A new commercial server - the LeoNTP Networked Time Server - is now 
available:

     "LeoNTP is a Stratum 1 time server with GPS synchronised clock 
source designed from the ground up with the sole purpose of providing a 
cost effective but highly accurate and extremely high performing 
networked time server. Extremely easy to setup and configurable with 
flexible power options USB/PoE (802.3af) it can provide accurate 
synchronised time for your LAN, WAN, CCTV, PLC, Telephone systems or 
anywhere accurate standalone time is required."

 
https://store.uputronics.com/index.php?route=product/product&product_id=92&search=ntp

I had the chance to test one of these and it seems to work very well, 
including over a GPS outage of several hours.

-- 
Cheers,
David
Web: http://www.satsignal.eu

David Taylor <david-taylor@blueyonder.co.uk.invalid> wrote:
> A new commercial server - the LeoNTP Networked Time Server - is now 
> available:
>
>      "LeoNTP is a Stratum 1 time server with GPS synchronised clock 
> source designed from the ground up with the sole purpose of providing a 
> cost effective but highly accurate and extremely high performing 
> networked time server. Extremely easy to setup and configurable with 
> flexible power options USB/PoE (802.3af) it can provide accurate 
> synchronised time for your LAN, WAN, CCTV, PLC, Telephone systems or 
> anywhere accurate standalone time is required."
>
>  
> https://store.uputronics.com/index.php?route=product/product&product_id=92&search=ntp
>
> I had the chance to test one of these and it seems to work very well, 
> including over a GPS outage of several hours.

Did you monitor the stability of the 10 MHz output?
Do you know that type of oscillator it uses internally?

On 22/07/2016 12:17, Rob wrote:
[]
> Did you monitor the stability of the 10 MHz output?
> Do you know that type of oscillator it uses internally?

I compared the 10 MHz with another couple of sources (one 10 MHz and one 
5 MHz) and it seemed stable.  I didn't do a "time-nuts" measurement (I 
don't have the kit in any case).  There were no obvious jumps or jitters.

I didn't take it apart nor do I have a circuit diagram, and I don't know 
what if uses internally.  It's certainly /not/ the direct output of a 
ublox module.  Perhaps it's similar to their frequency source product, 
but I don't know.  This page has some phase noise measurements for that 
product:

 
http://www.leobodnar.com/shop/index.php?main_page=product_info&products_id=234

-- 
Cheers,
David
Web: http://www.satsignal.eu

David Taylor <david-taylor@blueyonder.co.uk.invalid> wrote:
> On 22/07/2016 12:17, Rob wrote:
> []
>> Did you monitor the stability of the 10 MHz output?
>> Do you know that type of oscillator it uses internally?
>
> I compared the 10 MHz with another couple of sources (one 10 MHz and one 
> 5 MHz) and it seemed stable.  I didn't do a "time-nuts" measurement (I 
> don't have the kit in any case).  There were no obvious jumps or jitters.
>
> I didn't take it apart nor do I have a circuit diagram, and I don't know 
> what if uses internally.  It's certainly /not/ the direct output of a 
> ublox module.  Perhaps it's similar to their frequency source product, 
> but I don't know.  This page has some phase noise measurements for that 
> product:
>
>  
> http://www.leobodnar.com/shop/index.php?main_page=product_info&products_id=234

Ah that looks very interesting... it is something that I require for
a diversity transmit project.  That requires PPS as well, but that can
probably be added to the freq reference product.
(the reverse is usually not so easy)

I would be interested in how the 10 MHz looks when put on an X/Y scope
with a freerunning reference (like a rubidium or cesium reference) on
the other channel.  I.e. does it "wander around" the desired frequency
in a certain hopping pattern.  That is often the case, especially when
the D/A converter used to steer the oscillator does not have enough
bits.

On 22/07/2016 17:39, Rob wrote:
> David Taylor <david-taylor@blueyonder.co.uk.invalid> wrote:
[]
>> http://www.leobodnar.com/shop/index.php?main_page=product_info&products_id=234
>
> Ah that looks very interesting... it is something that I require for
> a diversity transmit project.  That requires PPS as well, but that can
> probably be added to the freq reference product.
> (the reverse is usually not so easy)
>
> I would be interested in how the 10 MHz looks when put on an X/Y scope
> with a freerunning reference (like a rubidium or cesium reference) on
> the other channel.  I.e. does it "wander around" the desired frequency
> in a certain hopping pattern.  That is often the case, especially when
> the D/A converter used to steer the oscillator does not have enough
> bits.

The 10 MHz output from both products is a CMOS level square wave (i.e. 
~0 to 3.3V_ and drives an Airspy receiver directly.  They'll supply the 
required lead as well (at cost).  I don't have a free-running reference 
to compare against, I'm afraid, but I appreciate why you ask.

-- 
Cheers,
David
Web: http://www.satsignal.eu

David Taylor <david-taylor@blueyonder.co.uk.invalid> wrote:
> On 22/07/2016 17:39, Rob wrote:
>> David Taylor <david-taylor@blueyonder.co.uk.invalid> wrote:
> []
>>> http://www.leobodnar.com/shop/index.php?main_page=product_info&products_id=234
>>
>> Ah that looks very interesting... it is something that I require for
>> a diversity transmit project.  That requires PPS as well, but that can
>> probably be added to the freq reference product.
>> (the reverse is usually not so easy)
>>
>> I would be interested in how the 10 MHz looks when put on an X/Y scope
>> with a freerunning reference (like a rubidium or cesium reference) on
>> the other channel.  I.e. does it "wander around" the desired frequency
>> in a certain hopping pattern.  That is often the case, especially when
>> the D/A converter used to steer the oscillator does not have enough
>> bits.
>
> The 10 MHz output from both products is a CMOS level square wave (i.e. 
> ~0 to 3.3V_ and drives an Airspy receiver directly.  They'll supply the 
> required lead as well (at cost).  I don't have a free-running reference 
> to compare against, I'm afraid, but I appreciate why you ask.

I have sent a mail to the maker of those devices, thank you for the
hint about those products!