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flipperdevices / flipperzero-firmware

Flipper Zero firmware source code
https://flipperzero.one
GNU General Public License v3.0
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Frequency Analyzer displays signal when there is none #1182

Closed ToddNutty closed 2 years ago

ToddNutty commented 2 years ago

Describe the bug After Flipper has scanned 315MHz Frequency Analyzer will display signal when there is none. Signal appears to range from 299.999 - 301.000 with RSSI often showing no to very low signal.

To Reproduce Steps to reproduce the behavior:

  1. Switch on...
  2. Enter Sub-GHz
  3. Use Read function
  4. Choose Config
  5. Set Frequency to: 315 / Hopping: OFF / Modulation: AM650
  6. Allow Flipper to scan for ~10 seconds
  7. Exit
  8. Open Frequency Analyzer
  9. Display should show 299.999 to ~301.000 (May need to physically move Flipper around)

Example screen capture: https://imgur.com/a/EjpFBg0

Expected behavior Frequency Analyzer should display all 0's (000.000) and only display greater values when signal is detected

Additional context The problem only seems to occur after using the Read function within Sub-GHz and scanning on the 315 frequency for a short time. II8YSN1 Version

Skorpionm commented 2 years ago

congratulations, next to you something very strong is broadcasting on this frequency. the frequency analyzer will still determine the key fobs, since they should be placed closer to the flipper. i can lower the RSSI detection level by this will lower the sensitivity

ToddNutty commented 2 years ago

congratulations, next to you something very strong is broadcasting on this frequency. the frequency analyzer will still determine the key fobs, since they should be placed closer to the flipper. i can lower the RSSI detection level by this will lower the sensitivity

I generally don't have issue with just restarting the Flipper, but what is interesting is I don't run into this issue unless I've previously tried scanning on 315Mhz on Read. I'll test at another location much further away to rule out local background noise.

jimilinuxguy commented 2 years ago

I wanted to tag on that I have seen this several times as well. Either the Frequency Analyzer will show a signal with 1-2 bars of RSSI or if you are recording, it will show actual graph/wave bars but its not real. I have checked with RTL-SDR and HackRF at the same time that I saw it. Restarting the device typically has made the error go away.

Astrrra commented 2 years ago

I have the same behavior in a basically radio-silent location

Skorpionm commented 2 years ago

I have an idea, I'll check it out tonight

Skorpionm commented 2 years ago

fix https://github.com/flipperdevices/flipperzero-firmware/pull/1192