> John, > >> If a LORAN transmitter were destroyed by a terrorist team, a backup could >> be in operation in hours. A damaged GPS system could easily take many months or even years to fix. >> >> -John > > A LORAN site, with a several hundred meter high mast, a small house full of transmitter, signal generation and Cs clock(s?)... on a remote Norwegian island... would not be back online within a few hours after an attack.
I think it'd still be a lot easier to replace quickly than GPS jammers widely seeded. What would happen if some rogue country started building mini-GPS jammers and giving them to insurgents to randomly scatter around. A single donkey could carry many hundreds? Or suppose a jammer was built into a child's toy and ran intermittantly off the toy's batteries and sold by the zillions at Walmart for Christmas? > GPS is supposed to work without _any_ terrestrial support for days or weeks. I doubt that anyone can get something lethal for the SVs up in orbit without making it very obvious who they are. GPS now has lots of hot spare birds in orbit, that a instantly online with one or a few satellites going bust. I've never suggested attacking the birds is a credible terrorist threat. It is not, IMO. > That said, I think LORAN should be kept running as a backup, also with a firm commitment that it WILL KEEP running for 10+ years, giving vendors a reason to develop modern receivers. > > -- > > Björn IMO, GPS is much more vulnerable to a jamming attack and LORAN must be maintained as a backup. FWIW, -John ================ _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.