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LoRa 868Mhz Antenna Troubles

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Joules:
Cheers Ade, but it is the text communication I am after, Meshtastic being the initiator of this and then me going off on tangents playing with antenna's.

Example being, further development from the crap stubby to coupled coil stubby and now surgery......

To the stubby antenna that is...   I tested a PCB ultra wideband antenna and got better results than my modified stubby so figured I can do better. Cut up the stubby, unsolder the tiny helical they use and make a half wave dipole.  A small top hat drilled for the copper wire and larger hole inside to cover the pin and wire soldered together.  Turned from Acetal this is slide over the feed wire. Once in place I could fold that copper wire 90 degrees.  First test results on the NanoVNA proved disappointing with high SWR, it was then I rotated the wire to 90 degrees reference the ground plane.  This made a huge difference, again the NanoVNA allowed me to tune the angle just past 90 degrees.  Hot glue fixed everything in position and I could setup the antenna's I have for comparison testing.

I opted for the TinySA Ultra to compare the original stubby, then the UWB and finally my DIY  V dipole.  Screen shots of the results.  Not exactly rigorous scientific testing, but a comparison using the ESP32 board with a 1m patch lead on all antenna's.

The V dipole is a big advance over the stubby and my coil loaded version.  It was nice to have a "tiny" bit of machining for this.

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