OP
Ole Petter Ronningen
Sat, Mar 27, 2021 11:08 AM
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an estimate
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right ballpark,
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality antenna
without seeing these effects, so I am fairly certain it is the antenna (or
my reference maser giving up the ghost..)
Thanks!
Ole
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an estimate
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right ballpark,
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality antenna
without seeing these effects, so I am fairly certain it is the antenna (or
my reference maser giving up the ghost..)
Thanks!
Ole
PK
Poul-Henning Kamp
Sat, Mar 27, 2021 11:31 AM
Ole Petter Ronningen writes:
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), [...]
My first suspect would be temperature-sensitivity of the antenna & preamp.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
--------
Ole Petter Ronningen writes:
> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
> on - it could be temperature sensitivity in the antenna (cheap patch
> jobbie), [...]
My first suspect would be temperature-sensitivity of the antenna & preamp.
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
DW
Dana Whitlow
Sat, Mar 27, 2021 1:03 PM
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen opronningen@gmail.com
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an estimate
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right ballpark,
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality antenna
without seeing these effects, so I am fairly certain it is the antenna (or
my reference maser giving up the ghost..)
Thanks!
Ole
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <opronningen@gmail.com>
wrote:
> Hi, All
>
> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
> on - it could be temperature sensitivity in the antenna (cheap patch
> jobbie), or I suspect my sealing of the outside connectors may not be
> watertight. I just wanted to ask the list of anyone know of/has an estimate
> of how much the propagation delay on an N and/or SMA can reasonably be
> expected to change in the presence of water? is 3 ns in the right ballpark,
> or would that effect be way bigger/smaller?
>
> Likewise, does anyone have reasonably accurate figures for how much
> temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
> Looking for some rough figures so I can look in the right direction..
>
> I've used the same gpsdo, cable and location with a high quality antenna
> without seeing these effects, so I am fairly certain it is the antenna (or
> my reference maser giving up the ghost..)
>
> Thanks!
> Ole
> _______________________________________________
> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
> an email to time-nuts-leave@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
>
OP
Ole Petter Rønningen
Sat, Mar 27, 2021 1:32 PM
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty clear 24 hour cycle, pointing to temperature as the culprit; but the preceeding 48 hours the phase shift did not follow a 24 hour period at all; the wheather has been all over the place, so it is hard to say.. More data needed! As always..
(of course, there is always a possibility that I’ve somehow bungled the data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main suspects; water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna so I can take the maser out of the equation.. (and reseal the connectors properly)
- mar. 2021 kl. 14:04 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen opronningen@gmail.com
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an estimate
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right ballpark,
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality antenna
without seeing these effects, so I am fairly certain it is the antenna (or
my reference maser giving up the ghost..)
Thanks!
Ole
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
an email to time-nuts-leave@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-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty clear 24 hour cycle, pointing to temperature as the culprit; but the preceeding 48 hours the phase shift did not follow a 24 hour period at all; the wheather has been all over the place, so it is hard to say.. More data needed! As always..
(of course, there is always a possibility that I’ve somehow bungled the data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main suspects; water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna so I can take the maser out of the equation.. (and reseal the connectors properly)
> 27. mar. 2021 kl. 14:04 skrev Dana Whitlow <k8yumdoober@gmail.com>:
>
> Ole,
>
> You did not mention whether this timing anomaly is periodic or steadily
> growing.
> That information could be of considerable diagnostic significance.
>
> Dana
>
>
>> On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <opronningen@gmail.com>
>> wrote:
>>
>> Hi, All
>>
>> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
>> on - it could be temperature sensitivity in the antenna (cheap patch
>> jobbie), or I suspect my sealing of the outside connectors may not be
>> watertight. I just wanted to ask the list of anyone know of/has an estimate
>> of how much the propagation delay on an N and/or SMA can reasonably be
>> expected to change in the presence of water? is 3 ns in the right ballpark,
>> or would that effect be way bigger/smaller?
>>
>> Likewise, does anyone have reasonably accurate figures for how much
>> temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
>> Looking for some rough figures so I can look in the right direction..
>>
>> I've used the same gpsdo, cable and location with a high quality antenna
>> without seeing these effects, so I am fairly certain it is the antenna (or
>> my reference maser giving up the ghost..)
>>
>> Thanks!
>> Ole
>> _______________________________________________
>> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
>> an email to time-nuts-leave@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-leave@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
BK
Bob kb8tq
Sat, Mar 27, 2021 2:21 PM
Hi
On most “stuff” a humidity to condensation issue shows up as an abrupt change.
Temperature hits a critical zone and the water comes out fairly quickly ( or dries off
fairly quickly). Net result is that the curve is not as smooth as a normal temperature
curve.
Bob
On Mar 27, 2021, at 9:32 AM, Ole Petter Rønningen opronningen@gmail.com wrote:
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty clear 24 hour cycle, pointing to temperature as the culprit; but the preceeding 48 hours the phase shift did not follow a 24 hour period at all; the wheather has been all over the place, so it is hard to say.. More data needed! As always..
(of course, there is always a possibility that I’ve somehow bungled the data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main suspects; water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna so I can take the maser out of the equation.. (and reseal the connectors properly)
- mar. 2021 kl. 14:04 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen opronningen@gmail.com
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an estimate
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right ballpark,
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality antenna
without seeing these effects, so I am fairly certain it is the antenna (or
my reference maser giving up the ghost..)
Thanks!
Ole
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
an email to time-nuts-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
Hi
On most “stuff” a humidity to condensation issue shows up as an abrupt change.
Temperature hits a critical zone and the water comes out fairly quickly ( or dries off
fairly quickly). Net result is that the curve is not as smooth as a normal temperature
curve.
Bob
> On Mar 27, 2021, at 9:32 AM, Ole Petter Rønningen <opronningen@gmail.com> wrote:
>
> Hi, Dana
>
> Thats the peculiar thing - these last 48 hors theres been a pretty clear 24 hour cycle, pointing to temperature as the culprit; but the preceeding 48 hours the phase shift did not follow a 24 hour period at all; the wheather has been all over the place, so it is hard to say.. More data needed! As always..
>
> (of course, there is always a possibility that I’ve somehow bungled the data, and the period has been 24 hours all along)
>
> This is why I am looking for ballpark figures for the two main suspects; water and temperature.
>
> I guess I should bite the bullet and rig up a second receiver/antenna so I can take the maser out of the equation.. (and reseal the connectors properly)
>
>
>> 27. mar. 2021 kl. 14:04 skrev Dana Whitlow <k8yumdoober@gmail.com>:
>>
>> Ole,
>>
>> You did not mention whether this timing anomaly is periodic or steadily
>> growing.
>> That information could be of considerable diagnostic significance.
>>
>> Dana
>>
>>
>>> On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <opronningen@gmail.com>
>>> wrote:
>>>
>>> Hi, All
>>>
>>> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am working
>>> on - it could be temperature sensitivity in the antenna (cheap patch
>>> jobbie), or I suspect my sealing of the outside connectors may not be
>>> watertight. I just wanted to ask the list of anyone know of/has an estimate
>>> of how much the propagation delay on an N and/or SMA can reasonably be
>>> expected to change in the presence of water? is 3 ns in the right ballpark,
>>> or would that effect be way bigger/smaller?
>>>
>>> Likewise, does anyone have reasonably accurate figures for how much
>>> temperature could be expected to affect the delay of signals? 20 ps? 20 ns?
>>> Looking for some rough figures so I can look in the right direction..
>>>
>>> I've used the same gpsdo, cable and location with a high quality antenna
>>> without seeing these effects, so I am fairly certain it is the antenna (or
>>> my reference maser giving up the ghost..)
>>>
>>> Thanks!
>>> Ole
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
>>> an email to time-nuts-leave@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-leave@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-leave@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
DW
Dana Whitlow
Sat, Mar 27, 2021 3:51 PM
Ole,
If you can stand the suspense, a time error recording of a month or more
duration
would probably be pretty informative (and interesting for us to see).
And when you speak of the maser, is that an active hydrogen maser? If so,
you're
a lucky man (unless it's in the process of dying). But there should be
scads of
diagnostics being logged, which should be enough to enable making a fairly
good
confidence check on it.
Dana
On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen opronningen@gmail.com
wrote:
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty clear
24 hour cycle, pointing to temperature as the culprit; but the preceeding
48 hours the phase shift did not follow a 24 hour period at all; the
wheather has been all over the place, so it is hard to say.. More data
needed! As always..
(of course, there is always a possibility that I’ve somehow bungled the
data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main suspects;
water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna so I
can take the maser out of the equation.. (and reseal the connectors
properly)
- mar. 2021 kl. 14:04 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps? 20
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality antenna
without seeing these effects, so I am fairly certain it is the antenna
my reference maser giving up the ghost..)
Thanks!
Ole
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
To unsubscribe, go to and follow the instructions there.
Ole,
If you can stand the suspense, a time error recording of a month or more
duration
would probably be pretty informative (and interesting for us to see).
And when you speak of the maser, is that an active hydrogen maser? If so,
you're
a lucky man (unless it's in the process of dying). But there should be
scads of
diagnostics being logged, which should be enough to enable making a fairly
good
confidence check on it.
Dana
On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <opronningen@gmail.com>
wrote:
> Hi, Dana
>
> Thats the peculiar thing - these last 48 hors theres been a pretty clear
> 24 hour cycle, pointing to temperature as the culprit; but the preceeding
> 48 hours the phase shift did not follow a 24 hour period at all; the
> wheather has been all over the place, so it is hard to say.. More data
> needed! As always..
>
> (of course, there is always a possibility that I’ve somehow bungled the
> data, and the period has been 24 hours all along)
>
> This is why I am looking for ballpark figures for the two main suspects;
> water and temperature.
>
> I guess I should bite the bullet and rig up a second receiver/antenna so I
> can take the maser out of the equation.. (and reseal the connectors
> properly)
>
>
> > 27. mar. 2021 kl. 14:04 skrev Dana Whitlow <k8yumdoober@gmail.com>:
> >
> > Ole,
> >
> > You did not mention whether this timing anomaly is periodic or steadily
> > growing.
> > That information could be of considerable diagnostic significance.
> >
> > Dana
> >
> >
> >> On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
> opronningen@gmail.com>
> >> wrote:
> >>
> >> Hi, All
> >>
> >> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
> working
> >> on - it could be temperature sensitivity in the antenna (cheap patch
> >> jobbie), or I suspect my sealing of the outside connectors may not be
> >> watertight. I just wanted to ask the list of anyone know of/has an
> estimate
> >> of how much the propagation delay on an N and/or SMA can reasonably be
> >> expected to change in the presence of water? is 3 ns in the right
> ballpark,
> >> or would that effect be way bigger/smaller?
> >>
> >> Likewise, does anyone have reasonably accurate figures for how much
> >> temperature could be expected to affect the delay of signals? 20 ps? 20
> ns?
> >> Looking for some rough figures so I can look in the right direction..
> >>
> >> I've used the same gpsdo, cable and location with a high quality antenna
> >> without seeing these effects, so I am fairly certain it is the antenna
> (or
> >> my reference maser giving up the ghost..)
> >>
> >> Thanks!
> >> Ole
> >> _______________________________________________
> >> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
> send
> >> an email to time-nuts-leave@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-leave@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-leave@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
OP
Ole Petter Rønningen
Sat, Mar 27, 2021 4:21 PM
Active HM, yes - nothing in the logs that corresponds, except a .5 degC diurnal temperature change - which roughly coincides with the outdoor temp, so no help there..
This was meant as a quick-and-dirty check, so a months is not in the cards - but that second antenna/receiver is climbing on my list of priorities, in imminent danger of surpassing «doing nothing on the couch»! :)
- mar. 2021 kl. 16:52 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
If you can stand the suspense, a time error recording of a month or more
duration
would probably be pretty informative (and interesting for us to see).
And when you speak of the maser, is that an active hydrogen maser? If so,
you're
a lucky man (unless it's in the process of dying). But there should be
scads of
diagnostics being logged, which should be enough to enable making a fairly
good
confidence check on it.
Dana
On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen opronningen@gmail.com
wrote:
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty clear
24 hour cycle, pointing to temperature as the culprit; but the preceeding
48 hours the phase shift did not follow a 24 hour period at all; the
wheather has been all over the place, so it is hard to say.. More data
needed! As always..
(of course, there is always a possibility that I’ve somehow bungled the
data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main suspects;
water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna so I
can take the maser out of the equation.. (and reseal the connectors
properly)
- mar. 2021 kl. 14:04 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
opronningen@gmail.com>
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an
estimate
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right
ballpark,
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps? 20
ns?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality antenna
without seeing these effects, so I am fairly certain it is the antenna
(or
my reference maser giving up the ghost..)
Thanks!
Ole
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
send
an email to time-nuts-leave@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-leave@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-leave@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-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
Active HM, yes - nothing in the logs that corresponds, except a .5 degC diurnal temperature change - which roughly coincides with the outdoor temp, so no help there..
This was meant as a quick-and-dirty check, so a months is not in the cards - but that second antenna/receiver is climbing on my list of priorities, in imminent danger of surpassing «doing nothing on the couch»! :)
> 27. mar. 2021 kl. 16:52 skrev Dana Whitlow <k8yumdoober@gmail.com>:
>
> Ole,
>
> If you can stand the suspense, a time error recording of a month or more
> duration
> would probably be pretty informative (and interesting for us to see).
>
> And when you speak of the maser, is that an active hydrogen maser? If so,
> you're
> a lucky man (unless it's in the process of dying). But there should be
> scads of
> diagnostics being logged, which should be enough to enable making a fairly
> good
> confidence check on it.
>
> Dana
>
>
>> On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <opronningen@gmail.com>
>> wrote:
>>
>> Hi, Dana
>>
>> Thats the peculiar thing - these last 48 hors theres been a pretty clear
>> 24 hour cycle, pointing to temperature as the culprit; but the preceeding
>> 48 hours the phase shift did not follow a 24 hour period at all; the
>> wheather has been all over the place, so it is hard to say.. More data
>> needed! As always..
>>
>> (of course, there is always a possibility that I’ve somehow bungled the
>> data, and the period has been 24 hours all along)
>>
>> This is why I am looking for ballpark figures for the two main suspects;
>> water and temperature.
>>
>> I guess I should bite the bullet and rig up a second receiver/antenna so I
>> can take the maser out of the equation.. (and reseal the connectors
>> properly)
>>
>>
>>>> 27. mar. 2021 kl. 14:04 skrev Dana Whitlow <k8yumdoober@gmail.com>:
>>>
>>> Ole,
>>>
>>> You did not mention whether this timing anomaly is periodic or steadily
>>> growing.
>>> That information could be of considerable diagnostic significance.
>>>
>>> Dana
>>>
>>>
>>>> On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
>> opronningen@gmail.com>
>>>> wrote:
>>>>
>>>> Hi, All
>>>>
>>>> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
>> working
>>>> on - it could be temperature sensitivity in the antenna (cheap patch
>>>> jobbie), or I suspect my sealing of the outside connectors may not be
>>>> watertight. I just wanted to ask the list of anyone know of/has an
>> estimate
>>>> of how much the propagation delay on an N and/or SMA can reasonably be
>>>> expected to change in the presence of water? is 3 ns in the right
>> ballpark,
>>>> or would that effect be way bigger/smaller?
>>>>
>>>> Likewise, does anyone have reasonably accurate figures for how much
>>>> temperature could be expected to affect the delay of signals? 20 ps? 20
>> ns?
>>>> Looking for some rough figures so I can look in the right direction..
>>>>
>>>> I've used the same gpsdo, cable and location with a high quality antenna
>>>> without seeing these effects, so I am fairly certain it is the antenna
>> (or
>>>> my reference maser giving up the ghost..)
>>>>
>>>> Thanks!
>>>> Ole
>>>> _______________________________________________
>>>> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
>> send
>>>> an email to time-nuts-leave@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-leave@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-leave@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-leave@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
DW
Dana Whitlow
Sat, Mar 27, 2021 4:38 PM
My own belief is that almost everything can be blamed on GPS, but then much
if not
most is my own fault for using an indoor antenna only about 6 or 7 feet
above ground
level.
Except when excessive lightning activity is around, I run a
continuous setup comparing
10 MHz phase between a T'Bolt GPSDO and a Rb, showing I & Q waveforms on a
very
slow roll-mode 'scope display which shows the most recent 4 hours. It just
sits there
and runs, and I glance at it many times per day in passing. It gets very
messy much
of the time.
A month-long recording could net you quite a bit of couch time :-)
Dana
On Sat, Mar 27, 2021 at 11:21 AM Ole Petter Rønningen opronningen@gmail.com
wrote:
Active HM, yes - nothing in the logs that corresponds, except a .5 degC
diurnal temperature change - which roughly coincides with the outdoor temp,
so no help there..
This was meant as a quick-and-dirty check, so a months is not in the cards
- but that second antenna/receiver is climbing on my list of priorities, in
imminent danger of surpassing «doing nothing on the couch»! :)
- mar. 2021 kl. 16:52 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
If you can stand the suspense, a time error recording of a month or more
duration
would probably be pretty informative (and interesting for us to see).
And when you speak of the maser, is that an active hydrogen maser? If
you're
a lucky man (unless it's in the process of dying). But there should be
scads of
diagnostics being logged, which should be enough to enable making a
good
confidence check on it.
Dana
On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <
wrote:
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty clear
24 hour cycle, pointing to temperature as the culprit; but the
48 hours the phase shift did not follow a 24 hour period at all; the
wheather has been all over the place, so it is hard to say.. More data
needed! As always..
(of course, there is always a possibility that I’ve somehow bungled the
data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main suspects;
water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna
can take the maser out of the equation.. (and reseal the connectors
properly)
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality
without seeing these effects, so I am fairly certain it is the antenna
my reference maser giving up the ghost..)
Thanks!
Ole
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
To unsubscribe, go to and follow the instructions there.
To unsubscribe, go to and follow the instructions there.
My own belief is that almost everything can be blamed on GPS, but then much
if not
most is my own fault for using an indoor antenna only about 6 or 7 feet
above ground
level.
Except when excessive lightning activity is around, I run a
continuous setup comparing
10 MHz phase between a T'Bolt GPSDO and a Rb, showing I & Q waveforms on a
very
slow roll-mode 'scope display which shows the most recent 4 hours. It just
sits there
and runs, and I glance at it many times per day in passing. It gets very
messy much
of the time.
A month-long recording could net you quite a bit of couch time :-)
Dana
On Sat, Mar 27, 2021 at 11:21 AM Ole Petter Rønningen <opronningen@gmail.com>
wrote:
> Active HM, yes - nothing in the logs that corresponds, except a .5 degC
> diurnal temperature change - which roughly coincides with the outdoor temp,
> so no help there..
>
> This was meant as a quick-and-dirty check, so a months is not in the cards
> - but that second antenna/receiver is climbing on my list of priorities, in
> imminent danger of surpassing «doing nothing on the couch»! :)
>
> > 27. mar. 2021 kl. 16:52 skrev Dana Whitlow <k8yumdoober@gmail.com>:
> >
> > Ole,
> >
> > If you can stand the suspense, a time error recording of a month or more
> > duration
> > would probably be pretty informative (and interesting for us to see).
> >
> > And when you speak of the maser, is that an active hydrogen maser? If
> so,
> > you're
> > a lucky man (unless it's in the process of dying). But there should be
> > scads of
> > diagnostics being logged, which should be enough to enable making a
> fairly
> > good
> > confidence check on it.
> >
> > Dana
> >
> >
> >> On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <
> opronningen@gmail.com>
> >> wrote:
> >>
> >> Hi, Dana
> >>
> >> Thats the peculiar thing - these last 48 hors theres been a pretty clear
> >> 24 hour cycle, pointing to temperature as the culprit; but the
> preceeding
> >> 48 hours the phase shift did not follow a 24 hour period at all; the
> >> wheather has been all over the place, so it is hard to say.. More data
> >> needed! As always..
> >>
> >> (of course, there is always a possibility that I’ve somehow bungled the
> >> data, and the period has been 24 hours all along)
> >>
> >> This is why I am looking for ballpark figures for the two main suspects;
> >> water and temperature.
> >>
> >> I guess I should bite the bullet and rig up a second receiver/antenna
> so I
> >> can take the maser out of the equation.. (and reseal the connectors
> >> properly)
> >>
> >>
> >>>> 27. mar. 2021 kl. 14:04 skrev Dana Whitlow <k8yumdoober@gmail.com>:
> >>>
> >>> Ole,
> >>>
> >>> You did not mention whether this timing anomaly is periodic or steadily
> >>> growing.
> >>> That information could be of considerable diagnostic significance.
> >>>
> >>> Dana
> >>>
> >>>
> >>>> On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
> >> opronningen@gmail.com>
> >>>> wrote:
> >>>>
> >>>> Hi, All
> >>>>
> >>>> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
> >> working
> >>>> on - it could be temperature sensitivity in the antenna (cheap patch
> >>>> jobbie), or I suspect my sealing of the outside connectors may not be
> >>>> watertight. I just wanted to ask the list of anyone know of/has an
> >> estimate
> >>>> of how much the propagation delay on an N and/or SMA can reasonably be
> >>>> expected to change in the presence of water? is 3 ns in the right
> >> ballpark,
> >>>> or would that effect be way bigger/smaller?
> >>>>
> >>>> Likewise, does anyone have reasonably accurate figures for how much
> >>>> temperature could be expected to affect the delay of signals? 20 ps?
> 20
> >> ns?
> >>>> Looking for some rough figures so I can look in the right direction..
> >>>>
> >>>> I've used the same gpsdo, cable and location with a high quality
> antenna
> >>>> without seeing these effects, so I am fairly certain it is the antenna
> >> (or
> >>>> my reference maser giving up the ghost..)
> >>>>
> >>>> Thanks!
> >>>> Ole
> >>>> _______________________________________________
> >>>> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
> >> send
> >>>> an email to time-nuts-leave@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-leave@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-leave@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-leave@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-leave@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
OP
Ole Petter Rønningen
Sat, Mar 27, 2021 4:52 PM
Oh, no qustion that it would be interesting, but I’d hate to «tie up» the gear for a month on a low cost patch antenna, when I have a much better one temorarily taken down - basically I just wanted a quick check of how much worse things are on «low end gear» - somewhat predictably that only served to uncover more questions than it answered..
- mar. 2021 kl. 17:39 skrev Dana Whitlow k8yumdoober@gmail.com:
My own belief is that almost everything can be blamed on GPS, but then much
if not
most is my own fault for using an indoor antenna only about 6 or 7 feet
above ground
level.
Except when excessive lightning activity is around, I run a
continuous setup comparing
10 MHz phase between a T'Bolt GPSDO and a Rb, showing I & Q waveforms on a
very
slow roll-mode 'scope display which shows the most recent 4 hours. It just
sits there
and runs, and I glance at it many times per day in passing. It gets very
messy much
of the time.
A month-long recording could net you quite a bit of couch time :-)
Dana
On Sat, Mar 27, 2021 at 11:21 AM Ole Petter Rønningen opronningen@gmail.com
wrote:
Active HM, yes - nothing in the logs that corresponds, except a .5 degC
diurnal temperature change - which roughly coincides with the outdoor temp,
so no help there..
This was meant as a quick-and-dirty check, so a months is not in the cards
- but that second antenna/receiver is climbing on my list of priorities, in
imminent danger of surpassing «doing nothing on the couch»! :)
- mar. 2021 kl. 16:52 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
If you can stand the suspense, a time error recording of a month or more
duration
would probably be pretty informative (and interesting for us to see).
And when you speak of the maser, is that an active hydrogen maser? If
so,
you're
a lucky man (unless it's in the process of dying). But there should be
scads of
diagnostics being logged, which should be enough to enable making a
fairly
good
confidence check on it.
Dana
On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <
opronningen@gmail.com>
wrote:
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty clear
24 hour cycle, pointing to temperature as the culprit; but the
preceeding
48 hours the phase shift did not follow a 24 hour period at all; the
wheather has been all over the place, so it is hard to say.. More data
needed! As always..
(of course, there is always a possibility that I’ve somehow bungled the
data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main suspects;
water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna
so I
can take the maser out of the equation.. (and reseal the connectors
properly)
- mar. 2021 kl. 14:04 skrev Dana Whitlow k8yumdoober@gmail.com:
Ole,
You did not mention whether this timing anomaly is periodic or steadily
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
opronningen@gmail.com>
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
working
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not be
watertight. I just wanted to ask the list of anyone know of/has an
estimate
of how much the propagation delay on an N and/or SMA can reasonably be
expected to change in the presence of water? is 3 ns in the right
ballpark,
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps?
20
ns?
Looking for some rough figures so I can look in the right direction..
I've used the same gpsdo, cable and location with a high quality
antenna
without seeing these effects, so I am fairly certain it is the antenna
(or
my reference maser giving up the ghost..)
Thanks!
Ole
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
send
an email to time-nuts-leave@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-leave@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-leave@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-leave@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-leave@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-leave@lists.febo.com
To unsubscribe, go to and follow the instructions there.
Oh, no qustion that it would be interesting, but I’d hate to «tie up» the gear for a month on a low cost patch antenna, when I have a much better one temorarily taken down - basically I just wanted a quick check of how much worse things are on «low end gear» - somewhat predictably that only served to uncover more questions than it answered..
> 27. mar. 2021 kl. 17:39 skrev Dana Whitlow <k8yumdoober@gmail.com>:
>
> My own belief is that almost everything can be blamed on GPS, but then much
> if not
> most is my own fault for using an indoor antenna only about 6 or 7 feet
> above ground
> level.
>
> Except when excessive lightning activity is around, I run a
> continuous setup comparing
> 10 MHz phase between a T'Bolt GPSDO and a Rb, showing I & Q waveforms on a
> very
> slow roll-mode 'scope display which shows the most recent 4 hours. It just
> sits there
> and runs, and I glance at it many times per day in passing. It gets very
> messy much
> of the time.
>
> A month-long recording could net you quite a bit of couch time :-)
>
> Dana
>
>
>> On Sat, Mar 27, 2021 at 11:21 AM Ole Petter Rønningen <opronningen@gmail.com>
>> wrote:
>>
>> Active HM, yes - nothing in the logs that corresponds, except a .5 degC
>> diurnal temperature change - which roughly coincides with the outdoor temp,
>> so no help there..
>>
>> This was meant as a quick-and-dirty check, so a months is not in the cards
>> - but that second antenna/receiver is climbing on my list of priorities, in
>> imminent danger of surpassing «doing nothing on the couch»! :)
>>
>>>> 27. mar. 2021 kl. 16:52 skrev Dana Whitlow <k8yumdoober@gmail.com>:
>>>
>>> Ole,
>>>
>>> If you can stand the suspense, a time error recording of a month or more
>>> duration
>>> would probably be pretty informative (and interesting for us to see).
>>>
>>> And when you speak of the maser, is that an active hydrogen maser? If
>> so,
>>> you're
>>> a lucky man (unless it's in the process of dying). But there should be
>>> scads of
>>> diagnostics being logged, which should be enough to enable making a
>> fairly
>>> good
>>> confidence check on it.
>>>
>>> Dana
>>>
>>>
>>>> On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <
>> opronningen@gmail.com>
>>>> wrote:
>>>>
>>>> Hi, Dana
>>>>
>>>> Thats the peculiar thing - these last 48 hors theres been a pretty clear
>>>> 24 hour cycle, pointing to temperature as the culprit; but the
>> preceeding
>>>> 48 hours the phase shift did not follow a 24 hour period at all; the
>>>> wheather has been all over the place, so it is hard to say.. More data
>>>> needed! As always..
>>>>
>>>> (of course, there is always a possibility that I’ve somehow bungled the
>>>> data, and the period has been 24 hours all along)
>>>>
>>>> This is why I am looking for ballpark figures for the two main suspects;
>>>> water and temperature.
>>>>
>>>> I guess I should bite the bullet and rig up a second receiver/antenna
>> so I
>>>> can take the maser out of the equation.. (and reseal the connectors
>>>> properly)
>>>>
>>>>
>>>>>> 27. mar. 2021 kl. 14:04 skrev Dana Whitlow <k8yumdoober@gmail.com>:
>>>>>
>>>>> Ole,
>>>>>
>>>>> You did not mention whether this timing anomaly is periodic or steadily
>>>>> growing.
>>>>> That information could be of considerable diagnostic significance.
>>>>>
>>>>> Dana
>>>>>
>>>>>
>>>>>> On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
>>>> opronningen@gmail.com>
>>>>>> wrote:
>>>>>>
>>>>>> Hi, All
>>>>>>
>>>>>> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
>>>> working
>>>>>> on - it could be temperature sensitivity in the antenna (cheap patch
>>>>>> jobbie), or I suspect my sealing of the outside connectors may not be
>>>>>> watertight. I just wanted to ask the list of anyone know of/has an
>>>> estimate
>>>>>> of how much the propagation delay on an N and/or SMA can reasonably be
>>>>>> expected to change in the presence of water? is 3 ns in the right
>>>> ballpark,
>>>>>> or would that effect be way bigger/smaller?
>>>>>>
>>>>>> Likewise, does anyone have reasonably accurate figures for how much
>>>>>> temperature could be expected to affect the delay of signals? 20 ps?
>> 20
>>>> ns?
>>>>>> Looking for some rough figures so I can look in the right direction..
>>>>>>
>>>>>> I've used the same gpsdo, cable and location with a high quality
>> antenna
>>>>>> without seeing these effects, so I am fairly certain it is the antenna
>>>> (or
>>>>>> my reference maser giving up the ghost..)
>>>>>>
>>>>>> Thanks!
>>>>>> Ole
>>>>>> _______________________________________________
>>>>>> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
>>>> send
>>>>>> an email to time-nuts-leave@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-leave@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-leave@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-leave@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-leave@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-leave@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
DW
Dana Whitlow
Sat, Mar 27, 2021 5:27 PM
Ah, yes. The wonderful thing about our modern science (and the toys that
arise from it)
is that there is a bottomless treasure trove of interesting things to
investigate.
It occurred to me that one could expand a bit on Bob's point to include the
probable
variation of water's dielectric constant when it goes between liquid and
solid states.
I once had a big problem with a 2m repeater's transmission line wherein a
connector
near the bottom end "filled" with water. I think the amount was little
more than a ml,
but its effect was to bring the repeater to its knees. I unscrewed the
connector,
drained a few drops from it, dried it with a hanky, and all was back to
normal upon
reassembly. This should not be too surprising considering water's
dielectric constant
of around 80.
Good luck with your own investigations.
Dana
On Sat, Mar 27, 2021 at 11:53 AM Ole Petter Rønningen opronningen@gmail.com
wrote:
Oh, no qustion that it would be interesting, but I’d hate to «tie up» the
gear for a month on a low cost patch antenna, when I have a much better one
temorarily taken down - basically I just wanted a quick check of how much
worse things are on «low end gear» - somewhat predictably that only served
to uncover more questions than it answered..
- mar. 2021 kl. 17:39 skrev Dana Whitlow k8yumdoober@gmail.com:
My own belief is that almost everything can be blamed on GPS, but then
if not
most is my own fault for using an indoor antenna only about 6 or 7 feet
above ground
level.
Except when excessive lightning activity is around, I run a
continuous setup comparing
10 MHz phase between a T'Bolt GPSDO and a Rb, showing I & Q waveforms on
very
slow roll-mode 'scope display which shows the most recent 4 hours. It
sits there
and runs, and I glance at it many times per day in passing. It gets very
messy much
of the time.
A month-long recording could net you quite a bit of couch time :-)
Dana
On Sat, Mar 27, 2021 at 11:21 AM Ole Petter Rønningen <
wrote:
Active HM, yes - nothing in the logs that corresponds, except a .5 degC
diurnal temperature change - which roughly coincides with the outdoor
so no help there..
This was meant as a quick-and-dirty check, so a months is not in the
- but that second antenna/receiver is climbing on my list of
imminent danger of surpassing «doing nothing on the couch»! :)
Ole,
If you can stand the suspense, a time error recording of a month or
duration
would probably be pretty informative (and interesting for us to see).
And when you speak of the maser, is that an active hydrogen maser? If
you're
a lucky man (unless it's in the process of dying). But there should be
scads of
diagnostics being logged, which should be enough to enable making a
good
confidence check on it.
Dana
On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <
wrote:
Hi, Dana
Thats the peculiar thing - these last 48 hors theres been a pretty
24 hour cycle, pointing to temperature as the culprit; but the
48 hours the phase shift did not follow a 24 hour period at all; the
wheather has been all over the place, so it is hard to say.. More data
needed! As always..
(of course, there is always a possibility that I’ve somehow bungled
data, and the period has been 24 hours all along)
This is why I am looking for ballpark figures for the two main
water and temperature.
I guess I should bite the bullet and rig up a second receiver/antenna
can take the maser out of the equation.. (and reseal the connectors
properly)
Ole,
You did not mention whether this timing anomaly is periodic or
growing.
That information could be of considerable diagnostic significance.
Dana
On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
wrote:
Hi, All
I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
on - it could be temperature sensitivity in the antenna (cheap patch
jobbie), or I suspect my sealing of the outside connectors may not
watertight. I just wanted to ask the list of anyone know of/has an
of how much the propagation delay on an N and/or SMA can reasonably
expected to change in the presence of water? is 3 ns in the right
or would that effect be way bigger/smaller?
Likewise, does anyone have reasonably accurate figures for how much
temperature could be expected to affect the delay of signals? 20 ps?
Looking for some rough figures so I can look in the right
I've used the same gpsdo, cable and location with a high quality
without seeing these effects, so I am fairly certain it is the
To unsubscribe, go to and follow the instructions there.
To unsubscribe, go to and follow the instructions there.
To unsubscribe, go to and follow the instructions there.
Ah, yes. The wonderful thing about our modern science (and the toys that
arise from it)
is that there is a bottomless treasure trove of interesting things to
investigate.
It occurred to me that one could expand a bit on Bob's point to include the
probable
variation of water's dielectric constant when it goes between liquid and
solid states.
I once had a big problem with a 2m repeater's transmission line wherein a
connector
near the bottom end "filled" with water. I think the amount was little
more than a ml,
but its effect was to bring the repeater to its knees. I unscrewed the
connector,
drained a few drops from it, dried it with a hanky, and all was back to
normal upon
reassembly. This should not be too surprising considering water's
dielectric constant
of around 80.
Good luck with your own investigations.
Dana
On Sat, Mar 27, 2021 at 11:53 AM Ole Petter Rønningen <opronningen@gmail.com>
wrote:
> Oh, no qustion that it would be interesting, but I’d hate to «tie up» the
> gear for a month on a low cost patch antenna, when I have a much better one
> temorarily taken down - basically I just wanted a quick check of how much
> worse things are on «low end gear» - somewhat predictably that only served
> to uncover more questions than it answered..
>
> > 27. mar. 2021 kl. 17:39 skrev Dana Whitlow <k8yumdoober@gmail.com>:
> >
> > My own belief is that almost everything can be blamed on GPS, but then
> much
> > if not
> > most is my own fault for using an indoor antenna only about 6 or 7 feet
> > above ground
> > level.
> >
> > Except when excessive lightning activity is around, I run a
> > continuous setup comparing
> > 10 MHz phase between a T'Bolt GPSDO and a Rb, showing I & Q waveforms on
> a
> > very
> > slow roll-mode 'scope display which shows the most recent 4 hours. It
> just
> > sits there
> > and runs, and I glance at it many times per day in passing. It gets very
> > messy much
> > of the time.
> >
> > A month-long recording could net you quite a bit of couch time :-)
> >
> > Dana
> >
> >
> >> On Sat, Mar 27, 2021 at 11:21 AM Ole Petter Rønningen <
> opronningen@gmail.com>
> >> wrote:
> >>
> >> Active HM, yes - nothing in the logs that corresponds, except a .5 degC
> >> diurnal temperature change - which roughly coincides with the outdoor
> temp,
> >> so no help there..
> >>
> >> This was meant as a quick-and-dirty check, so a months is not in the
> cards
> >> - but that second antenna/receiver is climbing on my list of
> priorities, in
> >> imminent danger of surpassing «doing nothing on the couch»! :)
> >>
> >>>> 27. mar. 2021 kl. 16:52 skrev Dana Whitlow <k8yumdoober@gmail.com>:
> >>>
> >>> Ole,
> >>>
> >>> If you can stand the suspense, a time error recording of a month or
> more
> >>> duration
> >>> would probably be pretty informative (and interesting for us to see).
> >>>
> >>> And when you speak of the maser, is that an active hydrogen maser? If
> >> so,
> >>> you're
> >>> a lucky man (unless it's in the process of dying). But there should be
> >>> scads of
> >>> diagnostics being logged, which should be enough to enable making a
> >> fairly
> >>> good
> >>> confidence check on it.
> >>>
> >>> Dana
> >>>
> >>>
> >>>> On Sat, Mar 27, 2021 at 8:33 AM Ole Petter Rønningen <
> >> opronningen@gmail.com>
> >>>> wrote:
> >>>>
> >>>> Hi, Dana
> >>>>
> >>>> Thats the peculiar thing - these last 48 hors theres been a pretty
> clear
> >>>> 24 hour cycle, pointing to temperature as the culprit; but the
> >> preceeding
> >>>> 48 hours the phase shift did not follow a 24 hour period at all; the
> >>>> wheather has been all over the place, so it is hard to say.. More data
> >>>> needed! As always..
> >>>>
> >>>> (of course, there is always a possibility that I’ve somehow bungled
> the
> >>>> data, and the period has been 24 hours all along)
> >>>>
> >>>> This is why I am looking for ballpark figures for the two main
> suspects;
> >>>> water and temperature.
> >>>>
> >>>> I guess I should bite the bullet and rig up a second receiver/antenna
> >> so I
> >>>> can take the maser out of the equation.. (and reseal the connectors
> >>>> properly)
> >>>>
> >>>>
> >>>>>> 27. mar. 2021 kl. 14:04 skrev Dana Whitlow <k8yumdoober@gmail.com>:
> >>>>>
> >>>>> Ole,
> >>>>>
> >>>>> You did not mention whether this timing anomaly is periodic or
> steadily
> >>>>> growing.
> >>>>> That information could be of considerable diagnostic significance.
> >>>>>
> >>>>> Dana
> >>>>>
> >>>>>
> >>>>>> On Sat, Mar 27, 2021 at 6:08 AM Ole Petter Ronningen <
> >>>> opronningen@gmail.com>
> >>>>>> wrote:
> >>>>>>
> >>>>>> Hi, All
> >>>>>>
> >>>>>> I am trying to chase down a 2-3-4 ns/day "anomaly" in a gpsdo I am
> >>>> working
> >>>>>> on - it could be temperature sensitivity in the antenna (cheap patch
> >>>>>> jobbie), or I suspect my sealing of the outside connectors may not
> be
> >>>>>> watertight. I just wanted to ask the list of anyone know of/has an
> >>>> estimate
> >>>>>> of how much the propagation delay on an N and/or SMA can reasonably
> be
> >>>>>> expected to change in the presence of water? is 3 ns in the right
> >>>> ballpark,
> >>>>>> or would that effect be way bigger/smaller?
> >>>>>>
> >>>>>> Likewise, does anyone have reasonably accurate figures for how much
> >>>>>> temperature could be expected to affect the delay of signals? 20 ps?
> >> 20
> >>>> ns?
> >>>>>> Looking for some rough figures so I can look in the right
> direction..
> >>>>>>
> >>>>>> I've used the same gpsdo, cable and location with a high quality
> >> antenna
> >>>>>> without seeing these effects, so I am fairly certain it is the
> antenna
> >>>> (or
> >>>>>> my reference maser giving up the ghost..)
> >>>>>>
> >>>>>> Thanks!
> >>>>>> Ole
> >>>>>> _______________________________________________
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> >>>>>>
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