PL
Paride Legovini
Mon, Jan 22, 2018 3:38 PM
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
As far as I can tell there are a few common options. One is the Trimble
Resolution T (or SMT), that should be good and proven. The major
annoyance is converting the 3.3V TTL serial logic-level to RS232, but
should be doable with a MAX3232 and a few capacitors.
Another option is this UBLOX LEA-5T:
https://www.ebay.it/itm/291769145465
The seller advertises an RS232 output pin, but I'm not sure it's
actually available, and I'd need at least lines, one for the NMEA
strings and one for the 1PPS signal. So, even if a RS232 TX pin is
actually there, it is probably not enough to build a good reference
clock, and I'd still need to convert some TTL levels to RS232...
Does anybody have experience with this receiver?
How does it compare to the Resolution T/SMT?
Another option is the Trimble Thunderbolt. This seems to do exactly what
I need, but it costs at least ten times more than the other modules.
Beside coming with a ready to use RS232 port and a nice case, does it
have other advantages?
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
As far as I can tell there are a few common options. One is the Trimble
Resolution T (or SMT), that should be good and proven. The major
annoyance is converting the 3.3V TTL serial logic-level to RS232, but
should be doable with a MAX3232 and a few capacitors.
Another option is this UBLOX LEA-5T:
https://www.ebay.it/itm/291769145465
The seller advertises an RS232 output pin, but I'm not sure it's
actually available, and I'd need at least lines, one for the NMEA
strings and one for the 1PPS signal. So, even if a RS232 TX pin is
actually there, it is probably not enough to build a good reference
clock, and I'd still need to convert some TTL levels to RS232...
Does anybody have experience with this receiver?
How does it compare to the Resolution T/SMT?
Another option is the Trimble Thunderbolt. This seems to do exactly what
I need, but it costs at least ten times more than the other modules.
Beside coming with a ready to use RS232 port and a nice case, does it
have other advantages?
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
E
ew
Mon, Jan 22, 2018 4:45 PM
Paride
The LEA-5T differs from other devices only that it has saw tooth information that can be used for correction or in a loop' I did a board and have one with variable delay using the 5T. Looking at the picture I do not even see an output for that information. Any later standard $10 module will be as good or better because he mentions 15 ns.
What do you need and please also look at what GPS is able to do without ionospheric correction
Bert
In a message dated 1/22/2018 11:07:52 AM Eastern Standard Time, time-nuts@febo.com writes:
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
As far as I can tell there are a few common options. One is the Trimble
Resolution T (or SMT), that should be good and proven. The major
annoyance is converting the 3.3V TTL serial logic-level to RS232, but
should be doable with a MAX3232 and a few capacitors.
Another option is this UBLOX LEA-5T:
https://www.ebay.it/itm/291769145465
The seller advertises an RS232 output pin, but I'm not sure it's
actually available, and I'd need at least lines, one for the NMEA
strings and one for the 1PPS signal. So, even if a RS232 TX pin is
actually there, it is probably not enough to build a good reference
clock, and I'd still need to convert some TTL levels to RS232...
Does anybody have experience with this receiver?
How does it compare to the Resolution T/SMT?
Another option is the Trimble Thunderbolt. This seems to do exactly what
I need, but it costs at least ten times more than the other modules.
Beside coming with a ready to use RS232 port and a nice case, does it
have other advantages?
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Paride
The LEA-5T differs from other devices only that it has saw tooth information that can be used for correction or in a loop' I did a board and have one with variable delay using the 5T. Looking at the picture I do not even see an output for that information. Any later standard $10 module will be as good or better because he mentions 15 ns.
What do you need and please also look at what GPS is able to do without ionospheric correction
Bert
In a message dated 1/22/2018 11:07:52 AM Eastern Standard Time, time-nuts@febo.com writes:
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
As far as I can tell there are a few common options. One is the Trimble
Resolution T (or SMT), that should be good and proven. The major
annoyance is converting the 3.3V TTL serial logic-level to RS232, but
should be doable with a MAX3232 and a few capacitors.
Another option is this UBLOX LEA-5T:
https://www.ebay.it/itm/291769145465
The seller advertises an RS232 output pin, but I'm not sure it's
actually available, and I'd need at least lines, one for the NMEA
strings and one for the 1PPS signal. So, even if a RS232 TX pin is
actually there, it is probably not enough to build a good reference
clock, and I'd still need to convert some TTL levels to RS232...
Does anybody have experience with this receiver?
How does it compare to the Resolution T/SMT?
Another option is the Trimble Thunderbolt. This seems to do exactly what
I need, but it costs at least ten times more than the other modules.
Beside coming with a ready to use RS232 port and a nice case, does it
have other advantages?
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
ST
Stephen Tompsett
Mon, Jan 22, 2018 4:55 PM
Why not consider a more recent current UBlox module?
e.g. the M8T https://www.u-blox.com/en/product/neolea-m8t-series
A quick internet search will find several suppliers of ready made
boards/modules...
On 22/01/2018 15:38, Paride Legovini via time-nuts wrote:
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
As far as I can tell there are a few common options. One is the Trimble
Resolution T (or SMT), that should be good and proven. The major
annoyance is converting the 3.3V TTL serial logic-level to RS232, but
should be doable with a MAX3232 and a few capacitors.
Another option is this UBLOX LEA-5T:
https://www.ebay.it/itm/291769145465
The seller advertises an RS232 output pin, but I'm not sure it's
actually available, and I'd need at least lines, one for the NMEA
strings and one for the 1PPS signal. So, even if a RS232 TX pin is
actually there, it is probably not enough to build a good reference
clock, and I'd still need to convert some TTL levels to RS232...
Does anybody have experience with this receiver?
How does it compare to the Resolution T/SMT?
Another option is the Trimble Thunderbolt. This seems to do exactly what
I need, but it costs at least ten times more than the other modules.
Beside coming with a ready to use RS232 port and a nice case, does it
have other advantages?
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Why not consider a more recent current UBlox module?
e.g. the M8T https://www.u-blox.com/en/product/neolea-m8t-series
A quick internet search will find several suppliers of ready made
boards/modules...
On 22/01/2018 15:38, Paride Legovini via time-nuts wrote:
> Dear fellow nuts,
>
> I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
> looking for a good and possibly affordable timing GPS receiver.
>
> As far as I can tell there are a few common options. One is the Trimble
> Resolution T (or SMT), that should be good and proven. The major
> annoyance is converting the 3.3V TTL serial logic-level to RS232, but
> should be doable with a MAX3232 and a few capacitors.
>
> Another option is this UBLOX LEA-5T:
>
> https://www.ebay.it/itm/291769145465
>
> The seller advertises an RS232 output pin, but I'm not sure it's
> actually available, and I'd need at least lines, one for the NMEA
> strings and one for the 1PPS signal. So, even if a RS232 TX pin is
> actually there, it is probably not enough to build a good reference
> clock, and I'd still need to convert some TTL levels to RS232...
>
> Does anybody have experience with this receiver?
> How does it compare to the Resolution T/SMT?
>
> Another option is the Trimble Thunderbolt. This seems to do exactly what
> I need, but it costs at least ten times more than the other modules.
> Beside coming with a ready to use RS232 port and a nice case, does it
> have other advantages?
>
> Am I overlooking something or missing interesting options?
>
> Cheers,
>
> Paride IZ3SUS
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
--
Stephen Tompsett
BK
Bob kb8tq
Mon, Jan 22, 2018 5:43 PM
Hi
It is doubtful that the pc board has an RS-232 to TTL converter onboard. The module it’s self
“talks” TTL levels rather than RS-232 levels. RS-232 to TTL adapters are dirt cheap and easy
to find on eBay. Make sure you get one that has control lines along with the basic RX and TX
functions. (You need to buffer the PPS signal). They also allow you to put in a “pulse stretcher”
on the PPS if the default is to short for your computer.
There is no value in a “timing” GPS vs a “normal” GPS for NTP. As long as you have a PPS output,
you are good to go. As noted elsewhere, something like the more modern M8 series is just
as cheap and will do a better job. Simply get any of the modules and an adapter. Hook them up
and move on. Total cost should come in < $30 delivered.
There are tons and tons of details on how do do all this in the archives.
Bob
On Jan 22, 2018, at 10:38 AM, Paride Legovini via time-nuts time-nuts@febo.com wrote:
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
As far as I can tell there are a few common options. One is the Trimble
Resolution T (or SMT), that should be good and proven. The major
annoyance is converting the 3.3V TTL serial logic-level to RS232, but
should be doable with a MAX3232 and a few capacitors.
Another option is this UBLOX LEA-5T:
https://www.ebay.it/itm/291769145465
The seller advertises an RS232 output pin, but I'm not sure it's
actually available, and I'd need at least lines, one for the NMEA
strings and one for the 1PPS signal. So, even if a RS232 TX pin is
actually there, it is probably not enough to build a good reference
clock, and I'd still need to convert some TTL levels to RS232...
Does anybody have experience with this receiver?
How does it compare to the Resolution T/SMT?
Another option is the Trimble Thunderbolt. This seems to do exactly what
I need, but it costs at least ten times more than the other modules.
Beside coming with a ready to use RS232 port and a nice case, does it
have other advantages?
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Hi
It is doubtful that the pc board has an RS-232 to TTL converter onboard. The module it’s self
“talks” TTL levels rather than RS-232 levels. RS-232 to TTL adapters are dirt cheap and easy
to find on eBay. Make sure you get one that has control lines along with the basic RX and TX
functions. (You need to buffer the PPS signal). They also allow you to put in a “pulse stretcher”
on the PPS if the default is to short for your computer.
There is no value in a “timing” GPS vs a “normal” GPS for NTP. As long as you have a PPS output,
you are good to go. As noted elsewhere, something like the more modern M8 series is just
as cheap and will do a better job. Simply get any of the modules and an adapter. Hook them up
and move on. Total cost should come in < $30 delivered.
There are tons and tons of details on how do do all this in the archives.
Bob
> On Jan 22, 2018, at 10:38 AM, Paride Legovini via time-nuts <time-nuts@febo.com> wrote:
>
> Dear fellow nuts,
>
> I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
> looking for a good and possibly affordable timing GPS receiver.
>
> As far as I can tell there are a few common options. One is the Trimble
> Resolution T (or SMT), that should be good and proven. The major
> annoyance is converting the 3.3V TTL serial logic-level to RS232, but
> should be doable with a MAX3232 and a few capacitors.
>
> Another option is this UBLOX LEA-5T:
>
> https://www.ebay.it/itm/291769145465
>
> The seller advertises an RS232 output pin, but I'm not sure it's
> actually available, and I'd need at least lines, one for the NMEA
> strings and one for the 1PPS signal. So, even if a RS232 TX pin is
> actually there, it is probably not enough to build a good reference
> clock, and I'd still need to convert some TTL levels to RS232...
>
> Does anybody have experience with this receiver?
> How does it compare to the Resolution T/SMT?
>
> Another option is the Trimble Thunderbolt. This seems to do exactly what
> I need, but it costs at least ten times more than the other modules.
> Beside coming with a ready to use RS232 port and a nice case, does it
> have other advantages?
>
> Am I overlooking something or missing interesting options?
>
> Cheers,
>
> Paride IZ3SUS
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
AK
Attila Kinali
Mon, Jan 22, 2018 6:18 PM
On Mon, 22 Jan 2018 16:38:01 +0100
Paride Legovini via time-nuts time-nuts@febo.com wrote:
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
As far as I can tell there are a few common options. One is the Trimble
Resolution T (or SMT), that should be good and proven. The major
annoyance is converting the 3.3V TTL serial logic-level to RS232, but
should be doable with a MAX3232 and a few capacitors.
Another option is this UBLOX LEA-5T:
https://www.ebay.it/itm/291769145465
The seller advertises an RS232 output pin, but I'm not sure it's
actually available, and I'd need at least lines, one for the NMEA
strings and one for the 1PPS signal. So, even if a RS232 TX pin is
actually there, it is probably not enough to build a good reference
clock, and I'd still need to convert some TTL levels to RS232...
Does anybody have experience with this receiver?
How does it compare to the Resolution T/SMT?
For raw GPS PPS output, your performance is limited by multi-path
and how much of the sky you see. If you have perfect conditions,
I expect both to perform at the same level. Under not so perfect
conditions, go for the LEA. I have here a Trimble UCCM and
Oscilloquartz Star4 GPSDO (using a LEA-5T). Compared to the Star4,
the UCCM is basically deaf. And mind you, the LEA-5 family came out
somewhen around 2006, ie is already a more than 10 year old design
and probably of the same age as the UCCM. The modern LEA's got a few
dB better yet.
For an NTP server, where you wont need anything better than 1µs
resolution, I think one of the many 10-bucks ublox LEA/NEO boards
that you can find on ebay are good enough (standard navigation
receivers give you better than 100ns accuracy). If you still want
to have a timing receiver, then go for one of the NEO-M8T, LEA-M8T or
LEA-6T based boards. Be aware that the NEO modules do not have the
circuit to provide power to the antenna, so it must be either
passive or you need an external bias-T. The LEA's can provide up
to 50mA (so no Zephyr!).
If you want to step up your game and get even better stability,
take one of the LEA based GPSDOs (like the Star4 mentioned above).
Attila Kinali
--
It is upon moral qualities that a society is ultimately founded. All
the prosperity and technological sophistication in the world is of no
use without that foundation.
-- Miss Matheson, The Diamond Age, Neil Stephenson
On Mon, 22 Jan 2018 16:38:01 +0100
Paride Legovini via time-nuts <time-nuts@febo.com> wrote:
> I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
> looking for a good and possibly affordable timing GPS receiver.
>
> As far as I can tell there are a few common options. One is the Trimble
> Resolution T (or SMT), that should be good and proven. The major
> annoyance is converting the 3.3V TTL serial logic-level to RS232, but
> should be doable with a MAX3232 and a few capacitors.
>
> Another option is this UBLOX LEA-5T:
>
> https://www.ebay.it/itm/291769145465
>
> The seller advertises an RS232 output pin, but I'm not sure it's
> actually available, and I'd need at least lines, one for the NMEA
> strings and one for the 1PPS signal. So, even if a RS232 TX pin is
> actually there, it is probably not enough to build a good reference
> clock, and I'd still need to convert some TTL levels to RS232...
>
> Does anybody have experience with this receiver?
> How does it compare to the Resolution T/SMT?
For raw GPS PPS output, your performance is limited by multi-path
and how much of the sky you see. If you have perfect conditions,
I expect both to perform at the same level. Under not so perfect
conditions, go for the LEA. I have here a Trimble UCCM and
Oscilloquartz Star4 GPSDO (using a LEA-5T). Compared to the Star4,
the UCCM is basically deaf. And mind you, the LEA-5 family came out
somewhen around 2006, ie is already a more than 10 year old design
and probably of the same age as the UCCM. The modern LEA's got a few
dB better yet.
For an NTP server, where you wont need anything better than 1µs
resolution, I think one of the many 10-bucks ublox LEA/NEO boards
that you can find on ebay are good enough (standard navigation
receivers give you better than 100ns accuracy). If you still want
to have a timing receiver, then go for one of the NEO-M8T, LEA-M8T or
LEA-6T based boards. Be aware that the NEO modules do not have the
circuit to provide power to the antenna, so it must be either
passive or you need an external bias-T. The LEA's can provide up
to 50mA (so no Zephyr!).
If you want to step up your game and get even better stability,
take one of the LEA based GPSDOs (like the Star4 mentioned above).
Attila Kinali
--
It is upon moral qualities that a society is ultimately founded. All
the prosperity and technological sophistication in the world is of no
use without that foundation.
-- Miss Matheson, The Diamond Age, Neil Stephenson
GE
Gary E. Miller
Mon, Jan 22, 2018 6:33 PM
Yo Paride!
On Mon, 22 Jan 2018 16:38:01 +0100
Paride Legovini via time-nuts time-nuts@febo.com wrote:
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
Before you bother looking at any GPS, you need to look at your server.
Hardly any Intel CPU can give you time resolution much better than
200 nS on a PPS in. Raspberry Pi's actually have slightly better
clock resolution than Intel parts, just under 190 nS.
That resolution os worse than what you get out of any good modern
GPS.
By 'local resolution' I mean the shortest time interval you can
read by repeatedly doing clock_systime() calls. clock_system() is
is many key ntpd paths.
The accuracy of your NTP server will be strongly affected by your server
choice, and the cheap RasPi is often one of the best for the job. Fot
$70 you can get a RasPi and a u-blox-8 hat. Add a few bits here and
there and you have a nifty stratum 1. You'll find its harder than it
looks to make a better NTP than that combo.
Then, once you have a strong baseline, you can see what tricks you
can do to improve on that.
RGDS
GARY
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
gem@rellim.com Tel:+1 541 382 8588
Veritas liberabit vos. -- Quid est veritas?
"If you can’t measure it, you can’t improve it." - Lord Kelvin
Yo Paride!
On Mon, 22 Jan 2018 16:38:01 +0100
Paride Legovini via time-nuts <time-nuts@febo.com> wrote:
> I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
> looking for a good and possibly affordable timing GPS receiver.
Before you bother looking at any GPS, you need to look at your server.
Hardly any Intel CPU can give you time resolution much better than
200 nS on a PPS in. Raspberry Pi's actually have slightly better
clock resolution than Intel parts, just under 190 nS.
That resolution os worse than what you get out of any good modern
GPS.
By 'local resolution' I mean the shortest time interval you can
read by repeatedly doing clock_systime() calls. clock_system() is
is many key ntpd paths.
The accuracy of your NTP server will be strongly affected by your server
choice, and the cheap RasPi is often one of the best for the job. Fot
$70 you can get a RasPi and a u-blox-8 hat. Add a few bits here and
there and you have a nifty stratum 1. You'll find its harder than it
looks to make a better NTP than that combo.
Then, once you have a strong baseline, you can see what tricks you
can do to improve on that.
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
gem@rellim.com Tel:+1 541 382 8588
Veritas liberabit vos. -- Quid est veritas?
"If you can’t measure it, you can’t improve it." - Lord Kelvin
AG
Achim Gratz
Mon, Jan 22, 2018 6:41 PM
Paride Legovini via time-nuts writes:
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
Unless you plan to use the timing receiver for some other function, it
really is overkill for the purpose of setting up an NTP server and
otherwise also requires you to set up a proper antenna in order to
benefit from the extra precision.
Am I overlooking something or missing interesting options?
I think that setting up at least three "good enough" NTP stratum-1
servers in your network gets you much better synchronization than trying
to get a single one more precise. To that end, you can set one up for
around $60 if you use a raspberryPi and a NavSpark mini w/ patch antenna
(if you have reasonable reception with that). You'll find that the NTP
clients will not see any measurable improvement once you have the NTP
servers down below 10µs deviation and it's possible to get each
individual server consistently below 1µs with a bit of care. Having at
least three stratum-1 in your network will keep the clients synchronized
correctly when inevitably one of the servers will have the occasional
problem that makes its time wander off for a while.
Regards,
Achim.
+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+
Factory and User Sound Singles for Waldorf Q+, Q and microQ:
http://Synth.Stromeko.net/Downloads.html#WaldorfSounds
Paride Legovini via time-nuts writes:
> I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
> looking for a good and possibly affordable timing GPS receiver.
Unless you plan to use the timing receiver for some other function, it
really is overkill for the purpose of setting up an NTP server and
otherwise also requires you to set up a proper antenna in order to
benefit from the extra precision.
> Am I overlooking something or missing interesting options?
I think that setting up at least three "good enough" NTP stratum-1
servers in your network gets you much better synchronization than trying
to get a single one more precise. To that end, you can set one up for
around $60 if you use a raspberryPi and a NavSpark mini w/ patch antenna
(if you have reasonable reception with that). You'll find that the NTP
clients will not see any measurable improvement once you have the NTP
servers down below 10µs deviation and it's possible to get each
individual server consistently below 1µs with a bit of care. Having at
least three stratum-1 in your network will keep the clients synchronized
correctly when inevitably one of the servers will have the occasional
problem that makes its time wander off for a while.
Regards,
Achim.
--
+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+
Factory and User Sound Singles for Waldorf Q+, Q and microQ:
http://Synth.Stromeko.net/Downloads.html#WaldorfSounds
DJ
David J Taylor
Tue, Jan 23, 2018 7:11 AM
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
[]
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
---===========
Paride,
As Mark notes, you don't need a timing precision GPS receiver for NTP, a
standard position GPS receiver is quite good enough providing it has a PPS
output. If you're thinking Raspberry Pi, there are some ready-made modules
such as:
https://store.uputronics.com/index.php?route=product/product&product_id=81
Stephen mentioned the newer series-8 ublox modules. These are indeed
excellent (and can receiver Galileo too), but a number of vendors
advertising series-8 modules (on both eBay and Amazon) are using remarked
series 5 or 6 chips without the series-8 functions. Use the ublox u-center
program to check anything you buy. From Amazon, at least, I got an
immediate refund.
73,
David GM8ARV
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-taylor@blueyonder.co.uk
Twitter: @gm8arv
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
[]
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
============================================
Paride,
As Mark notes, you don't need a timing precision GPS receiver for NTP, a
standard position GPS receiver is quite good enough providing it has a PPS
output. If you're thinking Raspberry Pi, there are some ready-made modules
such as:
https://store.uputronics.com/index.php?route=product/product&product_id=81
Stephen mentioned the newer series-8 ublox modules. These are indeed
excellent (and can receiver Galileo too), but a number of vendors
advertising series-8 modules (on both eBay and Amazon) are using remarked
series 5 or 6 chips without the series-8 functions. Use the ublox u-center
program to check anything you buy. From Amazon, at least, I got an
immediate refund.
73,
David GM8ARV
--
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-taylor@blueyonder.co.uk
Twitter: @gm8arv
PL
Paride Legovini
Tue, Jan 23, 2018 5:24 PM
On 2018-01-23 08:11, David J Taylor via time-nuts wrote:
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
[]
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
---===========
Paride,
As Mark notes, you don't need a timing precision GPS receiver for NTP
[...]
Stephen mentioned the newer series-8 ublox modules. These are indeed
excellent (and can receiver Galileo too)
Thanks David and thanks to you all for the advice you gave me, I
carefully read all your replies and learned quite a few things.
At this point I think I'll start tinkering with the cheapest module I
can get (and it will probably be a LEA-5T). Once I'll have everything
set up, if I'll be still having fun, I'll consider buying a newer
module, probably from the Ublox M8 family. We will see.
73,
Paride
On 2018-01-23 08:11, David J Taylor via time-nuts wrote:
> Dear fellow nuts,
>
> I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
> looking for a good and possibly affordable timing GPS receiver.
> []
> Am I overlooking something or missing interesting options?
>
> Cheers,
>
> Paride IZ3SUS
> ============================================
>
> Paride,
>
> As Mark notes, you don't need a timing precision GPS receiver for NTP
>
> [...]
>
> Stephen mentioned the newer series-8 ublox modules. These are indeed
> excellent (and can receiver Galileo too)
Thanks David and thanks to you all for the advice you gave me, I
carefully read all your replies and learned quite a few things.
At this point I think I'll start tinkering with the cheapest module I
can get (and it will probably be a LEA-5T). Once I'll have everything
set up, if I'll be still having fun, I'll consider buying a newer
module, probably from the Ublox M8 family. We will see.
73,
Paride
E
ewkehren
Tue, Jan 23, 2018 6:33 PM
The cheapest is not a 5T there are many 6 and 7 for $ 10. T gives you nothing unless you have saw tooth correctionBerrt Kehren
Sent from my Galaxy Tab® A
-------- Original message --------From: Paride Legovini via time-nuts time-nuts@febo.com Date: 1/23/18 12:24 PM (GMT-05:00) To: time-nuts@febo.com Subject: Re: [time-nuts] Suggestion for a timing GPS receiver (Trimble /
Ublox /other?)
On 2018-01-23 08:11, David J Taylor via time-nuts wrote:
Dear fellow nuts,
I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
looking for a good and possibly affordable timing GPS receiver.
[]
Am I overlooking something or missing interesting options?
Cheers,
Paride IZ3SUS
---===========
Paride,
As Mark notes, you don't need a timing precision GPS receiver for NTP
[...]
Stephen mentioned the newer series-8 ublox modules. These are indeed
excellent (and can receiver Galileo too)
Thanks David and thanks to you all for the advice you gave me, I
carefully read all your replies and learned quite a few things.
At this point I think I'll start tinkering with the cheapest module I
can get (and it will probably be a LEA-5T). Once I'll have everything
set up, if I'll be still having fun, I'll consider buying a newer
module, probably from the Ublox M8 family. We will see.
73,
Paride
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
The cheapest is not a 5T there are many 6 and 7 for $ 10. T gives you nothing unless you have saw tooth correctionBerrt Kehren
Sent from my Galaxy Tab® A
-------- Original message --------From: Paride Legovini via time-nuts <time-nuts@febo.com> Date: 1/23/18 12:24 PM (GMT-05:00) To: time-nuts@febo.com Subject: Re: [time-nuts] Suggestion for a timing GPS receiver (Trimble /
Ublox /other?)
On 2018-01-23 08:11, David J Taylor via time-nuts wrote:
> Dear fellow nuts,
>
> I plan to build a decent GPS/GNSS-based Stratum 1 NTP server, and I'm
> looking for a good and possibly affordable timing GPS receiver.
> []
> Am I overlooking something or missing interesting options?
>
> Cheers,
>
> Paride IZ3SUS
> ============================================
>
> Paride,
>
> As Mark notes, you don't need a timing precision GPS receiver for NTP
>
> [...]
>
> Stephen mentioned the newer series-8 ublox modules. These are indeed
> excellent (and can receiver Galileo too)
Thanks David and thanks to you all for the advice you gave me, I
carefully read all your replies and learned quite a few things.
At this point I think I'll start tinkering with the cheapest module I
can get (and it will probably be a LEA-5T). Once I'll have everything
set up, if I'll be still having fun, I'll consider buying a newer
module, probably from the Ublox M8 family. We will see.
73,
Paride
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