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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
For most signals (including analog AM and FM modes) you can use a laptop with an RTL-SDR USB dongle (fairly cheap), or another SDR, and a reasonably tuned antenna. Various RTL-SDR models can tune from around 500 kHz up to 1.75 GHz with 3 mhz of bandwdith, and works with free software like SDR# for Windows and GQRX for Linux. It works with lots of other software, too, for ham modes, digital modes, etc.
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