Currently trying to figure out what type of digital mode I'm listening to. I've purchased a Vaisala Radiosonde RS-92AM. It's a meteorological device usually attached to below a weather balloon. I've been trying to use SondeMonitor to decode what should be SGP encoded data (An example of what SGP sounds like). I've linked what I recorded from the device here which doesn't sound like SGP. I've done research on google but haven't found anything useful.

Actually, that does sound very much like the same kind of signal, but with a lot of noise on top of it.

What you recorded sounds like it was taken from an FM receiver with a very low signal strength, so there is a lot of white noise on the signal. With some low-pass filtering on the audio and some kind of white noise filtering, you could get it to sound a lot more like the one in the YouTube link.

  • Should've mentioned this in the OP, but I'm using an RTL-SDR with a rubber duck antenna. I'm also using the same settings seen within the YouTube video which is what really confused me. The RadioSonde TX and receiving antenna are located in the same room, if that makes any difference. Might just have to try a different antenna, though the one I have (came with my Yaesu VX-6R) shouldn't have an issue on 403MHz. – Josh Dec 8 '15 at 17:14

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