Hi Anything you do that has a bunch of 10 MHz cables running out from here or there will impact your ability to listen to WWV at 10 MHz :) Other than killing all the sources, there is no silver bullet.
Bob > On Aug 28, 2021, at 7:57 PM, Dana Whitlow <[email protected]> wrote: > > Bob, my own motivation for going to fiber was entirely different. I > simply wanted to > run 10 MHz all over the place from reference sources in disparate > locations in the > house, and I quickly discovered that cable leakage was embarrassingly > severe. So > I shut down and began contemplating a fiber link. But then reality set in > and I realized > that running fiber across the house had its own big problems, so I set the > project aside. > > Dana > > > On Sat, Aug 28, 2021 at 3:32 PM Bob kb8tq <[email protected]> wrote: > >> Hi >> >> With a whole variety of pretty good OCXO’s going for cheap money >> on eBay, it’s likely less expensive to do cleanup oscillators on the link >> compared to going crazy with low noise optical this or that. Yes, you >> will be getting something in the high 150’s for noise, but still pretty >> good >> for $10. >> >> If you need better, spend $50 or so on a 10811. Still less money than >> some of the crazy fiber stuff. >> >> With either one, send over a high enough frequency that the loop isn’t >> dealing with reference spurs in any significant way. Given the clock rates >> Ethernet runs at these days, that part should be fairly straightforward. >> >> This *assumes* that there is a crossover somewhere practical between >> the fiber noise and the noise on the optical gear. You should be able to >> work out what it is with some fairly normal phase noise or ADEV testing. >> >> Bob >> >>> On Aug 28, 2021, at 3:03 PM, Dana Whitlow <[email protected]> wrote: >>> >>> I was looking for something similar about 18 months or so ago. Although >> I >>> haven't taken any >>> action yet, I concluded that one could do a nice job for under $200 per >>> segment, including the >>> transmitter and receiver modules and lots of connectorized multimode >>> fiber. What I *don't* know >>> is what the phase noise performance would be, except that I do know that >>> the fiber's VF *is* >>> materially influenced by temperature. >>> >>> I was looking primarily at the HFBR-2416 for the fiber receiver, and the >>> HFBR-1412 (standard >>> power) or the HFBR-1414 (high power option) for the transmitter Unlike >>> most of the available >>> models, these are fundamentally analog devices, meaning that you can >>> transmit sinewave >>> 10 MHz through them. At the time I was looking, Mouser was selling these >>> for about $20 each. >>> >>> See the datasheet at >>> >> https://www.mouser.com/datasheet/2/678/AV02-0176EN_2019-02-15-1827546.pdf >>> with particular attention to page 21 regarding the HFBR-2416 receiver. >>> >>> I was also looking at Fiber Instrument Sales for patch cords. We bought >> a >>> lot of fiber stuff from >>> them at Arecibo, and I was always happy with them. See: >>> >> https://www.fiberinstrumentsales.com/catalog-cable-assemblies?gclid=Cj0KCQjwvaeJBhCvARIsABgTDM7eNTkP2nQbyFzhcwDE38VnSEP879MBKV1ZyDq2YrnEtOn7_VfzjbkaAtpfEALw_wcB >>> >>> Somebody had pointed out yet another source of connectorized fibers >> ("patch >>> cords") to me, but I cannot find the name >>> at the moment. >>> >>> Dana K8YUM >>> >>> >>> On Sat, Aug 28, 2021 at 11:52 AM AC0XU (Jim) <[email protected]> >>> wrote: >>> >>>> I am hoping that you can help me about a couple of things: >>>> >>>> 1) My time-nuts summaries sometimes appear unformatted and unreadable. >> All >>>> the text from all the postings is crammed together without spacing. How >> can >>>> I fix it? >>>> >>>> 2) I want to distribute 10 MHz references by fiber. There are >>>> RF-over-Fiber products available, but too expensive for me (thousands of >>>> $$$ per xmit/rcv set). I am thinking that it should be possible to use >>>> fiber Ethernet components to do this. I don't mean IEEE 1588 but a much >>>> simpler, no-computer-required, solution. Possibly just converting sine >> wave >>>> (coax) to square wave (fiber) to sine wave (coax). I am looking for a >> low >>>> cost solution. Any thoughts or recommendations?? >>>> >>>> Thanks! >>>> >>>> Jim >>>> _______________________________________________ >>>> time-nuts mailing list -- [email protected] -- To unsubscribe >> send >>>> an email to [email protected] >>>> To unsubscribe, go to and follow the instructions there. >>>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] -- To unsubscribe >> send an email to [email protected] >>> To unsubscribe, go to and follow the instructions there. >> _______________________________________________ >> time-nuts mailing list -- [email protected] -- To unsubscribe send >> an email to [email protected] >> To unsubscribe, go to and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send an > email to [email protected] > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
