-------- ew via time-nuts writes: > In 1973 I moved for TI to Dallas and had a 20 foot hole drilled to place my > Sulzer One alternate.. Today I monitor my lab closely to better understand > what to do. The monitor is placed on the top of the HP5065A[...] When we built our new house I wanted to build some kind of "clock vault", but however I looked at it, it was either far too expensive or impossible to get planning permission for due to the ground water protection zoning. I later talked to a geologist who knows the Danish underground well, and he estimated I would have needed to drill to at least 25m depth to escape seasonal temperature-changes and cited a research paper from the 1950'ies where the did precisely that experiment. He also mentioned something I had not thought about my self: The ø=15cm end-capped dry steel-pipe I was dreaming of would have been subject to a LOT of upward boyancy force. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.

-------- shouldbe q931 writes: > > Apart from the entire "get electronics wet" thing, water would have > > been near perfect. > > There are alternatives to water... > https://www.3m.co.uk/3M/en_GB/novec-uk/applications/immersion-cooling/ For very, very specific use-cases, yes. I have hard time seeing anybody dunk their OCXO or Rb... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.

I received one of these thunderbolts. It seems to work (currently handicapped by an inadequate antenna) and is labelled P/N 48050-61 D/C 0331 on the outside. The firmware is 3.00 and the OCXO labelled 37265 10.000000 MHz B11859-17495 0310. On Sat, Sep 12, 2020 at 10:43 PM Adrian Godwin <artgodwin@gmail.com> wrote: > Thanks! > > The one I've seen pictured most often comes in a (I think) slightly lower > gold-coloured (alocromed) case. > e.g. http://www.sydneystormcity.com/TrimbleThunderboltGPS.jpg > Is that any different ? > > I did order the one from my link so will report on any markings. The > vendor mentioned part 48050-61 but as you say, that seems to be common to > all of them. > > > On Sat, Sep 12, 2020 at 10:14 PM Bob kb8tq <kb8tq@n1k.org> wrote: > >> Hi >> >> The unit your link points to *is* the “classic” TBolt that showed up in >> volume a bit >> over a decade ago. That one is packaged with a (noisy) switching power >> supply. >> >> There is no easy way to tell what era it is from. Indeed if it is from >> the 1990’s the >> OCXO will not be quite as good as what’s in one from > 2002. Since the >> unit normally >> operates locked, that’s not a real big deal. >> >> Since Trimble used “Thunderbolt” for a whole line of parts *and* was not >> very good >> at labeling devices, there is no easy way to refer to this or that >> specific device. That >> makes coming up with a list of units a bit hard. For example - what’s the >> model number >> of the part in that eBay listing ? ( No I don’t know either …. :) ). >> >> Bob >> >> > On Sep 12, 2020, at 12:28 PM, Adrian Godwin <artgodwin@gmail.com> >> wrote: >> > >> > I've been looking for a thunderbolt for a while, mostly because they're >> > such a benchmark within this group. I missed the period when they were >> more >> > commonly available and have mostly found ones that were a lot more >> > expensive, or had a large delivery cost due to being in Australia. >> > >> > Some cheaper examples turned up on UK ebay. These aren't the classic >> > time-nuts ones but presumably look fairly similar to Lady Heather. >> > >> > https://www.ebay.co.uk/itm/154078750287 >> > >> > I haven't been able to find a comparison of the various thunderbolt >> models. >> > Is there a description somewhere ? I've found a few hints about this >> one - >> > I think it's a single 48V supply and possibly a lower-quality OCXO. >> > >> > On Sat, Sep 12, 2020 at 5:14 PM Kevin Schuchmann <kschuchm@gmail.com> >> wrote: >> > >> >> Matthias, >> >> You are correct, having spent hours looking at all the stable areas >> >> and cooling and heating the gpsdo I find that when it reports that it >> is >> >> 116.25 F then it is stable. >> >> So now I guess I need to figure out why it is so picky. I will measure >> >> the current draw from a cold start and see if I see the oven warming up >> >> and then stabilizing and then heat and cool it and see how it reacts, >> >> and also look at the electronics and see if an area is overly sensitive >> >> to temperature. >> >> >> >> Thanks >> >> Kevin >> >> >> >> >> >> On 9/11/2020 2:26 AM, Matthias Welwarsky wrote: >> >>> On Freitag, 11. September 2020 01:08:09 CEST Kevin Schuchmann wrote: >> >>>> Guess my image didn't make it, I will add it as an attachment this >> time. >> >>> The temperature curve seems to show some correlation to what is >> >> happening with >> >>> the DAC. Seems that the DAC and OSC jumps are mostly during periods of >> >> some >> >>> thermal perturbation. >> >>> >> >>> Regards, >> >>> Matthias >> >>> >> >>> >> >>> >> >>> _______________________________________________ >> >>> time-nuts mailing list -- time-nuts@lists.febo.com >> >>> To unsubscribe, go to >> >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> >>> and follow the instructions there. >> >> >> >> >> >> _______________________________________________ >> >> time-nuts mailing list -- time-nuts@lists.febo.com >> >> To unsubscribe, go to >> >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> >> and follow the instructions there. >> >> >> > _______________________________________________ >> > time-nuts mailing list -- time-nuts@lists.febo.com >> > To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> > and follow the instructions there. >> >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com >> and follow the instructions there. >> >