How do I tell if my sub-1Ghz is working?

Sub-GHz
#1

I’m trying to capture a signal from my weather station.

  • I know it’s on 915mhz.
  • I know it’s transmitting: I can decode it using rtl433.

But even standing right underneath it, I don’t see:

  • The frequency caught in Frequency Analyzer
  • I would expect to see a spike in Read Raw RSSI when it transmits, but I don’t. (I picked FM238 modulation, as it is FSK).
  • I installed “Spectrum Analyzer”, and don’t see spikes in it either.

Maybe I’m holding it wrong…

I see some spikes around 300-320 Mhz in the spectrum analyzer, so maybe it’s doing something?

Any ideas on how I can easily tell if it’s working?

#2

Do you set Flipper to exact decimal digits? Are they from documentation or from RTL?

Different FSKs are out there. Flipper by default has two, and generally neither of them is guaranteed to be the correct one. Again, interrogate docs and/or RTL for full specification (bandwidth, deviation. etc.)

Unlikely. Small-range RF is highly ignorant of mechanics.

This was hard for me too. I ended up finding a simple doorbell that Flipper managed to hear, decode, and trigger on replay.

#3

What weather station is it?