I was more interested in reducing the BW, rather than increasing it. Years ago, I bought up some of the resuidual of Appelco, a New Hampshire LORAN company that made units for Raytheon. Included were a bunch of active tunable filters, designed to "tune out" interference. However, there is no documentation.
I was just toying with the idea that a good shielded (possibly active) loop, the tunable filters, and an Austron 2100F might still be usable on the east coast. FWIW, -John ================ > In message <[email protected]>, "J. > Fors > ter" writes: > >>I remember reading somewhere that the envelope of the LORAN pulses was >>shaped to reduce the transmitted BW. > > The envelope is designed for two things: sensible BW and ease of > production. There is some math musing about it in the Radiation Lab > book. > >>Does anybody have a reference for that, and relatedly, what does the BW >> of >>the antenna have to be? Typically, loops are about 90 KHz to 110 KHz, but >>can that be narrowed down? > > In principle you can make it as narrow as you want, and compensate > for the resulting pulse-shape distortion in your receiver. > > Going much wider than 30kHz (85-115kHz) usually results in more > interference from CW signals than improvement to the loran signal. > > You can see a typical power spectrum at the bottom of this page: > > http://phk.freebsd.dk/loran-c/Antenna/ > > 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.
