Hi Robert,
Really appreciated your Dragino “how to”.
I posted some info a while back - hopefully, you can use this for your video.
N.B. Assume any antenna gain figures are dBi - it is the more “correct” way to look at things (as it is relative to a point source). People’s default choice of antenna is usually a GPA or dipole, and this is why so many instinctively base their outlook on why dBd should be used. If you like ,it could be because people are so used to their “favorite” antenna already being incorporated in the system, so the following question is usually processed “How much better is this new antenna compared to my GPA / Dipole” rather than more correctly “compared to a point source”.
In the end - its mostly about placing an antenna up high and in free space.
1) Field strength DOES NOT vary inversely per the square of the distance. So may people get this wrong. I’ve tried to explain the maths in the links._
2) Why you shouldn’t use dBm to describe antenna gain