Hi Actually it’s pretty simple to track down that sort of jammer ….. and yes, the gear to do it is out there in quantity.
Bob > On Aug 30, 2018, at 6:51 PM, Scott McGrath <scmcgr...@gmail.com> wrote: > > As Brooke notes while low frequency jammers are possible, practicality is > another matter, All it takes to jam a city scale area is a box the size of > a pack of cigarettes. Because the GPS signal is very, very weak. > > As an intentional denial put a couple hundred on stray animals. Now track > those jammers down. > > I doubt if any agency owns enough DF equipment to find them all in a > reasonable amount of time. > > Thats why we need backup systems and each backup system will have less and > less accuracy as it increases in robustness. The HF systems could provide > adequate syncing for the Market example. > > > > On Aug 30, 2018, at 6:18 PM, Poul-Henning Kamp <p...@phk.freebsd.dk> wrote: > > -------- > In message <96e995c4-5ca2-af02-9738-0a6d87a9f...@pacific.net>, Brooke Clarke > writes: > >> But it's extremely hard to make a jammer for WWVB (60 kHz) [...] > > You can do it city-scale with a 18-wheeler sized loop-antenna > and a good size diesel-generator. > > However pedestrians will very likely note metalic items vibrating > as they pass the "mystery white truck". > > Sweden were much more serious about it: > > http://www.antus.org/RT02.html > > Tl;drs: > > They erected 9 200m tall Loran-C class antennas each driven by > a Loran-C transmitter with an advanced degree which could jam > Loran-C or Chayka. > > They even mounted decoy parabolas on the towers them to hide their > true purpose. > > The fact that all the transmitters were on the east coast does drop > a hint that swedens much touted neutrality had a bit of a slant. > > -- > Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 > p...@freebsd.org | TCP/IP since RFC 956 > FreeBSD committer | BSD since 4.3-tahoe > Never attribute to malice what can adequately be explained by incompetence. > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.