Today was a good day to ride slowly and with a de-tour back to home. Putting my TTN test node (with a 1/4 Lambda wire antenna on it) in my backpack and with a active TTN Mapper - Android app a coverage plot was forming.
It's good to see how concrete structures attenuate the signal between the node and the gateway.
Next time a TTN Mapper drive with a better ground-plane antenna mounted on the back of my bike.