HFU HF Underground
Technical Topics => SDR - Software Defined Radio => Topic started by: ChrisSmolinski on January 21, 2013, 2245 UTC
-
Every day, twice a day, over 800 weather balloons are launched around the world at exactly the same time. The data transmitted from these radiosondes is received by government agencies and shared with climatologists and meteorologist to develop climate models and predect the weather. Near [Carl]‘s native Auckland, a weather balloon is launched twice a day, and since they transmit at 403 MHz, he decided to use a USB TV tuner to receive data directly from an atmospheric probe. The hardware portion of this project consisted of building a high gain antenna designed for 162 MHz. Even though the radiosonde transmits at 403 MHz, [Carl] was easily able to receive on his out-of-band antenna. For the software, [Carl] used SDRSharp and SondeMonitor, allowing him to convert the coded transmissions from a weather balloon into pressure, temperature, humidity, and GPS data.
Full article: http://hackaday.com/2013/01/12/listening-in-on-weather-balloons-with-rtl-sdr/ (http://hackaday.com/2013/01/12/listening-in-on-weather-balloons-with-rtl-sdr/)
(Note - weather balloons here in the US use 1676, 1678, 1680, and 1682 MHz. I have tried, but have yet to hear one with an RTL dongle)
The article links to a youtube video as well:
[youtube]Mz2id1cBmjs[/youtube]
-
Oh, fun. Didn't know about this.
May have some hope here since the NWS has an office about 20 mi from my house. Plus a major university, int'l airport.
-
Hmm! MLB does too, may have to give this a try, thanks Chris!
-
This may not be much of an option for people in the eastern part of the country, but there are networks of seismic equipment out west that use UHF and VHF to communicate back to the mother ship. I haven't lived out there for many years, but there used to be a number of people who tried to monitor these devices, to try to get first hand data when an earthquake occurred.
I used to do a lot of hunting in the California desert back in the early 80s, and we would come across these weather balloons fairly frequently. Back then they were electro-mechanical; they had various electronic sensors for temperature, humidity, and so on, a radio transmitter (of course), and a multiplexor that consisted of a rotating arm that made contact with pads that connected to each sensor, feeding the data to the transmitter in sequence. I'm sure that they are now all-electronic, but these were quite ingenious and I'm sure they did the job just fine.
-
So that's what happened to the now extinct Mojave Jackrabbit.
-
They were all old, decrepit, and doomed to extinction anyway. Why they were still in existence is hard to say, but I certainly didn't have any qualms about putting them out of their misery.
So that's what happened to the now extinct Mojave Jackrabbit.
-
In the US receiving these signals generally requires some kind of directional antenna with a little gain even if you are not far from the launch point. That also means some kind of tracking mount. It is just not going to be as likely here as in areas using lower frequencies.
With that said, I have tried to receive these a few times, all to no avail thus far.
Ain’t nothing extinct about jack rabbits in the Mojave. Damn things are in my wife’s garden all the time. Youngest grandson and I just bagged him his first last weekend, in the El Paso Mountains.
T!