Cynics Soapbox

Random thoughts...

SDR Pt.6

SDR Pt.6

It's been a while since I was able to devote much time to this and as the Weather Underground service is still not accepting submissions it hasn't been a high priority. However, with the festive season upon us and some time available I sat down to look at things again. The code I had written worked on my laptop but failed on the RaspberryPi :-( thinking about the differences between them an obvious line of investigation was the relative processing...

SDR Pt.5

SDR Pt.5

After the highs and low of the last coding session, it was heartwarming when after a few minor tweaks I saw this... Reading direct from the ISS :-)Now I had readings the next step was to start collecting them and then uploading to Weather Underground via their Personal Weather Station (PWS) network. My initial aim was to get a simple uploader working and then refine the data to slowly add the more complex items as time permits, but this...

SDR Pt.4

SDR Pt.4

I've managed to spend more time looking at it and have made some progress, though have once again run into issues. After much investigation I've created a processing flow that takes the raw samples and can extract valid weather packets -  but only from recorded files. When trying with live data it always returns invalid packets :-( The flow is this parse the samples into complex numbersdown mix these initial complex numbers using an appropriate frequency offsetpass the downmixed data...

SDR Pt.3

SDR Pt.3

Having found what appeared to be signals from the weather station in the data I captured (read here for more) the next logical step was to try and decode it. Inspectrum has some useful tools and following an example of analysing data I watched on YouTube, I started by adding a frequency plot (right click, Add derived plot > Add frequency plot). The center of the plot and the spectrum covered can be easily adjusted. Frequency plot centre and spread...

SDR Pt.2

SDR Pt.2

Continuing to try and figure out how to grab the data from the SDR it struck me I had  a few pieces of the puzzle to complete. Can I actually capture the data using the SDR? Until I know for sure that the data is available then doing anything else seems a little premature.If I can see the data, can I decode it and does it look as the information I have found on the web implies it should?...

SDR

SDR

For the last few years I’ve had a Davis Vantage Vue weather station. It’s been great though getting the data in a useful format is far from easy. Following our recent move the weather station needs to be relocated. It’s new home will be more exposed and as we’re still building the house there isn’t anywhere convenient to locate the large weather station base unit or associated pieces to upload the data. This has led...