Sondehub Import Frequency rounding

[eben80]

Hi, I've enabled the Sondehub frequency import and it works. It looks however that it might need to round the frequency a bit. I guess this might be in issue with the frequency coming from Sondehub.

[LukePrior]

This is unrelated but we should make the default list of frequency/station/type combinations shorter so that there are more available positions for SondeHub by default.

[eben80]

There's not really a way to do this right? The frequency that is sent to Sondehub from auto_rx is a result of a scan which could have some drift.

[dl9rdz]

What currently is done already: If there is a qrg entry that is <=X away from a new entry from SondeHub, the new entry is ignored and if the qrg entry is not active, it is automatically activated. So what you can do: if you know possible but infrequently used frequencies you don't what to scan always, but activate when there is a report on SondeHub, put that as "inactive" in the qrg config.

What could be done additionally in the TTGO:

• Make X configurable (currently it is 3 kHz, maybe its a bit small)
• If some ID was already directly received by the TTGO, ignore new entries from SondeHub on a different frequency, independent of X
• Disable entries enabled as explained above after some time

Of course this will not remove that problem completely. I don't think much more can reasonably be done on the TTGO side. Some server side support could be feasible

• If a station frequently sends frequency reports with a large error, automatically send an email to that station's contact email politely asking to better calibrate the rtl-sdr
• If multiple ground stations are receiving the same sonde, return the median frequency instead of (or in addition to) the frequency reported by that last station seen. Theoretically the last thing could also be done on the client side by requesting all data for each specific sonde and then find the median frequency, but that is a lot of data and a lot of processing on the TTGO...

[eben80]

Thanks for that very thorough response. Yes I'm not getting the sonde decoded on the sondehub provided frequency even. So in the scenario from the screenshot, only the 400.6MHz had any output on the data page. As you would expect if the frequency IS actually 400.6

Too bad that the configured frequency is not being sent as part of telemetry 😄

I like your second approach on the TTGO but then, as you say, if the auto_rx frequency is out of calibration, I wouldn't be able to tune to the sonde on the frequency sent by sondehub anyway so I will close it on here. It seems the issue needs to be solved with auto_rx calibration.

[dl9rdz]

Too bad that the configured frequency is not being sent as part of telemetry 😄

It actually is sent for RS41 (not for others). No idea why some autorx stations are not sending the right frequency from decoded RS41 telemetry though....

[eben80]

Oh you're right, I missed this:

0x010: Frequency/Firmware

[eben80]

This looks promising: https://github.com/projecthorus/radiosonde_auto_rx/issues/577#issuecomment-951820562