The localized LORAN is not that hard, IMO: Many TNs have GPS & Rbs. At least one simulator has been built. RF amps are easily available (ENI) for 100W pulse at 100 KHz. Home Depot has 250' rolls of #14 THHN.
FWIW, -John ============ > Poul, > > Please explain to me how spread spectrum would enhance any process of > frequency or > time recovery ? > > I just do not see it. > > The reason for the spread spectrum used with the GPS is because all of the > Birds > are in the same base frequency. Thus the spreading codes allow for > distinction > between the different signals. > > At 100 kHz the system bandwidth is very, very limited compared to the very > wide > spectrum of the GPS. Stepping up into the HF area brings in the sky wave > propagation issues. > > The whole purpose of suggesting an amateur approach is to utilize the > large base of > existing LORAN receivers as someone pointed out. However, as the number > of people > needing such a service is quite small it does not make economical sense, > as the > cost would certainly be prohibitive. The only feasible way would be to > have many > lower power 100 kHz transmitters and there are just not enough people > around to > construct, install and maintain such an operation; not to mention the > licensing > issues. > > Besides, you would achieve nothing above what is already provided by > operations > such as the 60 kHz WWVB and similar in other countries. So I see it as a > pie in > the sky nice idea but no cigar. > > Bill....WB6BNQ > > > Poul-Henning Kamp wrote: > >> In message <[email protected]>, >> "J. Fors >> ter" writes: >> >> >That's why I think an amateur timing LORAN network might be quite >> >feasable. Imagine a dozen 1 KW PEP A-LORAN stations with Rb and GPS >> >scattered around the US. There is no reason why a single transmitter >> could >> >not spoof a whole chain as it would not be used for navigation. >> >> Why try to emulate technology from WWII ? >> >> I would find it much more interesting to invent a good spread-spectrum >> modulation, and see if we could do world wide time-transmission with >> just a single 1W tranmistter per continent, which could be received >> with a simple down-converter frontend and a soundcard. >> >> Poul-Henning >> >> -- >> Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 >> [email protected] | 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 -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
