RSSI values varied +/- 4 dB without touching anything. At home the results were analyzed from the datafile Node-Red creates. I left the tracker running for a few minutes to have a number of observations). I used 3 types of antenna’s: Small whip, large whip and collinear. My LoPy LoRa tracker was used as signal source. Later that day i did some more tests at 530m from my gateway and 7.2km from the gateway at Eindhoven airport (FFFEB827EB75534E). I used a N-connector pigtail cable (so the blue part is a little piece of RG174 coax). Tuned it a little more by cutting the top halve wave with a cm or so. Only after removing the complete quarterwave top end, the SWR got right. While measuring the SWR with a N1201SA antenna tester it was impossible to tune the SWR by cutting the whip. However, while building i didn’t put the bottom part together in the way it was planned. Realizing this could well end in a frustration (i did some collinears for ADSB with mixed results) i started off with what i thought was a proper design.
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