[Tloewald]

I'd suggest something more sensible. E.g. one ping every Ns for the first 15 days, every 2Ns for the next 15 days, every 4Ns for the next 15 days... oh look, "infinite" duration.

However, I suspect the "pinger" mechanism is very, very simple and completely analog. No logic in its circuit at all. Because having it SURVIVE to ping 30d was the key consideration.