Yeah, I think ours was less than 10 grams. As rules go, IIRC at least here in the Czech Republic anything below 100 g is unregulated, you just need to have a l

Yeah, I think ours was less than 10 grams. As rules go, IIRC at least here in the Czech Republic anything below 100 g is unregulated, you just need to have a licensed amateur radio operator, so that the probe can broadcast in the 20 meter WSPR band under his callsign.