Tests, test, and again tests.

Critical task for today is communication LNA. Attempt to match antenna gives some promising results 0bDm (Bluetooth regular transmitted power) was stable communication over 1690m, second antenna was mismatched from 50om and lose was -3dBm but just one antenna match gives perfect result(1690m). LNA shows (instead of amplifying) lose around -6dB, but it is a progress: Sunday it was -20dB. Was made attempt to re-calculate impedance of a coaxial cable by measuring capacitance and inductance, it shows funny 33om instead of 50om. Also was made attempt to measure parameters of PCB, thickness varies from summer 2013 till today from 1.56 -> 1.47, Er calculated by capacitance of a microstrip (5pF) PCB shows range Er from 4.5 - 4.9, not so much difference from manufacturer (4.2-5.0 spec), it gives difference for microstrip from 81 to 85 Ohm. Recalculated Impedance assuming measured length of a cable and assumption of 33om – gives new parameters to try for today.

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