Try this link www.serc.iisc.ernet.in/graduation-theses/babu_09.pdf
seems interesting
On Wed, Feb 1, 2012 at 1:44 AM, Magnus Danielson mag...@rubidium.dyndns.org
wrote:
On 01/02/12 01:29, Chris Albertson wrote:
On Mon, Jan 30, 2012 at 6:17 PM, Didier Jugesshali...@gmail.com wrote:
You have
On Tue, 31 Jan 2012 16:29:07 -0800
Chris Albertson albertson.ch...@gmail.com wrote:
I'm pretty sure those GPS recievers that send out more frequent data,
at say 2Hz or 5Hz are just interpolating. It is not more accurate.
The GPS sats only send a frame once over 6 seconds.
As Magnus already
On Tue, 31 Jan 2012 21:19:50 + (UTC)
cfo xne...@luna.kyed.com wrote:
You want these for the MCU
http://www.st.com/internet/mcu/product/252140.jsp
Thanks! The links worked... Dunno why using the webpage does not...
Maybe some strange interferance with my firefox version and their
On Tue, 31 Jan 2012 15:27:45 -0800
Chris Albertson albertson.ch...@gmail.com wrote:
On Tue, Jan 31, 2012 at 11:43 AM, Attila Kinali att...@kinali.ch wrote:
My current progress is that the uC i wanted to use does not
do what i want. Can anyone recommend a uC with 32bit timers
and IEEE
On Wed, 01 Feb 2012 01:52:16 +0100
Magnus Danielson mag...@rubidium.dyndns.org wrote:
On 31/01/12 20:43, Attila Kinali wrote:
On Tue, 31 Jan 2012 18:50:08 +0100
b...@lysator.liu.se wrote:
Exactly that _is_ the appeal of the Tbolts.
Yes, but can this be replicated with a standard GPS
On Tue, 31 Jan 2012 16:21:40 -0800
Tom Van Baak t...@leapsecond.com wrote:
We're waiting for some brave soul to implement an SDR-based
GPS timing receiver; we can all then experiment with the TBolt
model instead of the TIC/DAC model of GPSDO.
I'm planning that... I don't think it's too
Chris,
Most of the high-end GPS receivers offer faster rates than 1 Hz.
This is required for RTK work, for example. It is not interpolation.
It is hard and accurate and wonderful and expensive. Remember
there is a lot of information in the phase and doppler of both the
code and the carrier
On Wed, 01 Feb 2012 01:13:13 +0100
Magnus Danielson mag...@rubidium.dyndns.org wrote:
http://www.bbc.co.uk/blogs/researchanddevelopment/2012/01/implementing-startoffsettime-f.shtml
This is really a side-track to the normal time-nuts issues, but it is
interesting to note that there are
On Tue, 31 Jan 2012 16:29:07 -0800
Chris Albertson albertson.ch...@gmail.com wrote:
I'm pretty sure those GPS recievers that send out more frequent data,
at say 2Hz or 5Hz are just interpolating. It is not more accurate.
The GPS sats only send a frame once over 6 seconds.
As Magnus
I have opened the FTS125: the fixed OCXO 20MHz is fed using the EXT_CLK pin
7 on the CW25. Maybe it is possible to drive a CW12 with an external high
quality 20MHz but maybe a suitable firmware is then needed.
On Wed, Feb 1, 2012 at 10:28 AM, Attila Kinali att...@kinali.ch wrote:
On Tue, 31 Jan
In your opinion, is it possible for a GPS receiver to align the PPS pulse
on multiple of the C/A code repetition rate because of (for example) badly
received satellite signals? Maybe this can happen, after the initial
acquisition, on the following updates.
On Wed, Feb 1, 2012 at 10:47 AM,
Yes. If you look up old papers, they already did this with Oncores,
Cesium clocks and synthesis.
I have not seen any such papers yet. Do you have any pointers or hints
what to search for?
Attila,
I don't have a link either. I would look at the usual TF web sources:
PTTI, NIST, FCS, EFTF,
Hi all,
Before I put it on ebay,
anyone in the group want an immaculate National Instruments USB to GPIB
converter?
$250 (US) or £150 (UK/EU) including shipping. They seem to go for £200/$300 at
auction.
Payment by paypal to this email address.
Regards,
Robert G8RPI
There've been numerous threads on the Gnuradio mailing list about code
to receive GPS using the Ettus Research USRP hardware. I don't know
whether anyone has actually made it work, but it appears that it's been
the subject of quite a few academic projects.
John
On 2/1/2012 4:28 AM,
All this talk about microcontrollers and IEEE1588 made me get out of the
shadow to ask:
1) Are you talking about IEEE1588-2002 or IEEE1588-2008? The former has
no use to me, but the later could replace some GPSs in a system i´m
designing...
2) If you intend to play with IEEE1588-2008, do
Interesting: a sort of public grandmaster. I don't think there are any
available. I have attended an Oscilloquartz's live meeting on IEEE1588 and,
of course, they have shown their expensive production but, in general, it
should be useful to find public grandmasters to test with.
On Wed, Feb 1,
Hi,
I would be interest in receiving the manual.
Best regards,
Sal C. Cornacchia
Electronic RF Microwave Engineer (Ret.)
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
On Wed, Feb 1, 2012 at 6:09 AM, Daniel Mendes dmend...@gmail.com wrote:
All this talk about microcontrollers and IEEE1588 made me get out of the
shadow to ask:
1) Are you talking about IEEE1588-2002 or IEEE1588-2008? The former has no
use to me, but the later could replace some GPSs in a
Hi
The gotcha with a public grandmaster is routing to it. Without 1588
routers / hubs / switches / what ever, the result is compromised. You fall
back into the same routing delay mess as NTP. Since public pretty much means
internet accessible, you would need to upgrade a lot of stuff. Since that
Hi
It's amazing how good a job Google can do on something like that. Of course,
it may have been converted to Russian with Google in the first place ...
Looking at the manual, it's certainly for a similar part. It also is from
the right era for our parts. You could make a lot out of the fact
On Wed, Feb 1, 2012 at 8:19 AM, Attila Kinali att...@kinali.ch wrote:
On Wed, 01 Feb 2012 09:07:23 -0500
John Ackermann N8UR j...@febo.com wrote:
There've been numerous threads on the Gnuradio mailing list about code
to receive GPS using the Ettus Research USRP hardware. I don't know
Hi
To bring this back to the original point - will it help?
The basic assumption (I think) was that having multiple corrections per
second would make those corrections smaller. Since that's not the way short
term stability and noise normally works, my guess would be not. If you have
a receiver
On Wed, Feb 1, 2012 at 9:24 AM, Bob Camp li...@rtty.us wrote:
Hi
It's amazing how good a job Google can do on something like that. Of course,
it may have been converted to Russian with Google in the first place ...
Looking at the manual, it's certainly for a similar part. It also is from
The challenge with public grandmasters is that the delay variation introduced
by the intervening network destroys the time accuracy.
Greg Dowd
gdowd at symmetricom dot com (antispam format)
Symmetricom, Inc.
www.symmetricom.com
A clever person solves a problem. A wise person avoids it. Albert
I wish Rob Kimberley's email address had been preserved so I could also
ask for this manual pdf file without adding traffic to TimeNuts.
Chris Albertson offered to post the manual on-line to simplify this. I
hope that is arranged by someone!
However it be available, I want a copy of the
On Wed, 1 Feb 2012 09:27:30 -0800, Chris Albertson
albertson.ch...@gmail.com wrote:
On Wed, Feb 1, 2012 at 8:19 AM, Attila Kinali att...@kinali.ch wrote:
On Wed, 01 Feb 2012 09:07:23 -0500
John Ackermann N8UR j...@febo.com wrote:
There've been numerous threads on the Gnuradio mailing list
Hi
At least the Russian version has the 60 MHz VCXO in it, and the correct
tuning resolution. It's certainly closer than anything else I've seen.
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of Chris Albertson
Sent: Wednesday,
If someone sends me the manual, I have a location I can host it.
Bob
On Wed, Feb 1, 2012 at 12:38 PM, Larry McDavid lmcda...@lmceng.com wrote:
I wish Rob Kimberley's email address had been preserved so I could also
ask for this manual pdf file without adding traffic to TimeNuts.
Chris
Hi
My guess is that the reality of parts sourcing will quickly get us right
back to the group buy of LEA-6T topic.
Bob
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of David
Sent: Wednesday, February 01, 2012 12:38 PM
To: Discussion of
On Wed, Feb 1, 2012 at 9:20 AM, Bob Camp li...@rtty.us wrote:
Hi
The gotcha with a public grandmaster is routing to it. Without 1588
routers / hubs / switches / what ever, the result is compromised. You fall
back into the same routing delay mess as NTP. Since public pretty much means
I Don't know what problem you all are having.
Rob Kimberley's email address (robkimber...@btinternet.com) is present
plain as day in the from header of his post.
subject was :
Re: [time-nuts] FE-.5680A trimming resolution
posted 1/31/2012 4:14PM
Master your email or it will master you!
Dale
On Wed, 1 Feb 2012 09:27:30 -0800
Chris Albertson albertson.ch...@gmail.com wrote:
I thought it might be interresting but then found out you need to buy
$2,000+ worth of hardware for even start experimenting.Open Source
SDR needs to run on a common affordable platform or it will never gain
eBay's nichegeek sent me this links. I have not yet checked them out.
http://www.vectron.com/products/ocxo/C4550A2-0275.pdf
http://www.leapsecond.com/museum/fei5650a/
http://www.vk3um.com/Reference Data/Reference Locking the IC-910.pdf
___
time-nuts
Group the following material may be out of context of the normal subject
matter, but take notice of the underlined portion in the second paragraph.
FCC Asks If You and GPS Should Be Protected from Interference
“We invite comment on LightSquared’s petition, and establish a pleading cycle.”
On Wed, 1 Feb 2012 12:43:55 -0500
Bob Camp li...@rtty.us wrote:
My guess is that the reality of parts sourcing will quickly get us right
back to the group buy of LEA-6T topic.
As i just wrote in reply to Chris Albertson, sourcing is not really
an issue, as long as you don't strive for highly
On Wed, Feb 1, 2012 at 9:43 AM, Bob Camp li...@rtty.us wrote:
Hi
My guess is that the reality of parts sourcing will quickly get us right
back to the group buy of LEA-6T topic.
For timing I don't see why an LEA-6T is better then a Oncore or
t-bolt. You can buy an Oncore UT for about $18 on
Chris Albertson wrote:
The combination of a network server and a GPS receiver is called a
Grand Master. It is not expensive to set one up. Any low-end PC
hardware that has a real serial port and then a good timing grade GPS.
You can't get away from the need to have at least one GPS
In message 20120201191226.f6273dcef860b157b817a...@kinali.ch, Attila Kinali w
rites:
but it's possible.
Today we have so much electronic that works in the 2.4GHz band that
we have many devices at our disposal.
It's not uncommon for mobile phone frontends to span 600MHz-4GHz these
days, so I
On Wed, Feb 1, 2012 at 10:18 AM, Attila Kinali att...@kinali.ch wrote:
That said. I've contacted u-blox, but got a number that is way out of
what i've expected (approx 120CHF). I'm currently trying to get a lower
price.
What is it these u-blox device can do that a cheaper Motorola Oncore
That is also what I like to understand, and when combined with a FE 5680A
the time will be long and should be averaged over 100 if not 1000 samples,
what is the advantage? Look at the error budget.
Bert Kehren
In a message dated 2/1/2012 2:04:04 P.M. Eastern Standard Time,
There's no requirement for a grandmaster to be hooked up to GPS. It may just
as well work
off its own oscillator. A grandmaster is the ultimate source of time in a PTP
network. It is
not relevant what its time source is.
That is correct. It can use any kind of reference clock. GPS is the
Chris,
When you're down at the ns level, every ns counts even more.
There actually a huge difference between a UT and VP and
M12 and ...
Then again, it's not always about nanoseconds. There are also
issues of power and size, support, supply, price, the future.
Perhaps also RF sensitivity,
I think, a specialized GPS SDR can be build for less than 500 USD
in low (a dozen at max) volumes.
The USRP works for GPS L1 (though P/Y is a little undersampled at 8
Ms/s complex), but I didn't find a way to acquire both L1 and L2
simultaneously at useful sample rates (maybe current USRP
On Wed, 1 Feb 2012 11:03:19 -0800
Chris Albertson albertson.ch...@gmail.com wrote:
On Wed, Feb 1, 2012 at 10:18 AM, Attila Kinali att...@kinali.ch wrote:
That said. I've contacted u-blox, but got a number that is way out of
what i've expected (approx 120CHF). I'm currently trying to get a
Simple:
the ublox will just work when you apply power and have a good antenna. The
Motorola units have all sorts of idiosyncrasies, such as sometimes taking a
very long time to achieve a lock, having the Almanac get corrupted and not
lock when the battery backup is getting low, having
On 01/02/12 12:35, Azelio Boriani wrote:
In your opinion, is it possible for a GPS receiver to align the PPS pulse
on multiple of the C/A code repetition rate because of (for example) badly
received satellite signals? Maybe this can happen, after the initial
acquisition, on the following
On Wed, 1 Feb 2012 11:49:51 -0800
Peter Monta pmo...@gmail.com wrote:
One possible inexpensive design:
- RF input passively split three ways, with LC filters for the three
channels: L5/E5, L2, and L1/E1/Glonass
- For each channel, a downconverter (Maxim MAX2121) feeding a ~65 Ms/s
ADC
On 01/02/12 10:35, Attila Kinali wrote:
On Wed, 01 Feb 2012 01:13:13 +0100
Magnus Danielsonmag...@rubidium.dyndns.org wrote:
http://www.bbc.co.uk/blogs/researchanddevelopment/2012/01/implementing-startoffsettime-f.shtml
This is really a side-track to the normal time-nuts issues, but it is
Can I ask where does the Trimble Resolution-T fit between this other receivers
? I've used it and I do like it. I thought it was relatively modern and capable
compared to the Oncore.
Isn't it comparable to the uBlox for example?
Regards,
Roberto EB4EQA
From: albertson.ch...@gmail.com
On Wed, Feb 1, 2012 at 1:29 AM, Tom Van Baak t...@leapsecond.com wrote:
Most of the high-end GPS receivers offer faster rates than 1 Hz.
This is required for RTK work, for example. It is not interpolation.
It is hard and accurate and wonderful and expensive.
My comments were about the GPS
I too would be interested in a pdf copy. Ideally in the way of an FTP
or WWW source. I am not too sure that gmail could handle 1MB.
Thanks Geoff
--
#
Geoff Blake, G8GNZ JO01fq: Chelmsford, Essex, UK
ge...@palaemon.co.uk or
Being divorced and no children writing a large check is neither a problem
nor a challenge. To me the challenge is to find solutions that are
affordable and work for every body. Sadly there is very little interest or
emphasis
in this group on this. An example the $ 10 Loran C simulator
Chris,
Pretty sure (I haven't downloaded it again to verify) that the version
you found is TM0110-2 which has been available for quite a long time.
Rob's and the Russian version seem to be TM 5680-0211 as stated in the
title.
As Bob points out, they are not the same, although the 0211
On Wed, Feb 1, 2012 at 1:46 PM, Rex r...@sonic.net wrote:
Chris,
Pretty sure (I haven't downloaded it again to verify) that the version you
found is TM0110-2 which has been available for quite a long time. Rob's and
the Russian version seem to be TM 5680-0211 as stated in the title.
I just
Hi
If you are running the newer version of 1588 *and* have good 1588 switches /
hubs, you can indeed run at sub microsecond levels. The same is true of
routers, again if they are designed with 1588 goodies inside them. Neither
box is a common item. The routers are even less common than the
On 01/02/12 21:32, Chris Albertson wrote:
On Wed, Feb 1, 2012 at 1:29 AM, Tom Van Baakt...@leapsecond.com wrote:
Most of the high-end GPS receivers offer faster rates than 1 Hz.
This is required for RTK work, for example. It is not interpolation.
It is hard and accurate and wonderful and
If you do not limit yourself to NMEA you can get L1/L2 C/A and P-code and
both code and carrier phase in rates higher than 1 Hz. I have such
receivers, and you can get them as modules.
NMEA was designed for boat navagation and works well for that. I
don't need NMEA for timing. What can I
On 01/02/12 18:41, Bob Camp wrote:
Hi
At least the Russian version has the 60 MHz VCXO in it, and the correct
tuning resolution. It's certainly closer than anything else I've seen.
Which is why I wanted to report on the link. It's also interesting to
see the set of frequencies coming out of
On 02/02/12 00:17, Chris Albertson wrote:
If you do not limit yourself to NMEA you can get L1/L2 C/A and P-code and
both code and carrier phase in rates higher than 1 Hz. I have such
receivers, and you can get them as modules.
NMEA was designed for boat navagation and works well for that. I
On 01/02/12 10:25, Attila Kinali wrote:
On Wed, 01 Feb 2012 01:52:16 +0100
Magnus Danielsonmag...@rubidium.dyndns.org wrote:
On 31/01/12 20:43, Attila Kinali wrote:
On Tue, 31 Jan 2012 18:50:08 +0100
b...@lysator.liu.se wrote:
Exactly that _is_ the appeal of the Tbolts.
Yes, but can
Can you take a minute and explain how to actually post a comment.
Your link brings up a blank search screen. I can use that to see
the notice and comments but it is not clear how to create and post
comments.
On Wed, Feb 1, 2012 at 10:12 AM, John Darwin Powers j...@cornell.edu wrote:
Group
On 01/02/12 15:07, John Ackermann N8UR wrote:
There've been numerous threads on the Gnuradio mailing list about code
to receive GPS using the Ettus Research USRP hardware. I don't know
whether anyone has actually made it work, but it appears that it's been
the subject of quite a few academic
In my opinion the work done locking the VCTCXO of the Oncore is different
from the TBolt OCXO management: the TBolt steers the OCXO based on the
received signal instead they locked the Oncore oscillator to a Cs
reference. Yes, if all the world is the same then there is no difference:
the Cs locks
On 01/02/12 19:12, Attila Kinali wrote:
On Wed, 1 Feb 2012 09:27:30 -0800
Chris Albertsonalbertson.ch...@gmail.com wrote:
I thought it might be interresting but then found out you need to buy
$2,000+ worth of hardware for even start experimenting.Open Source
SDR needs to run on a common
Hi All,
I've been lurking here for a while, learning lots - but I think I may be
able to contribute something to this discussion.
I have been looking at SDR GPS reception for a while, and have a number of
ideas as to how to go about this process. My first point of call is the
layout of a board
On 01/02/12 18:52, Chris Albertson wrote:
On Wed, Feb 1, 2012 at 9:20 AM, Bob Campli...@rtty.us wrote:
Hi
The gotcha with a public grandmaster is routing to it. Without 1588
routers / hubs / switches / what ever, the result is compromised. You fall
back into the same routing delay mess as
The 15 pin connector (near crystal oscillator) is used for JTAG programming
the XC8572XL (XC) and the PSD813F1V (PSD).
According to my analysis the pinout is the following:
1) Vcc/+5V - goes to pin 5 of MAX882 voltage regulator: its 3.3V output
powers XC and PSD
2) Ground (GND)
3) PSD pin PC6
And now for something completely different:
Here I am with all of this precision time equipment, and I still
have to manually set time on the Digital Video Recorders (DVR)
because the TV channels that used to send a time code that the
DVR understood no longer do so. Seems like it died when
Nice pix
Thanks
On Wed, Feb 1, 2012 at 8:50 PM, Elio Corbolante elio...@gmail.com wrote:
The 15 pin connector (near crystal oscillator) is used for JTAG programming
the XC8572XL (XC) and the PSD813F1V (PSD).
According to my analysis the pinout is the following:
1) Vcc/+5V - goes to pin 5 of
Javier Herrero's exciting DDS discovery led to this plot of the unit
tweaking the frequency (cmd 0x22):
http://n5tnl.com/time/fe-5680a/graphs/dds_autotuning.png
It appears to make an adjustment even before lock!
--
newell N5TNL
___
time-nuts
On 2/1/12 9:27 AM, Chris Albertson wrote:
On Wed, Feb 1, 2012 at 8:19 AM, Attila Kinaliatt...@kinali.ch wrote:
On Wed, 01 Feb 2012 09:07:23 -0500
John Ackermann N8URj...@febo.com wrote:
There've been numerous threads on the Gnuradio mailing list about code
to receive GPS using the Ettus
On 2/1/12 10:12 AM, Attila Kinali wrote:
On Wed, 1 Feb 2012 09:27:30 -0800
Chris Albertsonalbertson.ch...@gmail.com wrote:
I thought it might be interresting but then found out you need to buy
$2,000+ worth of hardware for even start experimenting.Open Source
SDR needs to run on a common
On 2/1/12 12:22 PM, Attila Kinali wrote:
On Wed, 1 Feb 2012 11:49:51 -0800
Peter Montapmo...@gmail.com wrote:
One possible inexpensive design:
- RF input passively split three ways, with LC filters for the three
channels: L5/E5, L2, and L1/E1/Glonass
- For each channel, a downconverter
http://www.rhodiatoce.com/pics/time-nuts/FE-5680A_annotated.jpg
Excellent work! I look forward to any further info.
Great picture with the pins and some parts labelled. By the way, if you
want you could add the frequencies going into and out of the Xilinx
XC9572XL CPLD part:
Pin 64: 60
Failing that, can the crystal that determines time for the DVR be adjusted?
What sort of crystals do you find inside? My guess is there are two of them,
one at 32KHz used for timekeeping, and one at ?? MHz for the CPU.
I think I've seen comments about making 32 KHz from 10 MHz in a PIC or
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