PDP was frozen this morning, and we had to terminate the NX session and restart to get it back. Upon restart, PDP gave an "Error Turning RF", indicating it could not communicate with the R&S RF generator.
I went down and reboot the R&S and restarted PDP and everything is working again. The R&S displayed some error messages about corrupted memory in the EPROM, exactly as it did the last time this happeneed. Presumably the radiation from the Moller again caused the R&S to freak out.
Target operators should keep an eye on PDP, leaving it in Monitor, during a Moller. You may not see an error until you try to take data, though. Once a Moller is done, ask PDP for one point to ensure the R&S is working. Right now, an RF error requires an access.