Rtl sdr

1. Build https://github.com/merbanan/rtl_433/blob/master/docs/BUILDING.md
2. Install

Get Techem readings:

1. Install
2. https://github.com/merbanan/rtl_433/
3. https://github.com/xaelsouth/rtl-wmbus (make install)
4. https://github.com/weetmuts/wmbusmeters

wmbusmeters rtlwmbus