Its not just diurnal shift it plain old jumps anytime. Have been monitoring for periods from the eastcoast using both a Tracor 577 and 2 X HP vlf117 rcvrs. All kinds of stuff occur.
But then the older gents know all about that reality. Some may speak up. I like you want a second source but will say I was spoiled by loran. Maybe I did not realize how much. Even though my first loran timing recvr was homebrew in about 1989 as I recall. How far are you from wwvb?? On Mon, Oct 4, 2010 at 3:11 PM, Perry Sandeen <sandee...@yahoo.com> wrote: > > > Gents, > > Thanks for all the input on the HP 3586B and the Austron Loran C receiver. > I’ll try to distill what’s been said. > > It appears that using the HP 3586B for a WWVB receiver isn’t a good idea > unless I would use my HP 3336B or some other method to phase lock the BFO. > Since this seems to be way out of the KISS principle, I will go to plan B. > > I appreciate the clever circuit to convert the Austron to a phase detector > but the effort required to get just a phase detector alone isn’t cost > effective for me. > > Opening up the Austron shows that there is a great deal of space. If the > three Loran boards are gutted one of my Lucent Rubidium or Xtal standards > will just fit in their place. The power supply appears to be robust for the > power required. If not, there is space to add on. > > So to try to maximize the salvage of my purchase it looks like I should do > the following. > > 1. Gut the Loran boards and get a Lucent unit installed and working. > > 2. Build a big honkin’ quality 60 KHz loop antenna. I live in the country > so I can put up any size I can afford. > > 3. Convert the Austron RF amp boards to 60 KHz if I can get a schematic and > get lucky. Does anyone have one or know where I could download it? > > 4. If I don’t get lucky, build a TRF receiver in place of the Austron RF > boards. 60 KHz crystals are cheap from Mouser. Does anyone have experience > building a ladder or similar crystal filter? > > 5. After I get a good working 60 KHz signal, I‘ll divide it by six and > apply it to a Talbot 10 KHz phase detector. The Talbot circuit divides the > 10 MHz reference oscillator to 10KHz using 74HC390 decade dividers. It then > provides a correction circuit to the reference oscillator from its phase > detector. Since the Talbot circuit on uses about six IC’s it will fit > nicely in the rear chassis area. > > The goal, when completed, is to have a WWVB phase locked oscillator (yes I > have to figure out what to do about diurnal shift) a reference frequency > output and perhaps add a second Talbot phase detector circuit and meter for > calibrating other oscillators. > > Yes, the GPS is more accurate more quickly but the issue is to have a > second independent source for cross-checking. Though highly unlikely, GPS > satellites can be shot down, disabled or turned off or have their outputs > modified at any time. > > Comments? > > Regards, > > Perrier > > > > > > > _______________________________________________ > 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. _______________________________________________ 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.