Re: [time-nuts] What is considered the best deal now days on ...

[Pete Lancashire]

Yeah the 10 megahertz thing was me not thinking very well. It's somewhere
in the back of my mind I remember I think a korean-made (?) model did 10 out

On Thu, May 3, 2018, 5:16 PM Bob kb8tq  wrote:

> Hi
>
> Outputs a pps is not impossible to find on an L1 / L2 receiver. Outputs 10
> MHz is
> very unusual on an L1 / L2 device.
>
> Bob
>
> > On May 3, 2018, at 7:42 PM, Pete Lancashire 
> wrote:
> >
> > ... a L1 / L2 receiver that also outputs either one PPS or 10 megahertz
> >
> > -pete
> > ___
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Re: [time-nuts] What is considered the best deal now days on ...

[Bob kb8tq]

Hi

Outputs a pps is not impossible to find on an L1 / L2 receiver. Outputs 10 MHz 
is 
very unusual on an L1 / L2 device.

Bob

> On May 3, 2018, at 7:42 PM, Pete Lancashire  wrote:
> 
> ... a L1 / L2 receiver that also outputs either one PPS or 10 megahertz
> 
> -pete
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[time-nuts] What is considered the best deal now days on ...

[Pete Lancashire]

... a L1 / L2 receiver that also outputs either one PPS or 10 megahertz

-pete
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Re: [time-nuts] nuts about position (cheap receiver)

[Bob kb8tq]

Hi

…… and the quoted errors are in the 10’s of cm range. Thus you need a few years,
even if you are moving an inch per year. 

Bob

> On May 3, 2018, at 2:19 PM, Hal Murray  wrote:
> 
> 
> kb...@n1k.org said:
>> If you have a very good survey grade receiver and take a long enough data
>> set, yes you can  watch your location drift in some parts of the world. In
>> most locations, fixes a few years apart would be a better bet. 
> 
> I'm in Silicon Valley.  The San Andreas fault is a few miles from here.  A 
> map of the bay area will show a dozen major faults.  A neighborhood map may 
> have several smaller lines.
>  https://earthquake.usgs.gov/earthquakes/events/1906calif/virtualtour/bayarea
> .php
> 
> The USGS has good GPS receivers sprinkled around the area.  You can see 
> occasional
> antenna domes on a post alongside the highway.
>  http://www.quake.geo.berkeley.edu/usgs-gps/
> (Time sink warning.)
> 
> The fault moves about as fast as your fingernails grow, an inch per year.  
> That's one side relative to the other.  I don't know how fast the pair is 
> moving.
> 
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
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[time-nuts] Yale physicists find signs of a time crystal

[Brooke Clarke]

Hi:

The actual Yale papers are behind a paywall.
https://news.yale.edu/2018/05/02/yale-physicists-find-signs-time-crystal
"Time crystals, first identified in 2016, are different. Their atoms spin periodically, first in one direction and then 
in another, as a pulsating force is used to flip them. That’s the “ticking.” In addition, the ticking in a time crystal 
is locked at a particular frequency, even when the pulse flips are imperfect."


But here is some public stuff:
https://en.wikipedia.org/wiki/Time_crystal

Observation of a Discrete Time Crystal
https://arxiv.org/pdf/1609.08684v1.pdf
"However, nonequilibrium Floquet systems subject to a periodic drive can exhibit persistent time-correlations at an 
emergent sub-harmonic frequency7–10. This new phase of matter has been dubbed a “discrete time crystal” (DTC)10,11. 
Here, we present the first experimental observation of a discrete time crystal, in an interacting spin chain of trapped 
atomic ions.


--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

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[time-nuts] HP 58503A Flashing Front Panel LEDs

[Michael Jasper]

Hi,

I recently purchased an HP 58503A from eBay. When I power it on, with or 
without an antenna, the power LED illuminates on the front panel, followed by 
each LED one at a time. Then, after a moment, the unit alternates between all 
front panel LEDs being illuminated and only the power LED at a rate of about 
once every 3 seconds. I opened the unit and checked the rail voltages. I have 
5.22V, +15.01V, -15.00V. The oven is warming. There are some LEDs on the board 
near the antenna jack and I have two red illuminated and a single green. I 
can’t get anything on the serial port.

Has anyone seen this before? I have a 30 day ROR but I like this model and 
would love to fix it if anyone has any advice.

Thanks,
Mike

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Re: [time-nuts] nuts about position (cheap receiver)

[Hal Murray]

kb...@n1k.org said:
> If you have a very good survey grade receiver and take a long enough data
> set, yes you can  watch your location drift in some parts of the world. In
> most locations, fixes a few years apart would be a better bet. 

I'm in Silicon Valley.  The San Andreas fault is a few miles from here.  A 
map of the bay area will show a dozen major faults.  A neighborhood map may 
have several smaller lines.
  https://earthquake.usgs.gov/earthquakes/events/1906calif/virtualtour/bayarea
.php

The USGS has good GPS receivers sprinkled around the area.  You can see 
occasional
antenna domes on a post alongside the highway.
  http://www.quake.geo.berkeley.edu/usgs-gps/
(Time sink warning.)

The fault moves about as fast as your fingernails grow, an inch per year.  
That's one side relative to the other.  I don't know how fast the pair is 
moving.



-- 
These are my opinions.  I hate spam.



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Re: [time-nuts] Racal 9475 Rubidium

[Dan Rae]

On 5/3/2018 9:55 AM, Bob kb8tq wrote:

Hi

You *really* need to keep the baseplate of the FRK series devices down. Their 
reliability drops quite a bit
as you go from 40 to 50 to 60 C on the baseplate. I would avoid boosting the 
input voltage without a very
good heatsink ( or heatsink + fan ) setup.

I just measured mine after about two hours of warm up, the case sides 
(which also are a sort of sink) measure around 33C, and the rear heat 
sink around 34C in a fairly chilly (17C :^) ) southern California room.  
I don't think it's ever going to cook the FRK which has been working 
when needed, as I just discovered, since 2001.


Dan
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Re: [time-nuts] Racal 9475 Rubidium

[Paul Bicknell]

Hi Dan 
Regarding a photographs of the back of your 9475 as my unit dues not have a
heat sing and it is serial number  B002 so your offer would be useful

Regards Paul B

-Original Message-
From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Rae
Sent: 03 May 2018 16:38
To: time-nuts@febo.com
Subject: Re: [time-nuts] Racal 9475 Rubidium

On 5/3/2018 7:38 AM, Adrian Godwin wrote:
> What sort of heatsink does it need ? Do you need the original part or
would
> a lightly-machined generic module do ?
>
At the time, at least in the UK, it was a very common extrusion, often 
used for power supplies etc., and in fact I see two on the back of big 
Astron supplies under my bench.  I had some in my "junk box" that even 
had the mounting holes in the correct places.   If anyone needs it I can 
take photographs of the back of my 9475 with the heatsink fitted.

Dan
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Re: [time-nuts] nuts about position (cheap receiver)

[J Grizzard]

On 5/3/2018 9:26 AM, Mark Sims wrote:

Those results were with the "ultra rapid" orbits.  It will be interesting to 
see what they look like when the final precise orbits are available in a couple of weeks.

I also need to see how those values compare to Lady Heather's precision survey 
results.


FWIW, a dual-frequency PPP run I did late last year has the following 
uncertainties, when processed with the various IGS precision 
ephemerides, via AUSPOS:


    longitude   latitude  altitude
IGS UltraRapid 0.004m 0.003m    0.013m
IGS Rapid  0.004m 0.003m    0.012m
IGS Final  0.004m 0.003m 0.012m

The computed ECEF coordinates change by 0.003m(X) and 0.001m(Z) between 
UltraRapid and Final.


...so really not much of a difference between UltraRapid and Final, at 
least for a dual-frequency survey at my location.


*digs through old stuff*

Okay, found a single-frequency survey from mid-last-year, processed by CSRS:

    longitude   latitude  altitude
NRCan Rapid    0.103m    0.121m 0.253m
IGS Final  0.103m 0.121m 0.252m

...not much difference there, either.

Both of these were with a roof-mounted antenna and a good skyview, 
running 24 hours. The first was one measurement every 15 seconds, the 
latter one measurement per second. (I think for these purposes, one 
measurement every 15 seconds is more than sufficient and makes the files 
process *so* much faster).


-j
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Re: [time-nuts] nuts about position (cheap receiver)

[Ole Petter Ronningen]

In my experience, there is little difference between the Final and Rapid,
which will be out just about now (for yesterdays observations)

Ole

On Thu, May 3, 2018 at 6:26 PM Mark Sims  wrote:

> To give an idea about the possible improvement in antenna location
> available by post-processing the data,  I first did a 2 hour self-survey
> and that put the receiver into position hold mode.  Then I collected RINEX
> data for 16 hours.   The post-processed lat/lon/alt values differed around
> 1/1/3 meters better than the self-survey values (with estimated error
> ellipses of 0.17/0.15/0.4 meters).   Those results were with the "ultra
> rapid" orbits.  It will be interesting to see what they look like when the
> final precise orbits are available in a couple of weeks.
>
> I also need to see how those values compare to Lady Heather's precision
> survey results.
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Re: [time-nuts] Racal 9475 Rubidium

[Bob kb8tq]

Hi

You *really* need to keep the baseplate of the FRK series devices down. Their 
reliability drops quite a bit
as you go from 40 to 50 to 60 C on the baseplate. I would avoid boosting the 
input voltage without a very
good heatsink ( or heatsink + fan ) setup. 

I’ve …. ummm ….. cooked … a number of FRK’s over the years. 

Bob

> On May 3, 2018, at 12:40 PM, Nick Sayer via time-nuts  
> wrote:
> 
> 
> 
>> On May 2, 2018, at 7:13 PM, Roger Tilsley  wrote:
>> 
>> 
>> 
>> In my experience, FRK modules produce their best performance when operated  
>> from a supply voltage between 27 V and 28 V, selected for individual units 
>> but 27.6 V is a good starting figure. 
> 
> Would there be any value to designing a 24 -> 27.5 volt boost converter that 
> one could use to power it from a more conventional supply? How much current 
> would it need?
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Re: [time-nuts] Racal 9475 Rubidium

[Nick Sayer via time-nuts]

> On May 2, 2018, at 7:13 PM, Roger Tilsley  wrote:
> 
> 
> 
> In my experience, FRK modules produce their best performance when operated  
> from a supply voltage between 27 V and 28 V, selected for individual units 
> but 27.6 V is a good starting figure. 

Would there be any value to designing a 24 -> 27.5 volt boost converter that 
one could use to power it from a more conventional supply? How much current 
would it need?
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[time-nuts] nuts about position (cheap receiver)

[Mark Sims]

To give an idea about the possible improvement in antenna location available by 
post-processing the data,  I first did a 2 hour self-survey and that put the 
receiver into position hold mode.  Then I collected RINEX data for 16 hours.   
The post-processed lat/lon/alt values differed around 1/1/3 meters better than 
the self-survey values (with estimated error ellipses of 0.17/0.15/0.4 meters). 
  Those results were with the "ultra rapid" orbits.  It will be interesting to 
see what they look like when the final precise orbits are available in a couple 
of weeks.

I also need to see how those values compare to Lady Heather's precision survey 
results.
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Re: [time-nuts] Racal 9475 Rubidium

[Adrian Godwin]

Like this one ?

Yes, very common - I'm sure something suitable could be found, if not in my
junkbox then at an amateur radio sale.

http://radioattic.com/images/martin/Martin_Astron_RS-20A_more.jpg

On Thu, May 3, 2018 at 4:37 PM, Dan Rae  wrote:

> On 5/3/2018 7:38 AM, Adrian Godwin wrote:
>
>> What sort of heatsink does it need ? Do you need the original part or
>> would
>> a lightly-machined generic module do ?
>>
>> At the time, at least in the UK, it was a very common extrusion, often
> used for power supplies etc., and in fact I see two on the back of big
> Astron supplies under my bench.  I had some in my "junk box" that even had
> the mounting holes in the correct places.   If anyone needs it I can take
> photographs of the back of my 9475 with the heatsink fitted.
>
> Dan
>
> ___
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> ailman/listinfo/time-nuts
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>
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Re: [time-nuts] nuts about position (cheap receiver)

[jimlux]

On 5/3/18 8:28 AM, Bob kb8tq wrote:

Hi

If you have a very good survey grade receiver and take a long enough data set, 
yes you can
watch your location drift in some parts of the world. In most locations, fixes 
a few years apart
would be a better bet.

Indeed this does get a bit far from the world of timing …… The distances 
involved are nasty
small. Even for the location of your telescope when doing astronomical timing 
observations,
they are unlikely to matter on a yearly basis. At some point the error is “to 
small to matter” ….

Bob



Hit send too quick..

But more realistically, this is kind of a time-nutty sort of goal - to 
be able to make measurements to a precision where you can match your 
measurements to a nearby geodetic station with "official" measurements.


All the usual time measurement with GPS issues come into it - multipath, 
the diurnal variations, solid earth tides.


It's what everyone says - getting to meters or 10s of ns - easy - 
getting to tenths of ns or cm, significantly harder.

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Re: [time-nuts] Racal 9475 Rubidium

[Dan Rae]

On 5/3/2018 7:38 AM, Adrian Godwin wrote:

What sort of heatsink does it need ? Do you need the original part or would
a lightly-machined generic module do ?

At the time, at least in the UK, it was a very common extrusion, often 
used for power supplies etc., and in fact I see two on the back of big 
Astron supplies under my bench.  I had some in my "junk box" that even 
had the mounting holes in the correct places.   If anyone needs it I can 
take photographs of the back of my 9475 with the heatsink fitted.


Dan
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Re: [time-nuts] nuts about position (cheap receiver)

[jimlux]

On 5/3/18 8:28 AM, Bob kb8tq wrote:

Hi

If you have a very good survey grade receiver and take a long enough data set, 
yes you can
watch your location drift in some parts of the world. In most locations, fixes 
a few years apart
would be a better bet.

Indeed this does get a bit far from the world of timing …… The distances 
involved are nasty
small. Even for the location of your telescope when doing astronomical timing 
observations,
they are unlikely to matter on a yearly basis. At some point the error is “to 
small to matter” ….

Bob



Unless you live on a plate boundary and have to keep repairing your 
fences and foundations 


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Re: [time-nuts] nuts about position (cheap receiver)

[jimlux]

On 5/3/18 8:09 AM, Bob kb8tq wrote:

Hi

The sites are aimed at improving position information. To the degree that 
having an
accurate location for your antenna improves timing, simply doing that is a step 
forward
for your GPSDO.

Most sites also will give you information that shows the timing solution at a 
given point
in time. To the degree that you can connect that to prior data it could be 
useful. There
are more than a few steps involved in getting this to work.




The JPL processing chain gives not only more accurate positions vs time, 
but also estimates of clock error vs time, if that's in the data stream 
being processed.

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Re: [time-nuts] nuts about position (cheap receiver)

[Bob kb8tq]

Hi

If you have a very good survey grade receiver and take a long enough data set, 
yes you can 
watch your location drift in some parts of the world. In most locations, fixes 
a few years apart
would be a better bet.

Indeed this does get a bit far from the world of timing …… The distances 
involved are nasty
small. Even for the location of your telescope when doing astronomical timing 
observations, 
they are unlikely to matter on a yearly basis. At some point the error is “to 
small to matter” ….

Bob

> On May 3, 2018, at 11:12 AM, Artek Manuals  wrote:
> 
> To further Chris' question if I took data say on the same day every year can 
> I measure which way my tectonic plate is moving and how far?
> 
> -DC
> manu...@artekmanuals.com
> 
> On 5/3/2018 10:17 AM, Chris Caudle wrote:
>> On Wed, May 2, 2018 11:36 pm, Mark Sims wrote:
>>> have Heather do all the receiver configuring, data
>>> capture, and RINEX making...
>> I have been following along with the update messages, and this seems like
>> really cool improvements to the underlying infrastructure pieces that a
>> lot of us use (Lady Heather, support for more GPS  modules, etc.), but I
>> am having trouble putting all the pieces together.
>> 
>> Having submitted the files to some post-processing server, do you only get
>> back information showing your position to some small number of
>> centimeters, or does it send back a stream of values showing the
>> corrections to the full position + time equations at each reading?
>> Can you use this data to go back to, for example, a stream of timestamps
>> and add a correction factor to the timestamps to get improved time
>> accuracy on historical data?
>> 
> 
> -- 
> Dave
> manu...@artekmanuals.com
> www.ArtekManuals.com
> 
> 
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
> 
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Re: [time-nuts] nuts about position (cheap receiver)

[Artek Manuals]

To further Chris' question if I took data say on the same day every year 
can I measure which way my tectonic plate is moving and how far?


-DC
manu...@artekmanuals.com

On 5/3/2018 10:17 AM, Chris Caudle wrote:

On Wed, May 2, 2018 11:36 pm, Mark Sims wrote:

have Heather do all the receiver configuring, data
capture, and RINEX making...

I have been following along with the update messages, and this seems like
really cool improvements to the underlying infrastructure pieces that a
lot of us use (Lady Heather, support for more GPS  modules, etc.), but I
am having trouble putting all the pieces together.

Having submitted the files to some post-processing server, do you only get
back information showing your position to some small number of
centimeters, or does it send back a stream of values showing the
corrections to the full position + time equations at each reading?
Can you use this data to go back to, for example, a stream of timestamps
and add a correction factor to the timestamps to get improved time
accuracy on historical data?



--
Dave
manu...@artekmanuals.com
www.ArtekManuals.com


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

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Re: [time-nuts] nuts about position (cheap receiver)

[Bob kb8tq]

Hi

The sites are aimed at improving position information. To the degree that 
having an
accurate location for your antenna improves timing, simply doing that is a step 
forward
for your GPSDO. 

Most sites also will give you information that shows the timing solution at a 
given point
in time. To the degree that you can connect that to prior data it could be 
useful. There
are more than a few steps involved in getting this to work.

Bob

> On May 3, 2018, at 10:17 AM, Chris Caudle  wrote:
> 
> On Wed, May 2, 2018 11:36 pm, Mark Sims wrote:
>> have Heather do all the receiver configuring, data
>> capture, and RINEX making...
> 
> I have been following along with the update messages, and this seems like
> really cool improvements to the underlying infrastructure pieces that a
> lot of us use (Lady Heather, support for more GPS  modules, etc.), but I
> am having trouble putting all the pieces together.
> 
> Having submitted the files to some post-processing server, do you only get
> back information showing your position to some small number of
> centimeters, or does it send back a stream of values showing the
> corrections to the full position + time equations at each reading?
> Can you use this data to go back to, for example, a stream of timestamps
> and add a correction factor to the timestamps to get improved time
> accuracy on historical data?
> 
> -- 
> Chris Caudle
> 
> 
> 
> 
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Re: [time-nuts] Racal 9475 Rubidium

[Adrian Godwin]

What sort of heatsink does it need ? Do you need the original part or would
a lightly-machined generic module do ?

There are some lovely heatsinks in obsolete (server quality) PCs. Huge
chunks of copper with a fine fin structure and a matched fan. Not all of
them are noisy.


On Thu, May 3, 2018 at 3:13 AM, Roger Tilsley 
wrote:

> Greetings Paul,
>
> The Racal 9475 does have some inherent shortcomings, the principal one is
> due to the power supply and the lack of the purpose-designed heat sink for
> the FRK module.  The unit is built into a “heat-sink case” but to keep the
> FRK base plate within the specified temperature range Racal had to operate
> it from a 23.5 V supply.  The power supply originally had a magnificent
> C-core transformer which produced a rather too-high output voltage
> consequently the raw d.c. supply was rather high.  The main supply voltage
> regulator has a rather weird configuration to facilitate heat sinking the
> pass transistor to the case and this unfortunately precludes using a
> battery back-up.
>
> What Racal overlooked is that with a linear regulator the total amount of
> heat dissipated is sensibly constant so the FRK module dissipates less heat
> than if it were operated at a higher voltage and the PSU pass transistor
> dissipates more heat.  When the case is opened a well-used 9475 usually
> stinks of “hot electronics”!  The problem is compounded by the fact that
> the 5 V logic supply regulator is not adjustable, it is essentially a high
> current follower from the tap of the R62/R63 potential divider across the
> 23.5 V main supply rail.
>
> In my experience, FRK modules produce their best performance when
> operated  from a supply voltage between 27 V and 28 V, selected for
> individual units but 27.6 V is a good starting figure.  At this voltage the
> FRK module needs the special heat sink if operated at high ambient
> temperature.
>
> More recent versions of the 9475 have a good but lower-quality mains
> transformer (perfectly  adequate for its intended purpose) which has a
> lower output voltage and this has mitigated the heat dissipation by the PSU
> pass transistor.
>
> The first thing to do is to monitor the voltage of the 5 V logic supply
> (between TP2 and TP3) and increase the voltage of the 23.5 V main supply
> rail (R39) until the 5 V rail is as much above 5 V as you care to risk for
> the 74-series ICs used.  A safe starting point is 5.2 V but I am wary of
> going too close to 5.5 V.  I have succeeded in getting several recalcitrant
> 9475s working properly by this simple ploy of increasing the supply voltage
> to the FRK module.  In my experience an FRK module operated a with a supply
> voltage lower than 24 V is prone to failing to lock or intermittent locking
> after long use.
>
> The complete cure is to increase the value of R36 to produce 5 V with the
> voltage measured between TP2 and TP3 with the 23.5 V rail wound up to
> between 27 V and 28 V.  This cures the high internal dissipation problem
> and considerably improves the performance of the FRK module but the special
> heat sink is necessary for operation in high ambient temperature or with
> poor ventilation.
>
> There are a few incidental modifications which I like to do to 9475s.
> They were designed when one could have whatever colour of LEDs which one
> wished provided that the colour was red!  I like green LEDs for the
> “normal” situation and with the ready availability of LEDs of different
> colours it is easy to follow the IEC recommendation of orange for “power
> on” and green for “normal situation”.  The “Rb lock” indicator (LP50) is
> already green but it is worth changing the “Power on” indicator (LP51) to
> orange or yellow and I consider it essential to change the “1 MHz”
> indicators (LP52, LP53, and LP54) to green.  If 4 greens are showing the
> unit is locked and the outputs are OK which is perceived with a quick
> glance.
>
> These mods and adjustments are simple and easy to do.  Unfortunately it is
> not nearly so easy to arrange a battery back up facility so it is wise to
> operate the unit from a UPS.  The warm-up frequency drift of an FRK module
> is still detectable 6 weeks or 1000 hours after starting from cold.  The
> 9475 was apparently intended for supplying the 1 MHz reference frequency
> for the synthesisers in Naval communications equipment and its drift is
> sufficiently low for this application within about 2 hours of starting from
> cold, however Time-nuts are more discerning!
>
> At the time of the introduction of the 9475, Racal were the agents for
> Efratom but went to great lengths to save the cost of the special heat sink
> for the FRK module and in my opinion “spoiled the ship for a ha’p’orth of
> tar” (for US readers ha’p’orth is a colloquial expression for a
> “half-pennyworth” of old UK money, about 1/250th of 1 US$ at the present
> rate of exchange).  False economy is also the reason for the 5 V regulator
> in the 9475, at 

Re: [time-nuts] nuts about position (cheap receiver)

[Chris Caudle]

On Wed, May 2, 2018 11:36 pm, Mark Sims wrote:
> have Heather do all the receiver configuring, data
> capture, and RINEX making...

I have been following along with the update messages, and this seems like
really cool improvements to the underlying infrastructure pieces that a
lot of us use (Lady Heather, support for more GPS  modules, etc.), but I
am having trouble putting all the pieces together.

Having submitted the files to some post-processing server, do you only get
back information showing your position to some small number of
centimeters, or does it send back a stream of values showing the
corrections to the full position + time equations at each reading?
Can you use this data to go back to, for example, a stream of timestamps
and add a correction factor to the timestamps to get improved time
accuracy on historical data?

-- 
Chris Caudle




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Re: [time-nuts] nuts about position (cheap receiver)

[Bob kb8tq]

Hi

Thank goodness it now is almost all self contained. Typing three or for lines 
of a script is *so* last century :)

Sounds very cool !! 

LH continues to do amazing things. She is an impressive lady. Do you ever have 
time to sleep?

My guess is that some sort of write up for doing the submittal to each of the 
“likely victim” agencies will be 
needed. Then of course there is the data reduction and plotting on the returned 
file …… hmmm …… :) 

Bob

> On May 3, 2018, at 3:56 AM, Mark Sims  wrote:
> 
> Woohoo! Success!I sent a RINEX 2.10 formatted .obs file generated by 
> Heather from a Ublox 5 to Canada for post-processing.   The results matched 
> those from RTKLIB processing to within 1mm.  Oh, and on noth cases the 
> post-processing used the "emu" orbit info.
> 
> I haven't heard back from Australia, but I think the file that I sent down 
> under has some duplicate data block errors.
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[time-nuts] nuts about position (cheap receiver)

[Mark Sims]

Woohoo! Success!I sent a RINEX 2.10 formatted .obs file generated by 
Heather from a Ublox 5 to Canada for post-processing.   The results matched 
those from RTKLIB processing to within 1mm.  Oh, and on noth cases the 
post-processing used the "emu" orbit info.

 I haven't heard back from Australia, but I think the file that I sent down 
under has some duplicate data block errors.
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