Hi @hughhalf,
This is one of the exceptions where you expect the signal not to be in a straight line. This happens because the satellite is recently deployed and we don’t have accurate TLE. Specifically in this case, this satellite (with its 2 siblings that transmit on the same frequency) has been deployed yesterday from ISS and we use ISS TLE set for them, this is why you see this curve. So, if you check the history of the observation from the time that the satellite was deployed, you will be confident to vet it as having signal in waterfall.