only 3.3V works.