Raw recording playback is way off the mark

Sub-GHz
#1

Hi everyone,

Got a remote that transmits @ 868.300 using 2FSK with 25kHz deviation.

If I record it with FZ in RAW mode using custom profile (see below) and then play it back, the playback doesn’t match. Here’s a waterfall for both - bottom is the original, top is the replay.

The custom profile is

Custom_preset_name: FSK25k
Custom_preset_module: CC1101
Custom_preset_data: 02 0D 0B 06 08 32 07 04 14 00 13 02 12 04 11 83 10 67 15 40 18 18 19 16 1D 91 1C 00 1B 07 20 FB 22 10 21 56 00 00 C0 00 00 00 00 00 00 00

which is the same as the one in the default firmware with DEVIATN reg (0x15) set to 0x40, which is 25.39 kHz.

Any ideas what’s going on here? Thanks!

CC @Astra, @SkorP

1 Like
Raw replay of dynamic code doesn't work (Hormann BiSecure)
#2

This looks like the Flipper is on the wrong frequency while recording. I think the Flipper only caught the strongest parts on the transmission. I’d say the frequency the Flipper is on while recording needs to be increased a little. Use the frequency analyzer on the Flipper to find the correct frequency. You can’t count on the remote being exactly where it says it is. Also try recording it at arms length from the transmitter if that doesn’t work.

1 Like
#3

Flipper is at 868.300. It’s in the custom profile, I just didn’t include that line.

Tried setting it to 868.290 just now and this did shift the playback downrange where it is supposed to be. Also, the waterfall of the playback looks about the same, so I’m guessing that it’s the playback freq that’s shifted, not the recording one.

Re: the frequency analyzer - I find it to be to crude to be useful. It keeps latching to a random harmonic and ends up cycling through the whole 868.249 to 868.349 range in 200 KHz increments.

#4

I was suggesting moving the Flipper frequency UP not down. Try taking a recording at 868.310 and 868.320.