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 <kb...@n1k.org> 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 <k8yumdoo...@gmail.com> 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) <james.schatz...@ac0xu.com> > > 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 -- time-nuts@lists.febo.com -- To unsubscribe > send > >> an email to time-nuts-le...@lists.febo.com > >> To unsubscribe, go to and follow the instructions there. > >> > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe > send an email to time-nuts-le...@lists.febo.com > > To unsubscribe, go to and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send > an email to time-nuts-le...@lists.febo.com > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.