unfortunately due to the wind I was able to do only a few tests ... on 150/200 meters. with a good video return signal. on returning home near the take-off I certainly encountered disturbances because I was with Tello behind the wifi repeater.
Today I finally got my Xiaomi wifi 2 range extender and finally got to fly my Tello up to 30m and ~100m away from me. Long story short, at some point the drone was too close to the grass and VPS failed and dragged it across tall (~20cm) dense grass field. I spent the next 2 hours searching for it and literally as I was ready to give up, I saw my Tello by my foot and I was happy to have lost just a rotor over the whole drone.
Now the question is for the future, I want to be able to find this drone when this happens again. I am thinking about attaching a small speaker to beep repeatedly as a "Find me" mod. I do have a spare 3.7V 220mAh battery that can be used for it.
What solutions do the others have so far? I want to weigh my options.