Re: [44net] Carrying 10 MHz reference clock over network ?

Interesting idea...  So I see three potential issues:Impedance, cat3-> cat6 cabling Impedance is 100 ohmsUnbalanced to balanced, coax is unbalanced, twisted pair is balanced. If you can convert from unbalanced to balanced it could work. If it is out of balance you'll have that reference signal radiating from the line.Topology, twisted pair is normally run in a star configuration, but that requires a Impedance matching hub in the middle.  You'll need to design and add that to drive multiple devices.I've never seen a cheap cat45 to f converter that actually had the right circuits to be clean. I used some for extending cctv signals and there was always ringing on the signal showing the 75 to 100 ohm and back mismatch. I worry that ringing might affect your oscillator lock accuracy. However, I bet if you built a active signal hub using op amps to drive the differential signal down the twisted pair you could get away with the single Impedance bump at the client device end. If you went with a more careful balun at the client devices that did a 2:1 Impedance adjustment it would be perfect.Good luck, it sounds like a fun project...73Bill Buhler - AF7SJSent from my Galaxy -------- Original message --------From: Toussaint OTTAVI via 44Net <44net(a)mailman.ampr.org> Date: 1/2/22 7:12 AM (GMT-07:00) To: AMPRNet working group <44net(a)mailman.ampr.org> Cc: Toussaint OTTAVI <t.ottavi(a)bc-109.com> Subject: [44net] Carrying 10 MHz reference clock over network ? Hi all,I'm thinking about building a GPS-disciplined 10 MHz reference oscillator. Of course, I'd like to add some networking features to it :-)NTP server is the most obvious, and is well documented.But I'd like to be able to carry 10 MHz reference signal to various locations in the shack over network cabling. My first idea is about using existing converters for TV/SAT :- RF to Ethernet passive couplers (a F connector tied to pins 1-2 of a RJ45 connector, $1 on Chinese warehouses). Will it work at 10 MHz ?Anyway, I do not have any idea about whether it will work or not while maintaining the reference/stability purpose of the 10 MHz signal.Any suggestions ?HNY & 73 de TK1BI_________________________________________44Net mailing list44Net@mailman.ampr.orghttps://mailman.ampr.org/mailman/listinfo/44net