Clint Like you I considered that and easy enough to do. But by that point you have built well over half the receiver. So I just said to heck with it and built the whole thing. The other issue is getting those pesky chips. There is one fellow time-nut that has a stash of CME chips he offered. Never heard that anyone accept me took him up on them. I built the regenerator with the cme and another with the 8160 chips just to insure they would both work for any time-nut that wanted to try. So by all means give it a shot isolate your new gain chain and use lots of limiting. The two I mention should deliver 50-70db worth. But the fact is the 3356 is at 50 db and the ad806 is no place close but sure puts out one nicely limited signal. I would believe simply a fet driving one of these chips would do the trick. Regards Paul.
On Fri, Nov 1, 2013 at 6:06 PM, Clint Turner <[email protected]> wrote: > When I was messing with my SkyScan WWVB clocks to determine if something > that WWVB's signal had done "broke" them, preventing them from setting > properly and so-doing, I wanted to see what the receiver module was seeing. > > (Spoiler: They didn't - they just break if the date is something later > than approx. August, 2012 - I mentioned this some months ago on this list, > providing a link to a blog entry where this was discussed in detail.) > > What I did to see what the clock chip was seeing via a 'scope was to hang > a JFET source follower on the "narrow" (downstream) side of the 60.003 kHz > bandpass filter crystal coupled with a small value cap and a with a 10 meg > resistor from the gate to ground: That didn't seem to adversely affect > performance, and I could see the phase flopping back and forth. (The > signal was pretty low - but usable.) > > At that point the AM was still present, so the "key up" portions of the > waveform were expectedly weaker - but it seemed to me at the time that I > could have used it for something more complicated down the line. > > What I was thinking at the time, were I to proceed farther, would have > been to take that buffered signal off-board, amplify it a bunch and then > run it through a limiter. In theory, this - along with the demodulated > time code - would have provided both the amplitude and phase components. > > Clint > KA7OEI > > > On Fri, 1 NOV 2013 saul swed said: > >> Hello to the group. It has been a while since I have sent anything. The >> last was the wwvb regenerator for time clocks. >> However I have been working on a general purpose wwvb receiver. One that >> is >> inexpensive, uses parts available today, is inexpensive, single supply, >> low >> power, and uses parts I don't need a microscope for. There are lots of >> older designs out there and at least one quite nice design is by one of >> our >> fellow time-nuts that started me thinking. But many of the designs use >> inductors that have become difficult to obtain. >> As much as I would have loved to hack one of the one chip wwvb clock chip >> wonders they simply did not work out. They are hot receivers actually >> because there was no way to pull the amplified wwvb signal out. Tried a >> number of schemes like 2 chips in parallel. One detecting the AM signal >> and >> providing AGC control to chip 2 that had no AGC or demod caps. >> > <snip> > > > ______________________________**_________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/** > mailman/listinfo/time-nuts<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.
