Re: [time-nuts] Absolute phase

Hello Arthur, Might be interesting to try the same experiment both with the two receivers on the same antenna and on the two different antennas. In an ideal world I'd expect the time output(s) to track as well either way, but it would be interesting to know how well this works out in practice.

Re: [time-nuts] Absolute phase

When I first powered them on together, they seemed to drift all over the place with regards to relative phase. For the past hour now, they are keeping around 7 degrees and sometimes dropping to around 4. I think that is pretty amazing given all the stuff between the source and final display.

Re: [time-nuts] Absolute phase

Hi As the “filter” (or control loop) in some GPSDO’s scales, it impacts the degree of “agreement” between the GPSDO’s. Not all GPSDO’s scale filters so not all exhibit the behavior. The HP / Symmetricom Z38xx units are one family that do this kind of scaling. As the scale moves longer

[time-nuts] Absolute phase

I have 2 antennas mounted on opposite ends of a roof and both of them feed commercial GPS DA/splitters and I can have as many as 10 receivers running at one time for testing. I have also used one of the high frequency type F TV passive splitters with one D.C. feed through and added 200-300 ohm

Re: [time-nuts] Absolute phase

, at 20:38, time-nuts-requ...@febo.com wrote: > From: Jerry Hancock <je...@hanler.com> > Subject: Re: [time-nuts] Absolute phase > > I figured, what the heck, and just used a BNC T and it’s working. ___ time-nuts mailing list --

Re: [time-nuts] Absolute phase

I agree. I disconnected it after wondering about the active antenna bias. > On Nov 17, 2017, at 12:35 PM, Magnus Danielson wrote: > > Can work, can go wrong. > > One should be careful and think it though. > > Cheers, > Magnus > > On 11/17/2017 09:25 PM, Jerry Hancock

Re: [time-nuts] Absolute phase

Can work, can go wrong. One should be careful and think it though. Cheers, Magnus On 11/17/2017 09:25 PM, Jerry Hancock wrote: I figured, what the heck, and just used a BNC T and it’s working. On Nov 17, 2017, at 12:20 PM, Magnus Danielson wrote: Hi, The reason I

Re: [time-nuts] Absolute phase

I figured, what the heck, and just used a BNC T and it’s working. > On Nov 17, 2017, at 12:20 PM, Magnus Danielson wrote: > > Hi, > > The reason I mention sharing antenna is that it takes out the difference that > is natural from having different antennas and the

Re: [time-nuts] Absolute phase

Hi, The reason I mention sharing antenna is that it takes out the difference that is natural from having different antennas and the difference in multipath. Sharing antenna has its own set of problems, so a suitable antenna splitter was assumed. Effectively you need to bypass DC to power

Re: [time-nuts] Absolute phase

Thanks, understand completely. You mention “sharing an antenna”. Is there a problem with connecting the same antenna to two units? I am referring to my REF0/REF1 pair. Thanks > On Nov 17, 2017, at 11:39 AM, Magnus Danielson > wrote: > > Hi, > > First of all,

Re: [time-nuts] Absolute phase

Hi, First of all, the receiver varies around some average phase. The average of two receivers may not be the same, even if sharing antenna. Their average can be offset from "absolute phase" because of offsets in the receiver, antenna cables and antenna. If you are not to careful, a GPSDO will

Re: [time-nuts] Absolute phase

Hi Most GPSDO’s use a divider to get straight from the 10 MHz to the PPS. There are some that derive both the PPS and the 10 MHz off a higher frequency, they are not common in the eBay world (yet). The divider is going to have a fixed delay based on it’s design. That might be 35 ns, it might

Re: [time-nuts] Absolute phase

On 11/17/17 11:05 AM, Jerry Hancock wrote: Granted I expect someone on this list to reply with something that makes me feel stupid, if you have two GPSDO units running side by side, should the phase delta on the 10Mhz output be zero (ideally)? Is there an absolute phase standard kept between

[time-nuts] Absolute phase

Granted I expect someone on this list to reply with something that makes me feel stupid, if you have two GPSDO units running side by side, should the phase delta on the 10Mhz output be zero (ideally)? Is there an absolute phase standard kept between GPSDO units as all it would take is one