With some care, you can see the tag replies with a 10eur rtl-sdr, but the rest if the software stack does not exist for free. CISC will sell you a license t

With some care, you can see the tag replies with a 10eur rtl-sdr, but the rest if the software stack does not exist for free. CISC will sell you a license to rent the software, but you need to provide your own rtl-sdr stick. Voyantic (now Impinj) has their own software that used an Airspy sdr, but it was end-of-lifed after Impinj bought them. And then for just cimparing tag performance, there is Voyantics Tagformance tester, but that's for comparing tag performance, not debugging something. But yeah, really annoying to see anything on a nornal swept spectrum analyzer.