Small time server for mobile use.
Mark-
You might want to look at FEI-Zyfer, and their Nanosync line of products
http://www.fei-zyfer.com/time_sync.htm
I'm not sure about the pricing, but they look to meet your other
requirements
Dave
On Tue, May 12, 2015 at 1:11 PM, Mark Spencer mark@alignedsolutions.com
wrote:
Hi sorry for a possibly OT post.
Has anyone had practical experience with small commercially available time
servers / ntp servers suitable for mobile use in a vehicle.
The use case is I am in need of an accurate (ie. within 100 ms) time
source for several pc's in moving vehicle. Being able to run directly
off a 13.8 or 28 VDC source would be a major plus but AC power is also
available.
Hold over if there are gaps in GPS coverage is also a major plus.
We already have a GPS with a 1 pps output, but an integrated box with it's
own GPS would be best.
Yes I am aware I could feed a 1 pps signal into a laptop and use that as a
time server and I may end up going that route.
There is a small Ethernet LAN in the vehicle. The pc's currently get
their time via a wireless connection to various NTP servers. I need to be
able to ensure accurate time on the PC's if there is no wireless coverage.
This is for a one off project so piecing together various parts is an
option but a single box COTS solution would be nice. I've found a few
candidates via web searches but would welcome any feed back.
Thanks in advance
Mark Spencer
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On Wed, 13 May 2015 09:07:44 -0500
bownes bownes@gmail.com wrote:
For the advocates of RPi solutions, I put about half a dozen in to support
some non mission critical infrastructure about a year ago. We are using them
for for logging, reading QR codes, running a vending machine, kiosk web
browsers, and similar tasks. In short, nothing requiring heavily lifting.
I've been incredibly dissappointed in the results. Well over half of them
have needed replacement and not a one runs reliably. They need rebooting at
intervals from hours to a few tens of days to recover from total lock up.
The problem is not environmental, power or SD cards.
Do you know what the problem is?
I know that the RPI has pretty cheap design (like most of these super-cheap
SoC boards) and does suffer from a few problems. The most common one
is under-designed power supply. Together with the ultra-cheap wall-wart
supplies mostly used results in a quite decreased MTBF due to spikes/drops
on the power rails (BTW: soekris suffers from that too, just that a better
wall-wart supply doesn't help). Depending on the environment, in which
those boards are run, overheating might also be a problem.
Other than that, i am not aware of any software or hardware issues that
would cause the RPI, or any other board, to run unreliably.
Attila Kinali
--
< av500> phd is easy
< av500> getting dsl is hard
On 5/24/2015 5:46 AM, Attila Kinali wrote:
On Wed, 13 May 2015 09:07:44 -0500
bownes bownes@gmail.com wrote:
For the advocates of RPi solutions, I put about half a dozen in to support
some non mission critical infrastructure about a year ago. We are using them
for for logging, reading QR codes, running a vending machine, kiosk web
browsers, and similar tasks. In short, nothing requiring heavily lifting.
I've been incredibly dissappointed in the results. Well over half of them
have needed replacement and not a one runs reliably. They need rebooting at
intervals from hours to a few tens of days to recover from total lock up.
The problem is not environmental, power or SD cards.
Do you know what the problem is?
I know that the RPI has pretty cheap design (like most of these super-cheap
SoC boards) and does suffer from a few problems. The most common one
is under-designed power supply. Together with the ultra-cheap wall-wart
supplies mostly used results in a quite decreased MTBF due to spikes/drops
on the power rails (BTW: soekris suffers from that too, just that a better
wall-wart supply doesn't help). Depending on the environment, in which
those boards are run, overheating might also be a problem.
Other than that, i am not aware of any software or hardware issues that
would cause the RPI, or any other board, to run unreliably.
Attila Kinali
Many of the chips in the original PI run rather hot and need heatsinking
if used in other than free-air ambient temperatures. I've given up on
them for anything that I can't easily reset.
--
mailto:oz@ozindfw.net
Oz
POB 93167
Southlake, TX 76092 (Near DFW Airport)
I've noticed that on my RPI as well,
Time stability improved greatly when connected to a simple and well
cooled 7805 voltage
regulator. My RPI (GPS PPS) runs at about +/- 2 uS on a somewhat
medium CPU sytem
load. Good enough for my needs.
Frits
On 5/24/15, Attila Kinali attila@kinali.ch wrote:
On Wed, 13 May 2015 09:07:44 -0500
bownes bownes@gmail.com wrote:
For the advocates of RPi solutions, I put about half a dozen in to support
some non mission critical infrastructure about a year ago. We are using
them
for for logging, reading QR codes, running a vending machine, kiosk web
browsers, and similar tasks. In short, nothing requiring heavily lifting.
I've been incredibly dissappointed in the results. Well over half of them
have needed replacement and not a one runs reliably. They need rebooting
at
intervals from hours to a few tens of days to recover from total lock up.
The problem is not environmental, power or SD cards.
Do you know what the problem is?
I know that the RPI has pretty cheap design (like most of these super-cheap
SoC boards) and does suffer from a few problems. The most common one
is under-designed power supply. Together with the ultra-cheap wall-wart
supplies mostly used results in a quite decreased MTBF due to spikes/drops
on the power rails (BTW: soekris suffers from that too, just that a better
wall-wart supply doesn't help). Depending on the environment, in which
those boards are run, overheating might also be a problem.
Other than that, i am not aware of any software or hardware issues that
would cause the RPI, or any other board, to run unreliably.
Attila Kinali
--
< av500> phd is easy
< av500> getting dsl is hard
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.
--
vbradio.wordpress.com
I hesitate to say this for fear of provoking a fault, but although I
wouldn't consider them especially good, they're not universal failures. I
have a Pi running a house control and logging system that has an uptime of
230 days despite being largely unattended (I'm not on site - it doesn't get
any special treatment). It doesn't have a read-only filesystem, however all
logs are written to a USB stick.
On Sun, May 24, 2015 at 4:07 PM, Frister frister@gmx.net wrote:
I've noticed that on my RPI as well,
Time stability improved greatly when connected to a simple and well
cooled 7805 voltage
regulator. My RPI (GPS PPS) runs at about +/- 2 uS on a somewhat
medium CPU sytem
load. Good enough for my needs.
Frits
On 5/24/15, Attila Kinali attila@kinali.ch wrote:
On Wed, 13 May 2015 09:07:44 -0500
bownes bownes@gmail.com wrote:
For the advocates of RPi solutions, I put about half a dozen in to
support
some non mission critical infrastructure about a year ago. We are using
them
for for logging, reading QR codes, running a vending machine, kiosk web
browsers, and similar tasks. In short, nothing requiring heavily
lifting.
I've been incredibly dissappointed in the results. Well over half of
them
have needed replacement and not a one runs reliably. They need rebooting
at
intervals from hours to a few tens of days to recover from total lock
up.
The problem is not environmental, power or SD cards.
Do you know what the problem is?
I know that the RPI has pretty cheap design (like most of these
super-cheap
SoC boards) and does suffer from a few problems. The most common one
is under-designed power supply. Together with the ultra-cheap wall-wart
supplies mostly used results in a quite decreased MTBF due to
spikes/drops
on the power rails (BTW: soekris suffers from that too, just that a
better
wall-wart supply doesn't help). Depending on the environment, in which
those boards are run, overheating might also be a problem.
Other than that, i am not aware of any software or hardware issues that
would cause the RPI, or any other board, to run unreliably.
Attila Kinali
--
< av500> phd is easy
< av500> getting dsl is hard
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.
--
vbradio.wordpress.com
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
Hi sorry for a possibly OT post.
Has anyone had practical experience with small commercially available time
servers / ntp servers suitable for mobile use in a vehicle.
The use case is I am in need of an accurate (ie. within 100 ms) time source
for several pc's in moving vehicle. Being able to run directly off a 13.8
or 28 VDC source would be a major plus but AC power is also available.
Hold over if there are gaps in GPS coverage is also a major plus.
We already have a GPS with a 1 pps output, but an integrated box with it's
own GPS would be best.
Yes I am aware I could feed a 1 pps signal into a laptop and use that as a
time server and I may end up going that route.
There is a small Ethernet LAN in the vehicle. The pc's currently get their
time via a wireless connection to various NTP servers. I need to be able
to ensure accurate time on the PC's if there is no wireless coverage.
This is for a one off project so piecing together various parts is an option
but a single box COTS solution would be nice. I've found a few candidates
via web searches but would welcome any feed back.
Thanks in advance
Mark Spencer
Raspberry Pi perhaps?
http://www.satsignal.eu/ntp/Raspberry-Pi-quickstart.html
Cheers,
David
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-taylor@blueyonder.co.uk
If you already have a bunch f PCs running NTP why add one more? Just
run the PPS from your GS to one of the existing PCs Anklet t be a
stratum one. It's zero cost. For hold over "Orphan mode" works well
and will meet your 100 ms requirement. Again, it is zero cost.
On Sat, May 30, 2015 at 3:53 AM, David J Taylor
david-taylor@blueyonder.co.uk wrote:
Hi sorry for a possibly OT post.
Has anyone had practical experience with small commercially available time
servers / ntp servers suitable for mobile use in a vehicle.
The use case is I am in need of an accurate (ie. within 100 ms) time source
for several pc's in moving vehicle. Being able to run directly off a 13.8
or 28 VDC source would be a major plus but AC power is also available.
Hold over if there are gaps in GPS coverage is also a major plus.
We already have a GPS with a 1 pps output, but an integrated box with it's
own GPS would be best.
Yes I am aware I could feed a 1 pps signal into a laptop and use that as a
time server and I may end up going that route.
There is a small Ethernet LAN in the vehicle. The pc's currently get their
time via a wireless connection to various NTP servers. I need to be able
to ensure accurate time on the PC's if there is no wireless coverage.
This is for a one off project so piecing together various parts is an option
but a single box COTS solution would be nice. I've found a few candidates
via web searches but would welcome any feed back.
Thanks in advance
Mark Spencer
Raspberry Pi perhaps?
http://www.satsignal.eu/ntp/Raspberry-Pi-quickstart.html
Cheers,
David
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-taylor@blueyonder.co.uk
time-nuts mailing list -- time-nuts@febo.com
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--
Chris Albertson
Redondo Beach, California
Hi
Ok, how long will this driving around take?
If you are driving continuously with no GPS for 24 hours, your system needs to hold 100 ms
for 86,400 seconds. With a fixed frequency offset (rather than drift) that’s
0.1 / 86400 = 1.12 ppm.
If you want to spend money. Modify the clock in one or more of your PC’s to
run off of a cheap TCXO. Make those PC’s the “head ends” of your empire.
Set it up as Chris suggests and move on. NTP has all the “stuff” in it to work out the
frequency offset of the TCXO and take care of any drift.
Cheap, easy, redundant, reliable … what’s not to like :)
Bob
On May 31, 2015, at 5:50 AM, Chris Albertson albertson.chris@gmail.com wrote:
If you already have a bunch f PCs running NTP why add one more? Just
run the PPS from your GS to one of the existing PCs Anklet t be a
stratum one. It's zero cost. For hold over "Orphan mode" works well
and will meet your 100 ms requirement. Again, it is zero cost.
On Sat, May 30, 2015 at 3:53 AM, David J Taylor
david-taylor@blueyonder.co.uk wrote:
Hi sorry for a possibly OT post.
Has anyone had practical experience with small commercially available time
servers / ntp servers suitable for mobile use in a vehicle.
The use case is I am in need of an accurate (ie. within 100 ms) time source
for several pc's in moving vehicle. Being able to run directly off a 13.8
or 28 VDC source would be a major plus but AC power is also available.
Hold over if there are gaps in GPS coverage is also a major plus.
We already have a GPS with a 1 pps output, but an integrated box with it's
own GPS would be best.
Yes I am aware I could feed a 1 pps signal into a laptop and use that as a
time server and I may end up going that route.
There is a small Ethernet LAN in the vehicle. The pc's currently get their
time via a wireless connection to various NTP servers. I need to be able
to ensure accurate time on the PC's if there is no wireless coverage.
This is for a one off project so piecing together various parts is an option
but a single box COTS solution would be nice. I've found a few candidates
via web searches but would welcome any feed back.
Thanks in advance
Mark Spencer
Raspberry Pi perhaps?
http://www.satsignal.eu/ntp/Raspberry-Pi-quickstart.html
Cheers,
David
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-taylor@blueyonder.co.uk
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
--
Chris Albertson
Redondo Beach, California
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