If your concern is simply a stable frequency reference, that's true, even though I am not sure what kind of cleanup oscillator would match the short term stability of a maser. But also if you want to use it as a time standard, the phase shift in the fiber has to be compensated, and it's variations over temperature/humidity/gravity and whatnot must be accounted for.
This is time-nuts, we don't simply want to make things work, we want to make them work good :-) Didier > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] > Sent: Wednesday, November 26, 2008 2:50 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] 10 MHz over optical fiber? > > Hi Group; > It seems to me that the increase in noise introduced with an > optoelectronic device would not matter in most applications > if a cleanup oscillator is added. > > Best Wishes; > Thomas Knox > NIST > 4475 Whitney Place > Boulder Colorado 80305 > 1-303-554-0307 > [EMAIL PROTECTED] > > > > Quoting "Paul Boven" <[EMAIL PROTECTED]>: > > > Hi everyone, > > > > In message <[EMAIL PROTECTED]>, > Marco IK1ODO > > -2 > > writes: > >> Hi all, > >> > >> I have to carry a 10 MHz standard frequency signal inside an EMC > >> screened room via fiber optic cable. > >> > >> Not willing to re-invent the wheel, do something like an optical > >> standard frequency link exist on the market? > >> I think it is possible to use standard 100MB LAN transceivers, and > >> POF. Phase noise requirements are not very stringent, and the > >> distance is in the order of some tens of meters. > > > > I'm looking into something similar: transmitting an H-Maser signal > > (probably 10MHz) over some 34km using CWDM SFPs. At first > glance this > > seems fairly uncomplicated: get some SFPs, and SFP > connector + cage. > > Use a fast opamp/differential driver to drive the transmitting SFP, > > and use a similar setup at the other end to transform the received > > data back to 50 ohm unbalanced. How feasible would such a setup be? > > Possible problems might be that a 10MHz squarewave is > simply too 'slow' > > to be transmitted by an SFP, which expects 1.25Gb/s 8/10 > encoded data. > > Another interesting question would be how much jitter/noise such a > > setup would add? > > > > Regards, Paul Boven. > > > > _______________________________________________ > > 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. > > > > > _______________________________________________ > 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. > _______________________________________________ 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.
