Re: [time-nuts] UBLOX LEA-5T Programming?

[Hal Murray]

kb...@n1k.org said:
> A $25 Ref-0 with the same GPS and a (now) documented MCU will do the same
> thing as any other GPSDO.

Does anybody know if the Ref-0 expects a clean PPS from the Ref-1 OCXO, or is 
it happy with what comes out of a typical GPS unit?



-- 
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Bob Camp]

Hi

It’s “happy” either way (as in, it will accept the pulse). The stability will 
be degraded due
to hanging bridges if you don’t have sawtooth correction. 

Bob

> On Oct 12, 2015, at 6:13 PM, Hal Murray  wrote:
> 
> 
> kb...@n1k.org said:
>> A $25 Ref-0 with the same GPS and a (now) documented MCU will do the same
>> thing as any other GPSDO.
> 
> Does anybody know if the Ref-0 expects a clean PPS from the Ref-1 OCXO, or is 
> it happy with what comes out of a typical GPS unit?
> 
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Daniel Watson]

Hi,

The REF-0 will accept a PPS signal from a non-timing GPS. I use the u-blox 
NEO-6M for a lot of my testing. That module can be had in the $12 range online. 
I have also gotten the REF-0 to lock to a Venus GPS and an FE-5680B rubidium 
standard.

Of course, using a less stable PPS signal will give you less performance out of 
the REF-0.

I have some information about operating the REF-0 standalone documented on my 
blog:

http://syncchannel.blogspot.com

Dan

> On Oct 12, 2015, at 6:13 PM, Hal Murray  wrote:
> 
> 
> kb...@n1k.org said:
>> A $25 Ref-0 with the same GPS and a (now) documented MCU will do the same
>> thing as any other GPSDO.
> 
> Does anybody know if the Ref-0 expects a clean PPS from the Ref-1 OCXO, or is 
> it happy with what comes out of a typical GPS unit?
> 
> 
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Clint Jay]

I'd second that,  sounds interesting and plenty of accuracy for the project
I'm thinking of.
On 10 Oct 2015 15:00, "Alex Pummer"  wrote:

> Hi Bert,
> where could I get more inf on on that project?
> 73
> KJ6UHN
> Alex
>
> On 10/10/2015 4:23 AM, Bert Kehren via time-nuts wrote:
>
>> We did a GPS PLL using ublox M7 not for time nuts but for Hams no u
>> processors, simple to build  with readily available parts with
>> performance  of 1
>> E-10.. Hams still have get to gether and it would make sense to order the
>> parts. Boards would be less than $ 2 in quantity 10.  5X5 cm board can
>> also
>> work with other VCXO's.
>> Data is attached
>> Bert Kehren
>>
>>
>>
>>
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Alex Pummer]

Hi Bert,
where could I get more inf on on that project?
73
KJ6UHN
Alex

On 10/10/2015 4:23 AM, Bert Kehren via time-nuts wrote:

We did a GPS PLL using ublox M7 not for time nuts but for Hams no u
processors, simple to build  with readily available parts with performance  of 1
E-10.. Hams still have get to gether and it would make sense to order the
parts. Boards would be less than $ 2 in quantity 10.  5X5 cm board can also
work with other VCXO's.
Data is attached
Bert Kehren
  
  





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Re: [time-nuts] UBLOX LEA-5T Programming?

[Dave Martindale]

(Long-term members of the list can skip this; you've seen it many times 
before.  But it sounds like Clint is new, and could use some basic 
explanation.  I was in his position once too).


It sounds like you are assuming that the GPS receiver's internal oscillator is 
locked to GPS time.  In most cases, it isn't - it's a free-running local 
oscillator.  So its frequency isn't terribly accurate.  The GPS receiver, as 
part of its operation, can determine what the local clock frequency is and 
compensate for it.  For the 1 PPS output, the receiver can calculate which 
local clock edge is closest to being the correct location for the next 1 PPS 
pulse, and arranges to change the output state at that time.  But the divisor 
between the internal clock and the 1 PPS output is not constant - it is 
adjusted as necessary to place the 1 PPS as close as possible to the correct time.


For example, suppose the local oscillator is nominally 10 MHz, but it is 
actually 10 PPB fast.  If it was simply divided by 1e7 to get the 1 PPS, the 1 
PPS would also be 10 PPB fast.  So the GPS receiver will arrange to (on 
average) divide by 10,000,000 for 9 seconds out of every 10, but divide by 
10,000,001 every 10th second.  This slows the PPS, on average, by one extra 
oscillator cycle in every 100 million, compensating for the long-term error.  
But now some "1 PPS" periods are actually 100 ns longer than others.  The very 
best the GPS receiver can do at keeping the 1 PPS "on time" as well as "on 
frequency" is to always place the 1 PPS somewhere within 50 ns of the correct 
time.  With this example, the error will drift from 50 ns late to 50 ns early 
over a span of 10 seconds, then abruptly jump to 50 ns late again due to the 
extra-cycle 1 PPS period.  So the time error looks like a sawtooth when graphed.


If you have a timing-grade GPS, the receiver will generally tell you the 
residual error of each 1 PPS pulse, and you can compensate for that when 
comparing an external oscillator to the 1 PPS output. Essentially, it gives 
you a timing reference with a somewhat-random error, but it tells you the 
amount of the error, so you can subtract it out of your calculations.  That's 
easy if you're using a digital PLL to lock another oscillator to the 
(corrected) 1 PPS.  Someone was even talking about designing a delay line to 
remove the sawtooth error from the 1 PPS in hardware.  If you don't do one of 
these things, the 1 PPS output has a lot of jitter.  (And it doesn't 
necessarily average out in 10 seconds, like in the example above. If the local 
oscillator is close to the correct frequency, you can get 1 PPS outputs that 
are on one side or the other of "correct" for hundreds or thousands of 
seconds.  The phenomenon is called "hanging bridges" from the way they look on 
a graph).


- Dave

On 09/10/2015 10:16, Clint Jay wrote:

I am still learning and want to understand, if the PPS is good then why is
the programmable output bad, as I understand it thus far, the PPS is
derived from the same clock source or have I got that badly wrong?




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Re: [time-nuts] UBLOX LEA-5T Programming?

[Bert Kehren via time-nuts]

We did a GPS PLL using ublox M7 not for time nuts but for Hams no u  
processors, simple to build  with readily available parts with performance  of 
1 
E-10.. Hams still have get to gether and it would make sense to order the  
parts. Boards would be less than $ 2 in quantity 10.  5X5 cm board can also  
work with other VCXO's.
Data is attached
Bert Kehren
 
 




Morion_PLL_2-1.xls
Description: Binary data
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Bob Camp]

Hi

The PPS out of the GPS has a number of issues short term. Without sawtooth 
correction it likely is hopping and bopping 5 or 10 ns each second. Looked at as
frequency, the 1 Hz is +/- many ppb. 

The “frequency” output inherits this problem and adds the issues associated 
with pulse
drop frequency synthesis. More or less 10 MHz is a 16 MHz pulse train with 6 
our of 16 
edges dropped out. That does not give you a clean spectrum or a predictable 
signal. 

Combine these two things and you have a signal that most PLL chips will be a 
bit bothered by
*and* a reference that is much less stable than the OCXO. The answer is to 
stretch out the 
comparison process to 100’s of seconds and to use sawtooth correction. Both of 
these things
are easily done with a  < $2 MCU. The gotcha is that you need code to go with 
it. 

A $25 Ref-0 with the same GPS and a (now) documented MCU will do the same thing 
as
any other GPSDO. That sort of sets an upper limit on how much you probably 
should spend
on this sort of thing. That’s not to say that similar logic *does* put an upper 
limit, as I’ve proven on a
large number of projects I’ve done …..

Bob

> On Oct 9, 2015, at 10:16 AM, Clint Jay  wrote:
> 
> I am still learning and want to understand, if the PPS is good then why is
> the programmable output bad, as I understand it thus far, the PPS is
> derived from the same clock source or have I got that badly wrong?
> 
> On 9 October 2015 at 12:16, Bob Camp  wrote:
> 
>> Hi
>> 
>> Doing a GPSDO by locking to the awful 10 MHz output from any of these GPS
>> modules
>> is not going to work very well. Given the very long time constants
>> involved in a GPSDO
>> control loop, doing it without code is going to be pretty difficult.
>> 
>> A much easier approach:
>> 
>> Grab the GPS PPS and a scope. Use it to set the Lucent boxes on frequency.
>> Repeat the process
>> once a week.  The direct lock will flop around by (likely many) ppb. Your
>> manual set will probably keep it
>> under 1 ppb for a week.
>> 
>> Bob
>> 
>>> On Oct 9, 2015, at 1:39 AM, Perry Sandeen via time-nuts <
>> time-nuts@febo.com> wrote:
>>> 
>>> Hi,
>>> I have six of the older style (anodized solid aluminum case) Lucent
>> crystal oscillators that I’d like to turn into simple 10 MHZ output
>> GPSDO’s. I have some salvaged HP cases so I can have a linear PS and all
>> other stuff in one package.
>>> I’ve found two different choices of GPS relatively low cost units on
>> Ebay.
>>> One is a LUCENT M12+ GPS Timing Receiver W/100 Hz output  for  $19.99
>> Item 171886538138.
>>> The other is a UBLOX LEA-5T GPS module dev board 1PPS /USB/RS232/ntp ser
>> with two 1 PPS outputs for $49.90. Item 251785217093.
>>> IIRC, one output of a Ublox can be set to a 10 MHz.
>>> Can this model be set to have a 10 MHz output and is it easily done from
>> a PC? I have no coding ability.
>>> For more money I’d get a simpler phase detector circuit, which is all
>> I’m looking for. For less money I’d have to build more circuitry.
>>> A factor I don’t know is if the ublox is that much better/newer to
>> justify the price difference.
>>> I already have packed away two Oncore units with either a 1 KHz or 10
>> KHz output.
>>> Suggestions welcomed.
>>> Regards,
>>> Perrier
>>> ___
>>> time-nuts mailing list -- time-nuts@febo.com
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>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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>> 
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>> and follow the instructions there.
>> 
> 
> 
> 
> -- 
> Clint.
> 
> *No trees were harmed in the sending of this mail. However, a large number
> of electrons were greatly inconvenienced.*
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[time-nuts] UBLOX LEA-5T Programming?

[Perry Sandeen via time-nuts]

Hi,
I have six of the older style (anodized solid aluminum case) Lucent crystal 
oscillators that I’d like to turn into simple 10 MHZ output GPSDO’s. I have 
some salvaged HP cases so I can have a linear PS and all other stuff in one 
package.
I’ve found two different choices of GPS relatively low cost units on Ebay. 
One is a LUCENT M12+ GPS Timing Receiver W/100 Hz output  for  $19.99 Item 
171886538138.
The other is a UBLOX LEA-5T GPS module dev board 1PPS /USB/RS232/ntp ser with 
two 1 PPS outputs for $49.90. Item 251785217093.
IIRC, one output of a Ublox can be set to a 10 MHz.
Can this model be set to have a 10 MHz output and is it easily done from a PC? 
I have no coding ability.
For more money I’d get a simpler phase detector circuit, which is all I’m 
looking for. For less money I’d have to build more circuitry.
A factor I don’t know is if the ublox is that much better/newer to justify the 
price difference.
I already have packed away two Oncore units with either a 1 KHz or 10 KHz 
output.
Suggestions welcomed.
 Regards,
Perrier
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Mike Cook]

> Le 9 oct. 2015 à 16:16, Clint Jay  a écrit :
> 
> I am still learning and want to understand, if the PPS is good then why is
> the programmable output bad, as I understand it thus far, the PPS is
> derived from the same clock source or have I got that badly wrong?

Yes, the same clock, BUT the output signal rising edge is aligned with the 
nearest internal clock pulse leading edge, as is the 1PPS output, which gives 
rise to something called quantization error. If the configured frequency is an 
integral division of the cpu clock, then OK, but if it is not then this error 
is apparent. IIRC,  the on board cpu oscillator is 48MHz, and so an 8MHz output 
will be OK, but 10MHz does not divide evenly into 48Mz so you get significant 
jitter.  

There is a nice Ublox doc «  Timing_AppNote_(GPS.G6-X-11007).pdf » illustrating 
this. I don’t know if there was one issued for the 5T receiver, but the 
principle is the 
same. Google should find it.


> 
> On 9 October 2015 at 12:16, Bob Camp  wrote:
> 
>> Hi
>> 
>> Doing a GPSDO by locking to the awful 10 MHz output from any of these GPS
>> modules
>> is not going to work very well. Given the very long time constants
>> involved in a GPSDO
>> control loop, doing it without code is going to be pretty difficult.
>> 
>> A much easier approach:
>> 
>> Grab the GPS PPS and a scope. Use it to set the Lucent boxes on frequency.
>> Repeat the process
>> once a week.  The direct lock will flop around by (likely many) ppb. Your
>> manual set will probably keep it
>> under 1 ppb for a week.
>> 
>> Bob
>> 
>>> On Oct 9, 2015, at 1:39 AM, Perry Sandeen via time-nuts <
>> time-nuts@febo.com> wrote:
>>> 
>>> Hi,
>>> I have six of the older style (anodized solid aluminum case) Lucent
>> crystal oscillators that I’d like to turn into simple 10 MHZ output
>> GPSDO’s. I have some salvaged HP cases so I can have a linear PS and all
>> other stuff in one package.
>>> I’ve found two different choices of GPS relatively low cost units on
>> Ebay.
>>> One is a LUCENT M12+ GPS Timing Receiver W/100 Hz output  for  $19.99
>> Item 171886538138.
>>> The other is a UBLOX LEA-5T GPS module dev board 1PPS /USB/RS232/ntp ser
>> with two 1 PPS outputs for $49.90. Item 251785217093.
>>> IIRC, one output of a Ublox can be set to a 10 MHz.
>>> Can this model be set to have a 10 MHz output and is it easily done from
>> a PC? I have no coding ability.
>>> For more money I’d get a simpler phase detector circuit, which is all
>> I’m looking for. For less money I’d have to build more circuitry.
>>> A factor I don’t know is if the ublox is that much better/newer to
>> justify the price difference.
>>> I already have packed away two Oncore units with either a 1 KHz or 10
>> KHz output.
>>> Suggestions welcomed.
>>> Regards,
>>> Perrier
>>> ___
>>> time-nuts mailing list -- time-nuts@febo.com
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>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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>> 
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>> and follow the instructions there.
>> 
> 
> 
> 
> -- 
> Clint.
> 
> *No trees were harmed in the sending of this mail. However, a large number
> of electrons were greatly inconvenienced.*
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"The main function of a modern police force is filling in forms."
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Bert Kehren via time-nuts]

The 1 pps and the output frequencies are all derived from the same XO in  
the module. Up to 7 the difference in a T is that the saw tooth correction  
factor is brought out for correction purposes . 7 has a much higher XO  
frequency than the 5 so the saw tooth is smaller. So use a ublox 7 if you want  
to do a simple GPSPLL like James Miller described.  If you use the cheaper  M 
version you have to make sure you always have backup power since it does 
not  have a flash memory like the more expensive N version to memorize the  
setting Also stay away from 10 MHz out  better to use 200 or 400 KHz.  We have 
done a GPSPLL with ublox7 and Morion and got very good results. I have a  
board  if interested contact me off list.
Bert Kehren
 
 
In a message dated 10/9/2015 12:03:45 P.M. Eastern Daylight Time,  
cjaysh...@gmail.com writes:

I am  still learning and want to understand, if the PPS is good then why is
the  programmable output bad, as I understand it thus far, the PPS is
derived  from the same clock source or have I got that badly wrong?

On 9 October  2015 at 12:16, Bob Camp  wrote:

>  Hi
>
> Doing a GPSDO by locking to the awful 10 MHz output from  any of these GPS
> modules
> is not going to work very well. Given  the very long time constants
> involved in a GPSDO
> control loop,  doing it without code is going to be pretty difficult.
>
> A much  easier approach:
>
> Grab the GPS PPS and a scope. Use it to set  the Lucent boxes on 
frequency.
> Repeat the process
> once a  week.  The direct lock will flop around by (likely many) ppb.  
Your
> manual set will probably keep it
> under 1 ppb for a  week.
>
> Bob
>
> > On Oct 9, 2015, at 1:39 AM,  Perry Sandeen via time-nuts <
> time-nuts@febo.com> wrote:
>  >
> > Hi,
> > I have six of the older style (anodized  solid aluminum case) Lucent
> crystal oscillators that I’d like to turn  into simple 10 MHZ output
> GPSDO’s. I have some salvaged HP cases so I  can have a linear PS and all
> other stuff in one package.
> >  I’ve found two different choices of GPS relatively low cost units on
>  Ebay.
> > One is a LUCENT M12+ GPS Timing Receiver W/100 Hz  output  for  $19.99
> Item 171886538138.
> > The  other is a UBLOX LEA-5T GPS module dev board 1PPS /USB/RS232/ntp 
ser
>  with two 1 PPS outputs for $49.90. Item 251785217093.
> > IIRC, one  output of a Ublox can be set to a 10 MHz.
> > Can this model be set  to have a 10 MHz output and is it easily done 
from
> a PC? I have no  coding ability.
> > For more money I’d get a simpler phase detector  circuit, which is all
> I’m looking for. For less money I’d have to  build more circuitry.
> > A factor I don’t know is if the ublox is  that much better/newer to
> justify the price difference.
> > I  already have packed away two Oncore units with either a 1 KHz or 10
>  KHz output.
> > Suggestions welcomed.
> >   Regards,
> > Perrier
> >  ___
> > time-nuts mailing  list -- time-nuts@febo.com
> > To unsubscribe, go to
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>



-- 
Clint.

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of electrons  were greatly  inconvenienced.*
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Graham / KE9H]

There is a lot of jitter on a GPS 1 PPS output.
You need a big "flywheel" to smooth out the jitter errors.
GPS modules only have room for small flywheels.
--- Graham


On Fri, Oct 9, 2015 at 9:16 AM, Clint Jay  wrote:

> I am still learning and want to understand, if the PPS is good then why is
> the programmable output bad, as I understand it thus far, the PPS is
> derived from the same clock source or have I got that badly wrong?
>
> On 9 October 2015 at 12:16, Bob Camp  wrote:
>
> > Hi
> >
> > Doing a GPSDO by locking to the awful 10 MHz output from any of these GPS
> > modules
> > is not going to work very well. Given the very long time constants
> > involved in a GPSDO
> > control loop, doing it without code is going to be pretty difficult.
> >
> > A much easier approach:
> >
> > Grab the GPS PPS and a scope. Use it to set the Lucent boxes on
> frequency.
> > Repeat the process
> > once a week.  The direct lock will flop around by (likely many) ppb. Your
> > manual set will probably keep it
> > under 1 ppb for a week.
> >
> > Bob
> >
> > > On Oct 9, 2015, at 1:39 AM, Perry Sandeen via time-nuts <
> > time-nuts@febo.com> wrote:
> > >
> > > Hi,
> > > I have six of the older style (anodized solid aluminum case) Lucent
> > crystal oscillators that I’d like to turn into simple 10 MHZ output
> > GPSDO’s. I have some salvaged HP cases so I can have a linear PS and all
> > other stuff in one package.
> > > I’ve found two different choices of GPS relatively low cost units on
> > Ebay.
> > > One is a LUCENT M12+ GPS Timing Receiver W/100 Hz output  for  $19.99
> > Item 171886538138.
> > > The other is a UBLOX LEA-5T GPS module dev board 1PPS /USB/RS232/ntp
> ser
> > with two 1 PPS outputs for $49.90. Item 251785217093.
> > > IIRC, one output of a Ublox can be set to a 10 MHz.
> > > Can this model be set to have a 10 MHz output and is it easily done
> from
> > a PC? I have no coding ability.
> > > For more money I’d get a simpler phase detector circuit, which is all
> > I’m looking for. For less money I’d have to build more circuitry.
> > > A factor I don’t know is if the ublox is that much better/newer to
> > justify the price difference.
> > > I already have packed away two Oncore units with either a 1 KHz or 10
> > KHz output.
> > > Suggestions welcomed.
> > >  Regards,
> > > Perrier
> > > ___
> > > 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.
> >
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> > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> > and follow the instructions there.
> >
>
>
>
> --
> Clint.
>
> *No trees were harmed in the sending of this mail. However, a large number
> of electrons were greatly inconvenienced.*
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Clint Jay]

I am still learning and want to understand, if the PPS is good then why is
the programmable output bad, as I understand it thus far, the PPS is
derived from the same clock source or have I got that badly wrong?

On 9 October 2015 at 12:16, Bob Camp  wrote:

> Hi
>
> Doing a GPSDO by locking to the awful 10 MHz output from any of these GPS
> modules
> is not going to work very well. Given the very long time constants
> involved in a GPSDO
> control loop, doing it without code is going to be pretty difficult.
>
> A much easier approach:
>
> Grab the GPS PPS and a scope. Use it to set the Lucent boxes on frequency.
> Repeat the process
> once a week.  The direct lock will flop around by (likely many) ppb. Your
> manual set will probably keep it
> under 1 ppb for a week.
>
> Bob
>
> > On Oct 9, 2015, at 1:39 AM, Perry Sandeen via time-nuts <
> time-nuts@febo.com> wrote:
> >
> > Hi,
> > I have six of the older style (anodized solid aluminum case) Lucent
> crystal oscillators that I’d like to turn into simple 10 MHZ output
> GPSDO’s. I have some salvaged HP cases so I can have a linear PS and all
> other stuff in one package.
> > I’ve found two different choices of GPS relatively low cost units on
> Ebay.
> > One is a LUCENT M12+ GPS Timing Receiver W/100 Hz output  for  $19.99
> Item 171886538138.
> > The other is a UBLOX LEA-5T GPS module dev board 1PPS /USB/RS232/ntp ser
> with two 1 PPS outputs for $49.90. Item 251785217093.
> > IIRC, one output of a Ublox can be set to a 10 MHz.
> > Can this model be set to have a 10 MHz output and is it easily done from
> a PC? I have no coding ability.
> > For more money I’d get a simpler phase detector circuit, which is all
> I’m looking for. For less money I’d have to build more circuitry.
> > A factor I don’t know is if the ublox is that much better/newer to
> justify the price difference.
> > I already have packed away two Oncore units with either a 1 KHz or 10
> KHz output.
> > Suggestions welcomed.
> >  Regards,
> > Perrier
> > ___
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-- 
Clint.

*No trees were harmed in the sending of this mail. However, a large number
of electrons were greatly inconvenienced.*
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Re: [time-nuts] UBLOX LEA-5T Programming?

[Bob Camp]

Hi

Doing a GPSDO by locking to the awful 10 MHz output from any of these GPS 
modules
is not going to work very well. Given the very long time constants involved in 
a GPSDO 
control loop, doing it without code is going to be pretty difficult. 

A much easier approach:

Grab the GPS PPS and a scope. Use it to set the Lucent boxes on frequency. 
Repeat the process 
once a week.  The direct lock will flop around by (likely many) ppb. Your 
manual set will probably keep it
under 1 ppb for a week. 

Bob

> On Oct 9, 2015, at 1:39 AM, Perry Sandeen via time-nuts  
> wrote:
> 
> Hi,
> I have six of the older style (anodized solid aluminum case) Lucent crystal 
> oscillators that I’d like to turn into simple 10 MHZ output GPSDO’s. I have 
> some salvaged HP cases so I can have a linear PS and all other stuff in one 
> package.
> I’ve found two different choices of GPS relatively low cost units on Ebay. 
> One is a LUCENT M12+ GPS Timing Receiver W/100 Hz output  for  $19.99 Item 
> 171886538138.
> The other is a UBLOX LEA-5T GPS module dev board 1PPS /USB/RS232/ntp ser with 
> two 1 PPS outputs for $49.90. Item 251785217093.
> IIRC, one output of a Ublox can be set to a 10 MHz.
> Can this model be set to have a 10 MHz output and is it easily done from a 
> PC? I have no coding ability.
> For more money I’d get a simpler phase detector circuit, which is all I’m 
> looking for. For less money I’d have to build more circuitry.
> A factor I don’t know is if the ublox is that much better/newer to justify 
> the price difference.
> I already have packed away two Oncore units with either a 1 KHz or 10 KHz 
> output.
> Suggestions welcomed.
>  Regards,
> Perrier
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> and follow the instructions there.

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