[myself248]

Yes, a lot of GPS receivers provide RAIM or jamming indication, if they detect signals they're not expecting. Gpsjam just isn't set up to accept such data.

I think Galmon.eu may collect it along with all the other receiver-status data, but it isn't exposed in the main dashboard. You'd have to figure out how to extract it from the data, and I don't think anyone's done that yet, but we're in #galileo on OFTC IRC.

The main problem with this approach is that it's hyper-local. Ground stations aren't moving so they don't cover a very broad area, and they're not evenly distributed or even necessarily in interesting locations. Quite the contrary; regimes that employ GPS jamming are likely also hostile to citizens reporting on same.