Ecowitt WH51 europe version frequency

[CiccioDroid]

Hello everybody,
I have bought an ecowitt wh51 european version with 868mhz frequency, but if i set 868.3M 868.8M and 868.0M with sample rate of 250k i'm not receive any messages.
Do You have any suggestions?

[zuckschwerdt]

Try to find the signal first, see e.g. https://triq.org/rtl_433/ANALYZE.html#verify-a-transmission

[CiccioDroid]

Found 867.3M

[zuckschwerdt]

That seems rather far off, but your RTL-SDR might not report an accurate frequency.
Tune a little to the side, e.g. if the signal is at exactly 867.3M then use 867.35M or 867.4M

[gdt]

For what it's worth, my experience with Ecowitt transmitters is on 915 MHz (US). Actually measuring the frequency is difficult. However, I used 3 quality RTL-SDR dongles (SmarTEE v2, Smart v5, Blog v3) to look at a number of Ecowitt, Acurite, and TPMS transmitters. My conclusion was

• the 3 quality dongles were within 1 ppm or so of each other
• the Ecowitt stuff was very accurate in frequency, as was Ford TPMS
• the acurite stuff was close enough and with good dongles set to 433.92 worked fine
• two lesser dongles were off, by roughly 60 and 90 ppm. This is a vast amount at 868 or 915 Mhz

So @CiccioDroid cannot conclude that the transmitter is off until measuring a whole bunch of other stuff with the same dongle, and trying to calibrate. Doing this right is tricky, and even though I have radio experience, it took me several hours of thought.

So yes, by all means tune so you receive the signal. But look at the freq1/freq2 values, and make sure it's mid-band not at the edge. I find that freq1 is below tune and freq2 above for Ecowitt and that's been reliable.

If you have dongle that is not frequency stable, I recommend getting a Blog v3 or a Smart v4/v5.