GPSDO source in Europe?

[daloev]

A product at my workplace uses a GPSDO as a timing source for White Rabbit equipment. We are expanding it to Germany, and I am looking for a good GPSDO we can use. We have used a Trimble Thunderbolt E so far at the US installations, but it is difficult to find another. Trimble says they are working on an updated multi-GNSS Thunderbolt, and apparently the company is just letting the stock of Thunderbolt Es run out, and we haven't found any.

I was wondering if people in this forum could point me to good GPSDO sources in Europe? We need a reliable commercial product, and if we can purchase from a European, or even German source, it is likely to save us shipping and import cost and time.

[thermistor-guy]

Furuno (Japan) GPS products are available in Europe. You could look at its product range, as a starting point.

[Detlev]

ask Meinberg. they mainly produce time systems. They have been on the market for a long time (I bought my first PCM radio remote control for model aircraft there 40 years ago).

https://www.meinberg.de/

[doktor pyta]

https://dxpatrol.pt/produto/gpsdo/

they are from Portugal

[jonpaul]

Leo Bodnar GPS DSO UK
£ 110..165
http://www.leobodnar.com/shop/index.php?main_page=index&cPath=107
excellent units highly recommended

j

[daloev]

Thanks for the pointers. Just today I received a (previously ordered) Leo Bodnar unit to try.

[Wallace Gasiewicz]

Hard to beat Leo
I put together a GSPDO from junk parts and still had over $50 bucks of parts that I had to buy.....
Leo gets my vote.

[nctnico]

You could look at Septentrio (located in Belgium); these guys seem to make the more serious stuff.

[Alex Nikitin]

I'm a (very satisfied) user of Leo Bodnar Mini GPS Clock for over a year. There is one particular feature of this unit that you might need to take into account. The Mini GPS Clock uses a TCXO as the controlled clock, plus the unit gets quite warm to touch. As a result, a sudden change in the case temperature (if you hold the unit in your hand, for example) would result in a frequency deviation. On the graph below is the result for my own unit, held by hand for ~2min (till the frequency came back to 10MHz) and then released. As you may see, the frequency change is about -1ppb (Mini GPS Clock is used as a reference for HP5386A, measuring the OCXO frequency, so a positive change reflects a lower frequency from Mini).

Cheers

Alex

[bingo600]

Not Europe, but US.

Jackson Lab is worth looking at, for a Tbolt replacement
https://www.jackson-labs.com/index.php/products

/Bingo

[daloev]

I had not read about the temperature sensitivity of the Leo Bodnar. I am very glad to know that because it means it wouldn't work for our purpose. I need the stability over a long period of time in spite of minor temperature variations. It will be in a data center so the temperature will be quite stable, but we wouldn't want, for example, someone working on other equipment in the rack to cause a deviation.

[J-R]

Concerned about stability but also want to be holding stuff in your hands?  In the Metrology thread?  Yikes...

The Leo units are tiny, I would find a 1U rack mount enclosure and put it inside to keep paws and breezes away from it.

[mendip_discovery]

I had not read about the temperature sensitivity of the Leo Bodnar. I am very glad to know that because it means it wouldn't work for our purpose. I need the stability over a long period of time in spite of minor temperature variations. It will be in a data center so the temperature will be quite stable, but we wouldn't want, for example, someone working on other equipment in the rack to cause a deviation.

That temp rise (~10°C) caused a 1 ppb change, do you how small of a movement that is? How well behaved are your other units? Just looking at uncertainty from another lab 2.1ppb, I would say it's not unexpected for any unit to drift with temp changes.

[Alex Nikitin]

Yes, only a fast temperature change creates a variation, if the case is protected from air movements and hands, as J-R suggested, it should not be a problem. Slow temperature changes (more than 1min per degree) should be fully compensated by the control loop.

Cheers

Alex

[nctnico]

I had not read about the temperature sensitivity of the Leo Bodnar. I am very glad to know that because it means it wouldn't work for our purpose. I need the stability over a long period of time in spite of minor temperature variations. It will be in a data center so the temperature will be quite stable, but we wouldn't want, for example, someone working on other equipment in the rack to cause a deviation.

I hope you realise that you'll need something like a Rb clock tied to the GPS receiver to get any form of long term stability? The typical, OCXO based GPSDOs will wander around +/-50ns over the period of 24 hours. The Trimble unit you mentioned earlier is no exception. A Rubidium clock (+ cleanup oscillator to get rid of the short term drift / phase noise of a Rb clock) can offer better performance. If you need even better stability, then Cesium is the way to go.