[time-nuts] Re: Raspberry Pi with TimeHat thinks it's 2002!
Newer version works great. Just reflash. It'd be nice if it was as easy as apt get update or yum update but flashing new image works. Bill On Fri, Dec 31, 2021, 6:17 PM John Miller via time-nuts < time-nuts@lists.febo.com> wrote: > Hi Robert! > You almost certainly are still running the older version of GPSD which has > this exact issue. You can manually update GPSD, but the quickest fix for > this is to flash a newer version of the TimeHat image to your SD card. > > You can download that image here: > https://millerjs.org/files/TimeHat32_20211022.img.xz > > To flash it to a microSD card, use balena etcher: > https://www.balena.io/etcher/ > > Feel free to reach out to me directly if you want more one on one help, or > if you want to try updating GPSD on your existing image. > > Regards, > John Miller > j...@millerjs.org > > > On Dec 31, 2021, at 8:10 PM, Robert DiRosario > wrote: > > > > My Raspberry Pi with a TimeHat thinks it's May 18 2002. > > > > When I refresh / reload the web page the time updates fine, but not the > date. > > > > Fix Data > > Fix Type3D Fix > > Fix StatusDGPS Fix > > Time > > UTC2002-05-18T00:47:58.000Z > > Leap Seconds18 > > > > > > Dilution of Precision > > GDOP 1.63 > > HDOP 0.94 > > PDOP 1.44 > > TDOP 0.76 > > XDOP 0.58 > > YDOP 0.74 > > VDOP 1.09 > > > > Error Estimates > > epc 0 m/s > > eph 2.012 m > > eps 0 m/s > > ept0.005 s > > epx 2.173 m > > epy 2.788 m > > epv 2.449 m > > sep 1899.81 m > > ecef pAcc 3.17 m > > ecef vAcc 0.32 m > > > > > > Satellites > > Seen 23 Used 15 > >PRN ElvAzm SNRUsed > > GP1163 105 39 Y > > GP7743 184 30 Y > > GP8819 59 32 Y > > GP131314 289 39 Y > > GP141456 317 30 Y > > GP171743 259 24 Y > > GP191919 248 35 Y > > GP212145 58 44 Y > > GP303061 226 28 Y > > SB1334620 244 30 Y > > SB1385135 223 34 Y > > GL157978 99 39 Y > > GL178166 24 42 Y > > GL188257 223 40 Y > > GL248814 34 29 Y > > GP334 135 0 N > > GP222215 113 16uN > > GP28280 0 35uN > > SB1354823 241 36 N > > GL147826 136 0 N > > GL168036 326 0 N > > GL198312 216 20 N > > GL279166 24 0 N > > > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe > send an email to time-nuts-le...@lists.febo.com > > To unsubscribe, go to and follow the instructions there. > ___ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send > an email to time-nuts-le...@lists.febo.com > To unsubscribe, go to and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Re: Frequency Standard - Where Can I Get One.
There's no substitute for a few good rubidiums. OCXO and Rb are different. It's really hard to beat a really good GNSS diciplined Rb! Extremely good holdover. We're timenuts after all right? Where's the fun if you don't try them all? There isn't any silver bullet or perfect solution but I've found with some good measurement and comparisons you too can be in the search of better and better stability. Half the fun is finding a better OCXO or finding a really stable Rb. Testing them all against each other is part of the journey. Letting timelab run all night every night. Flipping back and forth between graphs. For me it's a hobby but I've gotten many many hours of great happiness from it. The first time I got into 10 ^ -13 how can you explain what that's like? The huge digits on an SR620 you can read from across the room. I guess it's different for each of us but it's something we all share. Bill On Sun, Nov 21, 2021, 1:58 PM Magnus Danielson via time-nuts < time-nuts@lists.febo.com> wrote: > Hi, > > So, on that note. I am surprised that I have not seen popular telecom > rubidiums being reverse-engineered. For instance, the LPRO-101 should > have been reverse-engineered a long time. Some of the circuitry is known > from patents, but those do not build up a complete schematic. I've > considered to do the job, but apparently I have not been able to sit > down and do that particular job either. > > I think the LRPO-101 should not be too much of a challenge. Beyond the > schematic some documentation of the other functions, hints and tips, > etc. that is related should be written up so one approach something > similar to a service manual. > > With enough people contributing, I think it should not be too hard to > collect things. We should be able to provide useful hints and tricks, > such as suitable replacement components etc. > > Cheers, > Magnus > > Den 2021-11-21 kl. 19:45, skrev Bob kb8tq: > > Hi > > > > Well, if I could keep a 5065 running without repairs for more than a > couple years > > I might be more willing to agree with you. What makes the 5065 different > is that you > > have schematics and can do repairs. When the telecom gizmos die, there’s > not much > > to fall back on. They were designed to run a finite amount of time and > then go to the > > scrap heap. > > > > Bob > > > >> On Nov 21, 2021, at 12:03 PM, Skip Withrow > wrote: > >> > >> Hello Time-Nuts, > >> > >> No offense Bob, but I would like to take issue with your statement 'Rb > >> standards have a finite life'. > >> > >> There are time-nuts on this list of every skill and knowledge level > >> and I would like to keep the information as correct as possible. My > >> feeling is this is not a true statement. > >> > >> There is nothing inherent in the design of a rubidium frequency > >> standard that limits its life (unlike cesium). However, there are > >> manufacturing choices that can possibly limit time before failure. > >> > >> First example, of course, is the HP 5065. There are many of us that > >> have units that have been running continuously for close to 50 years. > >> HP made choices in their bulb design that ensures that it runs for a > >> very long time. > >> > >> An opposite example would be the Tracor rubidiums. The lamps in these > >> units were either horribly underfilled, or the glass was very reactive > >> with Rb and almost all suffered from rather early lamp failures. > >> > >> Then, there is the huge mass of telecom rubidiums. As you stated, > >> keeping the base plate at a reasonable temperature goes a LONG way to > >> extended life. Excessive temperature obviously leads to higher > >> component (and sometimes lamp) failure. > >> > >> There are also units that just did not have enough design margin in > >> certain areas. The SRS PRS-10 is one of these where I have seen > >> things go up in smoke in the lamp area. BTW, the HP 5065 can have > >> some issues in this area as well. > >> > >> I'm obviously a big fan of rubidium frequency standards. My advice to > >> newer time-nuts is that you can't go wrong owning one (better long > >> term stability than OCXO, lots less cost and longer life than cesium). > >> > >> I'll get off the soap box now. Thanks for the bandwidth. > >> > >> Skip Withrow > >> ___ > >> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe > send an email to time-nuts-le...@lists.febo.com > >> To unsubscribe, go to and follow the instructions there. > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe > send an email to time-nuts-le...@lists.febo.com > > To unsubscribe, go to and follow the instructions there. > ___ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send > an email to time-nuts-le...@lists.febo.com > To unsubscribe, go to and follow the instructions there.
[time-nuts] Re: Passive Maser teardown
So many layers in there Corby! It's amazing how these things are built! Really cool series to read about. Thanks for the update! I really hope you get this thing going. Best Regards, Bill On Wed, Oct 20, 2021, 11:15 AM wrote: > > Subject: Passive Maser teardown > > Just added "update 5" to http://www.leapsecond.com/maser/ > > It gives details on "digging down" to the cavity of the Maser. > > Cheers! > > Corby > ___ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send > an email to time-nuts-le...@lists.febo.com > To unsubscribe, go to and follow the instructions there. > ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
[time-nuts] Re: Query about List and about 10 MHz Distro
White rabbit seems pretty good for time synced over fiber. PTP with
enhanced stability profile. It's a IEEE standard. It seems to work for
CERN. Lately I've been looking at Cisco devices that can support it. It
whould be nice if I could find hardware that'll support it more easily...
Maybe it'll come soon?
If you need optics I highly recommend AMC optics they'll code (Cisco,
Intel, NetApp) SFP+ and QSFP for any vendor you want. Prices are great and
it's all made the USA no relation to me. I've been getting into 100G
Ethernet over OM4 fiber. The new profile for PTP over fiber is legit.
Bill
On Sat, Aug 28, 2021, 12:04 PM Dana Whitlow wrote:
> I was looking for something similar about 18 months or so ago. Although I
> haven't taken any
> action yet, I concluded that one could do a nice job for under $200 per
> segment, including the
> transmitter and receiver modules and lots of connectorized multimode
> fiber. What I *don't* know
> is what the phase noise performance would be, except that I do know that
> the fiber's VF *is*
> materially influenced by temperature.
>
> I was looking primarily at the HFBR-2416 for the fiber receiver, and the
> HFBR-1412 (standard
> power) or the HFBR-1414 (high power option) for the transmitter Unlike
> most of the available
> models, these are fundamentally analog devices, meaning that you can
> transmit sinewave
> 10 MHz through them. At the time I was looking, Mouser was selling these
> for about $20 each.
>
> See the datasheet at
> https://www.mouser.com/datasheet/2/678/AV02-0176EN_2019-02-15-1827546.pdf
> with particular attention to page 21 regarding the HFBR-2416 receiver.
>
> I was also looking at Fiber Instrument Sales for patch cords. We bought a
> lot of fiber stuff from
> them at Arecibo, and I was always happy with them. See:
>
> https://www.fiberinstrumentsales.com/catalog-cable-assemblies?gclid=Cj0KCQjwvaeJBhCvARIsABgTDM7eNTkP2nQbyFzhcwDE38VnSEP879MBKV1ZyDq2YrnEtOn7_VfzjbkaAtpfEALw_wcB
>
> Somebody had pointed out yet another source of connectorized fibers ("patch
> cords") to me, but I cannot find the name
> at the moment.
>
> Dana K8YUM
>
>
> On Sat, Aug 28, 2021 at 11:52 AM AC0XU (Jim)
> wrote:
>
> > I am hoping that you can help me about a couple of things:
> >
> > 1) My time-nuts summaries sometimes appear unformatted and unreadable.
> All
> > the text from all the postings is crammed together without spacing. How
> can
> > I fix it?
> >
> > 2) I want to distribute 10 MHz references by fiber. There are
> > RF-over-Fiber products available, but too expensive for me (thousands of
> > $$$ per xmit/rcv set). I am thinking that it should be possible to use
> > fiber Ethernet components to do this. I don't mean IEEE 1588 but a much
> > simpler, no-computer-required, solution. Possibly just converting sine
> wave
> > (coax) to square wave (fiber) to sine wave (coax). I am looking for a low
> > cost solution. Any thoughts or recommendations??
> >
> > Thanks!
> >
> > Jim
> > ___
> > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe
> send
> > an email to time-nuts-le...@lists.febo.com
> > To unsubscribe, go to and follow the instructions there.
> >
> ___
> time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send
> an email to time-nuts-le...@lists.febo.com
> To unsubscribe, go to and follow the instructions there.
>
___
time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an
email to time-nuts-le...@lists.febo.com
To unsubscribe, go to and follow the instructions there.
[time-nuts] Re: 2nd Run of TimeHats
I'd be interested in 2 too. Bill On Wed, Apr 28, 2021, 4:10 AM Michael Gindonis wrote: > I would be interested in at least one, perhaps even 2. and perhaps bare > boards. > > Some things that if not already considered, could make it more interesting > than it already is: > > - possibility to have a 26 pin connector instead of the 40 pin connector > would be nice for use on Pi 1B. ( or just an option for unsoldered > connector and one can solder it oneself.) > - bare board with breakout connections for RTC and GPS modules, a > CR2032 holder... this could make the bare board handy as time-nut oriented > protoboard to use with other modules. > - extra pads opposite GPIO side of board to mount a couple extra SMA > connectors. ( using proto space one could add one a buffered PPS out or > other timepulse out ) > - MAX-M8W with active antenna out. > > I have been lurking on this list for a while. A minor upgrade to my low > budget ntp server is long overdue. Have used Aliexpress RTC modules with > the Pi ( with modifications to use a CR2032 safely). I have also had a few > Pis running with nearly 20 year old surplus fastrax GPS modules which > include a patch antenna. Just a protoboard, jumpers, sometimes a backup > battery and some DIP switches for setting modes. I had started a GPS board > design in KiCAD a while ago but got bogged down when trying to layout the > traces for the antenna connector according to the module manufacturer's > recommendations. > > At the moment I just one running GPS ntp server on an old Pi 1B. The module > I use works well most of the day. Having a patch and no external antenna > connector the whole module must be exposed to sunlight. The module doesn't > adjust it's TXCO offset if it doesn't have a GPS fix so it may drift a bit > on sunny days. > > Name/IP AddressNP NR Span Frequency Freq Skew Offset Std > Dev > > == > NMEA8 7 224-17.321 8.039+55ms > 238us > PPS61 36 240 -0.000 0.003 -0ns > 414ns > ftp.mikes.fi 19 13 310m -0.050 0.010 +1718us > 64us > ntp.netnod.se 15 9 241m -0.046 0.044 +1596us > 183us > time.cloudflare.com49 26 13h -0.099 0.013 +2935us > 372us > ivanova.ganneff.de 14 9 224m -0.045 0.025 +3083us > 79us > > Best regards... > > ...Mike > --- > Michael Gindonis > > > > On Mon, Apr 26, 2021 at 7:58 PM John Miller via time-nuts < > time-nuts@lists.febo.com> wrote: > > > Hello everyone, > > > > I’ve seen a number of messages lately that reference the TimeHat boards I > > put together a couple of months ago, with lots of positive feedback, > which > > I really appreciate. The first run of boards I did sold fairly quickly, > and > > based on a number of emails I have gotten lately there seems to be some > > renewed interest. > > > > As such, I’m going to order up another batch of PCBs and parts, but I’d > > like to get an idea of how many I need to order to satisfy current > demand. > > The GPS modules come from China, so there is about a two or three week > wait > > them, so I want to make sure I have enough. > > > > For those not familiar, you can learn more about the TimeHat here: > > https://millerjs.org/timehat > > > > Regards, > > John > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe > send > > an email to time-nuts-le...@lists.febo.com > > To unsubscribe, go to and follow the instructions there. > ___ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send > an email to time-nuts-le...@lists.febo.com > To unsubscribe, go to and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-le...@lists.febo.com To unsubscribe, go to and follow the instructions there.
Re: [time-nuts] Used Hydrogen Maser
Let me know when I can buy one please! I'm not kidding. ;^} Bill in Arizona On Sat, Feb 6, 2021, 1:25 PM Tom Van Baak wrote: > > ptti/1981papers/Vol%2013_30.pdf > > Note the dialog on the last page. Dave Wineland went on to win the 2012 > Nobel prize in Physics: > > > https://www.nist.gov/nist-and-nobel/dave-wineland/person-behind-nobel-prize-dave-wineland > > The first photo is fun, "Before he was a quantum mechanic...". Then > there's this recent press release: > > https://around.uoregon.edu/wineland > > The lovely photo of NBS-6 (NIST cesium clock) comes from: > > https://www.nist.gov/image/img044jpg > > And for a nice trip through the past, including NBS-1 and NIST-7 see: > > https://www.nist.gov/si-redefinition/second/second-past > > /tvb > > > On 2/6/2021 10:05 AM, Attila Kinali wrote: > > Moin, > > > > On Wed, 10 Jul 2019 10:55:07 -0700 > > "Richard (Rick) Karlquist" wrote: > > > >> FWIW, about 20 years ago, Len Cutler and Robin Giffard of 5071A fame > >> built several Hg ion clocks to be shipped to some govt customer I > >> don't remember. One of the clocks was dropped by the shipping company > >> UPS or FedEX) and destroyed. Only then did Len learn that HP was > >> self insured, probably as part of a package deal to get a low > >> corporate shipping rate. HP products were packed extremely well, so > >> the only real risk was the unit getting stolen. I vaguely remember > >> Len saying they were out $10K, which was probably just the cost of > >> parts. Nevertheless, it didn't seem like building an Hg clock was > >> all that big of a project. Way simpler than the 5071A. > >> Now a days, the electronics would be considerably easier and cheaper. > >> The mechanical parts would all be CNC'ed by an online machine shop. > > Magnus just send me out to chase an (unrelated) paper and I stumbled > > over [1] which describes the Hg standard that Cutler & Co built. > > Remembering this discussion I thought it might be interesting to > > some. > > > > > > Attila Kinali > > "Trapped Mercury 199 Ion Frequency Standard", Cutler, > > Giffard, McGuire, PTTI, 1981 > > http://time.kinali.ch/ptti/1981papers/Vol%2013_30.pdf > > > > > ___ > 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.
Re: [time-nuts] Leakage, tinySA
Knock offs is part of the reason I posted the main US distributer earlier. The software is basically open source so anyone could theoretically make one. There's only one original manufacturer though. R Electronics is the only sanctioned US distributer I'm aware of. Also they have the best price in US you can find for obvious reasons. FWIW I don't have spurs at 10MHz. Bill in AZ On Sun, Jan 17, 2021, 5:35 PM Dana Whitlow wrote: > Hi Dan, > > I remember seeing the list of checks to make regarding knockoff clones, > and even remember a few of them: to wit: > > 1. Comes in molded packaging, not poly foam. Check! > 2. Has the internal shielding. Check! > 3. Passes all the self tests, including 7 & 8. Check! > > I had high hopes of moving the birdie off 10 MHz by changing the IF > frequency > setting, but this did no good. I'd sure like to see a detailed block > diagram, but > do not know where to look. > > I also tried turning on the "spur eliminator", which did help by several > dB, but > my birdie still sits a few dB able the displayed noise floor in the > narrowest > available resolution BW of ~ 3 kHz. > > So, for the moment, I'm out of ideas. > > Thanks, > > Dana > > > On Sun, Jan 17, 2021 at 5:21 PM Dan Kemppainen > wrote: > > > Dana, > > > > Just an FYI. Apparently, there are knockoff clone copies of the TinySA > > out there. (Yes, making a knockoff clone of a $50 spectrum analyzer is a > > thing, go figure!) > > > > Apparently, these have substandard performance, and a host of > > issues/concerns. I ran into this on the TinySA web site. They have some > > hints on how to detect if you have a clone or not. Might be worth > > looking into to see if you have a sub-par copy. > > > > Dan > > > > > > > > > > On 1/16/2021 12:00 PM, time-nuts-requ...@lists.febo.com wrote: > > > Date: Sat, 16 Jan 2021 05:45:19 -0600 > > > From: Dana Whitlow > > > To: Discussion of precise time and frequency measurement > > > > > > Subject: Re: [time-nuts] Leakage, tinySA > > > Message-ID: > > >> qrjlg-bw68wgdahmlhe9qulpupijuqedapz...@mail.gmail.com> > > > Content-Type: text/plain; charset="UTF-8" > > > > > > Another data point: My newly-received TinySA has a big birdie at 10 > MHz, > > > which is a > > > disappointment since I had hoped to use the unit as a sniffer to track > > down > > > leaks in my > > > 10 MHz distribution system. This birdie in the TinySA persists even > when > > > nothing is > > > connected to the input and does not vary in amplitude when I move > around > > > the house, > > > or with time while I'm sitting still with the unit. > > > > > > I, too, received no manual. > > > > > > Dana > > > > ___ > > 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.
Re: [time-nuts] Happy 20th Year
I concur! Thanks Tom. You guys have really helped me a lot along with all the archives and everyone on TN! Here's to an even better 2021. Maybe more better gear will show up on used market this year! I look forward to all the posts here! It seems a special kind of people appreciates time for what it is. Thanks. Bill On Fri, Jan 1, 2021, 6:33 PM wrote: > Thanks for the work in keeping this valuable resource up and running! > > Much appreciated. > > Corby Dawson > > > ___ > 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.
Re: [time-nuts] Rebroadcasting time signals [WAS: La Crosse Clocks - ]
@dana I bought one of the TinySA from the usa distributer. It even comes with an sma antenna that screws right on. I'm actually pretty amazed with how this little thing works! You can see the radio stations around easily along with other things if they're leaking. Really amazing little piece of kit. http://www.randl.com/shop/catalog/product_info.php?products_id=75243 This is the USA distributer with best price. Everyone else in the USA is just reselling at higher price from what I could find. Bill On Sun, Dec 27, 2020, 8:13 AM Dana Whitlow wrote: > It just occurred to me that one of the TinySA's could be handy for tracking > down > leaks like this. > > Dana > > > On Sun, Dec 27, 2020 at 8:02 AM Bob kb8tq wrote: > > > Hi > > > > If you can hear it on your radio with your normal antenna …. it’s > leaking. > > > > If you want to track it down, normal radio frequency direction finding > > techniques > > work. At 10 MHz a loop or rod antenna is likely your best bet. > > > > Bob > > > > > On Dec 27, 2020, at 5:05 AM, Hal Murray > wrote: > > > > > > > > > csteinm...@yandex.com said: > > >> (I know whereof I speak -- I spent quite a lot of effort a few years > > ago > > >> chasing down a leaking 10MHz reference of very dubious quality in use > > by a > > >> local ham nearly a kilometer from me.) > > > > > > Could you say more? What was the nature of the leak? How did you > track > > it > > > down? > > > > > > Is there a simple way that those of us who aren't radio-nuts can > measure > > how > > > much our GPSDOs are leaking? > > > > > > There is also "leakage" from switching power supplies. > > > > > > > > > > > > -- > > > These are my opinions. I hate spam. > > > > > > > > > > > > > > > ___ > > > 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.
Re: [time-nuts] Ublox 8T
I ordered some too for reduced offer price. BTW the seller is a she not a he in case you're interested. QUEEN*S_LAND is definitely a girl. I've seen her picture before. I'm interested in what you all come up with using these. I've bought a lot of stuff from her and she ships quickly. Bill On Wed, Dec 23, 2020, 8:18 PM Lloyd Blythen wrote: > Quick vote of confidence in case anyone's still considering buying any of > these (and in case there are any left - I haven't checked): I ordered two > on December 8th; they shipped with a tracking number on the 9th; and they > arrived in excellent condition on the 24th. Won't have a chance to play > with them for ages but they'll be useful. Thanks Bert! > > On Tue, 8 Dec 2020 at 03:14, ew via time-nuts > wrote: > > > With not much happening on Ublox 9T I went back looking at 8T in support > > for Jim Harnan's next generation GPSDO.. Shopping on ebay I ran across > this > > super deal. No financial interest but we have bought from him repeatedly > no > > problem. There is a reason he has 100%.. We have offered $ 15 for three > > each all accepted. Bert > Kehren > > > > > > > https://www.ebay.com/itm/ON-SALE-1-U-BLOX-ublox-LEA-M8T-0-10-HUAWEI-GPS-Module/333753811808?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649 > > > > ___ > > 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.
Re: [time-nuts] Ublox 8T
That's a really old board though. An 8 series isn't pin compatible with say LEA-6T is it? The picture had a 5 series in it. Could you use something like this? https://github.com/PaulZC/NEO-M8T_GNSS_FeatherWing/blob/master/LEARN.md Bill On Tue, Dec 8, 2020, 10:30 AM Gregory Beat via time-nuts < time-nuts@lists.febo.com> wrote: > There are various Breakout (bare) Boards for the uBlox modules posted on > Internet. > SparkFun has carried them, in the past, and sometimes sold the bare boards > without the uBlox module. > https://www.sparkfun.com/products/15005 > > StuartsProjects (Stuart Robinson, Cardiff, UK) has a bare board for the > Ublox MAX M8Q module. Sold on Tindie, used in high-altitude balloon > projects. > > https://www.tindie.com/products/stuartsprojects/ublox-max-8mq-gps-breakout-board-x-2/ > > Contact Limor “Ladyada” Fried at Adafruit, she might have bare boards OR > Gerbers for earlier or future products. > https://www.adafruit.com/?q=gps+breakout=1=BestMatch > > Dan Watson designed one, for the 6-series five years ago. > He sometimes posted Gerber files. > > http://syncchannel.blogspot.com/2015/09/a-nearly-perfect-u-blox-gps-breakout.html > > greg > w9gb > == > Date: Mon, 7 Dec 2020 09:47:55 -0500 > From: paul swed > To: Discussion of precise time and frequency >measurement > Subject: Re: [time-nuts] Ublox 8T > > Bert Very attractive price. They appear to be on a cut out circuit board. > How are you connecting to them please? > Regards > Paul. > WB8TSL > ___ > 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.
Re: [time-nuts] Manual: VARIAN R-20 Rubidium frequency standard.
The scans look good on the website. Thanks for the lead Tom. I still like collecting the original manuals for devices I have. You're right sometimes harder to find than the gear is! Bill On Sun, Dec 6, 2020, 6:10 AM Tom Van Baak wrote: > Nice find. Original manuals are sometimes harder to find than original > equipment. In the case of the Varian R20 there is a clean copy on fellow > time-nut Didier's website: > > http://www.ko4bb.com/manuals > > Search for Varian or R20. The 128 page file is: > > Varian_R20_Rubidium_Frequency_Standard_Service_Manual_1966.pdf > > See how your hardcopy compares with that PDF. FYI, there is a nice > history of Rb standards here: > > "A History of the Rubidium Frequency Standard" > > http://www.wriley.com/A%20History%20of%20the%20Rubidium%20Frequency%20Standard.pdf > > /tvb > > > On 12/6/2020 3:24 AM, Ulf Kylenfall via time-nuts wrote: > > Gentlemen. > > I have salvaged a manual for a Varian R-20 Rubidium Frequency Standard. > > > > It was left when my employer borrowed such a unit when > > performing the first cross-atlantic VLBI Experiments > > some time in the late 70's. The unit must have been returned to its > > owner but they forgot to include the manual... > > > > It is in excellent shape. > > > > Are there any such units still in operation? > > Is there a need for it? The thickness of the papers > > is about 1 inch. Most pages are easy enough to scan but the > > last 1/3rd is fold-out schematics for which I have no > > appropriate way to scan. > > > > Best Regards > > > > Ulf Kylenfall > > SM6GXV > > ___ > > 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.
Re: [time-nuts] Manual: VARIAN R-20 Rubidium frequency standard.
Ulf- I have the R-20 unit and no manual. I'd be very interested in it or scans of it please! Best Regards, Bill On Sun, Dec 6, 2020, 5:59 AM Ulf Kylenfall via time-nuts < time-nuts@lists.febo.com> wrote: > > Gentlemen. > I have salvaged a manual for a Varian R-20 Rubidium Frequency Standard. > > It was left when my employer borrowed such a unit when > performing the first cross-atlantic VLBI Experiments > some time in the late 70's. The unit must have been returned to its > owner but they forgot to include the manual... > > It is in excellent shape. > > Are there any such units still in operation? > Is there a need for it? The thickness of the papers > is about 1 inch. Most pages are easy enough to scan but the > last 1/3rd is fold-out schematics for which I have no > appropriate way to scan. > > Best Regards > > Ulf Kylenfall > SM6GXV > ___ > 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] Symmetricom 1050A
Does anyone have any manuals for the later model version of these? I don't think they've changed too much since FTS and Datum but I acquired 3 of the symmetricom units with disciplining option without any manuals. I'll take some pictures of the inside. I'm bringing them over to my lab today. Bill ___ 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.
Re: [time-nuts] Efratom M100 Found on Ramco auction site.
Good afternoon Dave- I've got a couple of these and the non military version FRK-L. They're good units with big Rb cells in them. They last a long time. Also you can actually work on them. Surface mount components inside. It's worth more than 5 pounds that's for sure. From what I've read the cell was capable of being replaced while the unit was running although I'd probably not try that! Bill aka notfaded1 On Mon, Nov 2, 2020, 2:49 PM Dave B via time-nuts wrote: > > https://www.bidspotter.co.uk/en-gb/auction-catalogues/ramco/catalogue-id-ramco-10255/lot-e55bd54e-6a87-44c7-8286-ac610134f040 > > Listed as a Crystal oscillator, but has a telltale mention of "Rb lamp > voltage signal" ! > > It's an Efratom Model M100 Listed for £5.00 UKP ! (Located in the UK.) > > (There are also some MI/IFR 2025 signal generators listed, and other RF > stuff.) > > No affiliation. > > Dave G8KBV. > > > > -- > Created on and sent from a Unix like PC running and using free and open > source software: > > > ___ > 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.
Re: [time-nuts] phase noise webinar from IEEE MTT-S
I attended too. This guy is so theoretical it was kinda hard to put into practical terms but I will say after reading some of his book he does understand some novel ways to calculate what's needed for reaching lower noise levels. Bill On Tue, Oct 13, 2020, 1:51 PM Attila Kinali wrote: > On Tue, 13 Oct 2020 12:46:46 -0500 > "Bill Byrom" wrote: > > > I just attended this webinar. It focused on oscillator design > > theory and the results the author had achieved for various > > specific projects. He discussed in general amplitude limiting to > > reduce amplitude noise, with the result that we only need to worry > > about phase noise in most cases. Very little time was spent on > > atomic clocks - he gave three slides which showed Rubidium > > resonance lines and vapor cells and a block diagram but there was > > little else. He discussed flicker noise but didn't get into the > > physical cause of that phenomenon. He spend a bit of time > > discussing frequency tweaking using varactor phase shifters. > > A couple of notes here: > > Everard is a great practical guy. He knows oscillators and he > knows them well. The papers comming out his group are great > resources on how to build oscillators for various applications. > I haven't had time to read his book yet, but the few pages I > looked at gave a very good impression. If you ever meet him > and have questions, he is very enthusiastic in answering them. > > About flicker noise: over a century after we discovered them, > we still do not understand how it comes to be. A bit simplified, > all we know is that defects increase flicker noise. But beyond > that, we have no idea how defects causes flicker noise. So I > am not surprised he doesn't go into that. > > Similarly, Rb vapor cells are not his business, oscillators and > filters are. He probably had just a project that was used in > an Rb standard, so it's understandable he didn't go into those > details either. > > Overall the presentation was a nice overview of his works. > > Attila Kinali > > -- > The bad part of Zurich is where the degenerates > throw DARK chocolate at you. > > ___ > 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.
Re: [time-nuts] Spectracom 8161 "Standard Frequency Receiver - Oscillator" for WWVB (and question...)
Is this why so many really high end devices are basically dumped on eBay now? I wondered why SRS device was so cheap now considering price of the SR620. It's too bad they don't work anymore. I'm sure when this happened it was a HUGE let down to many here that were using them? What's the best modern one of these for metrology use? Or has GNSS basically ended it? I'm very interested in your knowledge about these because I've really wondered how a modern one would compare to GNSS? Thanks, Bill .ılılı..ılılı. notfaded1 On Sun, Oct 4, 2020, 2:54 PM paul swed wrote: > Agree with Bobs comment. The 180 degree phase flip killed all of the gear > unless significant mods are done or the d-psk-r is used. Great old boxes > though. > Regards > Paul > WB8TSL > > On Sun, Oct 4, 2020 at 3:15 PM Bob kb8tq wrote: > > > Hi > > > > This is another of the many devices out there that pre-date the > > “modern” 180 degree phase modulation approach on WWVB. Getting > > one of these to run properly with the new modulation approach would take > > some major mods ….. > > > > Bob > > > > > On Oct 4, 2020, at 10:23 AM, Magnus Danielson > > wrote: > > > > > > Hi, > > > > > > I got a bit curious, so I dug up the manual (Available from Orolia that > > > Spectracom is part of): > > > > > > > > > https://www.orolia.com/sites/default/files/document-files/8161_manual.pdf > > > > > > It is apparent that the reference oscillator is actually free-running > > > but compared to the WWVB, so you manually tune it to make the > > > strip-chart become more of a flat line. > > > > > > This is interesting, because the receiver locks up another 10 MHz > > > oscillator. > > > > > > Now, there is a 45 degree (2.1 micro) modulation on the WWVB signal, > > > that shows up as time-tags on the strip-chart, so it is not trivially > so > > > that you just replace the simpler 10 MHz oscillator with the more > > > advanced, unless you can live with that modulation at which time it is > a > > > fairlly trivial hack. You can be a bit more cunning to add hardware to > > > compensate the modulation, but I wonder if that is what is done. > > > > > > To figure it out, one has to pop the lid to figure out. That is however > > > not for me to do. > > > > > > Anyway, I thought the manual pointer and quick analysis would maybe be > > > appreciated. > > > > > > Good luck! > > > > > > Cheers, > > > Magnus > > > > > > On 2020-10-04 09:37, Kirk Bailey wrote: > > >> I ran across an interesting widget in my ongoing "find the bottom of > the > > >> pile" task. Has a label indicating it was modified for "WWVB > Continuous > > >> Monitored". I thought these were all for WWVB, so what does > "Continuous > > >> Monitored" mean? See attached pic. If anyone is interested in being > > the > > >> new owner please contact me directly. > > >> > > >> Thanks, > > >> > > >> Kirk Bailey > > >> bai...@peak.org > > >> > > >> ___ > > >> 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. > ___ 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.
Re: [time-nuts] GPS Distribution amp selection?
Good morning Kevin- I use the same HP/Symmetricom units. Another newer brand, which carries GNSS frequencies, is from GPS Source: https://www.gpssource.com/collections/gps-splitter I have even seen some for sale on eBay for better prices used and bought some myself. Full disclosure I work for GD but I will say GPS Source makes some great modern GPS hardware. I've seen where they make these in Colorado Springs and they're legit newer hardware. Gogo Block III USA GPS! Regards, Bill On Mon, Sep 28, 2020, 1:56 AM Kevin Rowett wrote: > I’m in need of a GPS distribution amp. Looking at choices and what you’d > recommend. > > I have a GPS Networking 8 port in service, at one location. Has worked > without any issues. > > I need to add a distribution amp at another lab. > Amps I’m considering: > GPS Networkikng > 58516A > 58536A > > Other choices? > > I don’t need GNSS, just the USA GPS L1 frequency. I do need four ports. I > don’t mind used for this lab. > > I have read thru the archives, and TVB’s website - nothing stood out. > > Thank. > > KR, K6TD > > > ___ > 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.
Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.
Where I work on a smaller isolated network we have an APC that takes up one full rack. Most of the rack is modular batteries that are 6 batteries in 19" x 4U high... A bunch of rows of these in one rack with a few units that are the control and monitoring system. That one rack can support 6 rows of racks of equipment 5 19" racks wide. That one APC rack can run all the computers, NAS, blade centers, etc. for about an hour. Some of the racks are 110AC some are 208AC depending on circuit it's on. It seems like I could get one of the bottom of the rack APC units (really heavy) that are I think 4U high. The batteries usually last longer depending on the load. Our big unit tells you right on the front how long in minutes it will last based on the current load. Are you saying if the load is small it'll still run out pretty quickly? I was thinking just plug a few things in: BVA power supply, HP 105B, some GPS/GNSSDO's and the HP5065A. I don't even think there's any reason to plug a Cesium into it. If a Cesium in storage mode is off for a while who cares right? I have a few older Efratom Rb too FRK-L and a couple M-100. Would those benefit from staying on? I have a few newer Rb but they would just run until Rubidium ran out right like SRS PRS-10 and L-Pro's? I've heard the older Rb can be ran all the time because they have much more Rubidium in them. Up to this point I usually run them for a couple days to stabilize them before using them. I'm not 100% sure if leaving them on all the time is of much benefit? I know Ed told me he leaves his 5065 on all the time so I'm planning the same thing right now also mines recently put back together and as it runs it's getting better and better right now. I really like these older Rb units with larger physics packages. Best Regards, Bill On Sat, Sep 26, 2020, 9:16 AM Mark Spencer wrote: > A few decades ago I worked with some quite large Telecom gear that ran > from 208 volt AC.The equipment had its own internal 48 volt supplies > and short term battery back up system (basically so the redundant CPU units > could gracefully shut down in the event of a power failure.) The > manufacturer also sold similar systems that ran from customer supplied 48 > volts but many enterprise customers who already had large UPS systems and > back up generators preferred the versions that ran from 208 volt AC. > > Some smaller office phone systems back in the early 1990's also featured > large external battery packs to get multi hour run times. The vendors > would typically send technicians out to peridoically check the battery > systems. The few that I was able to examine were typically made up from 2 > volt sealed lead acid cells. The used cells used to be some what > available to hobbyists as the tended to get replaced before they failed. > > Yes some large UPS systems don't work very well at supplying low levels of > power for long the periods. During a multi hour maintenance shut down at > work a few decades ago we had one device that we hoped to keep running > (essentially a small digital voice play back unit that played phone system > messages, ie. "The number you have reached is not in service.") It drew > well under 100 watts and was the only load at the time for a large UPS > system with multiple battery banks which stopped running after a few hours > and I had to re record the messages. None of us were very surprised. > > > Mark Spencer > m...@alignedsolutions.com > 604 762 4099 > > > On Sep 26, 2020, at 12:33 AM, Hal Murray > wrote: > > > > > >>> Can't I just use a high quality APC backup power system > >>> like we use to power racks of gear in our Telco and compute closets? > > > >> Very few UPS's are good at long-run applications, they are typically > built to > >> run a heavy load for minutes, not a tiny load for hours or even days on > end. > > > > That matches my expectations, but somebody might expect their telco gear > to > > stay up longer than the few minutes it takes to cleanly shut down a > computer. > > > > Is there a branch of UPS gear aimed at telco rather than computers? > That is > > good efficiency at low power and long time rather than high power for > short > > time. > > > > Does all telco gear that is expected to run off UPS take 48V? > > > > Is there a market in small 48V supplies with UPS option for the telco > market? > > You would have to build a 48V to 24V converter rather than the whole > thing. > > You can probably get a brick for that. > > > > > > > > -- > > These are my opinions. I hate spam. > > > > > > > > > > ___ > > 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 >
Re: [time-nuts] What do people use for measuring temperature?
>From I know from measuring voltage references getting linearity in those kinds of temp ranges not only requires really good sensors but often it needs to be thermally bonded to what's being measured and often with some block of material that's makes swings in temperature much more subtle. Even a breeze in the lab or changes in the AC or heat from area causes big swings. Everything needs to be contained. Measuring temp that way when doing sub ppm voltage measurements isn't trivial. I'd be interested too if someone has built a better mouse trap for this? I keep my HP3458A right on top of my older 3456A. The 3456A is still an amazing piece of gear and GPIB is the way to go with it. I bought a Conductus LTC-21 temperature controller for doing temperature tests... temperature resolution of the LTC-21 is 1 part in 51200. I'm planning on using PT1000 RTD with it. It's one of those projects on the shelf for now but I've been slowly collecting the special connectors for the back if it although you can just stick some wire in there. Bill On Fri, Sep 25, 2020, 8:29 PM Bob Albert via time-nuts < time-nuts@lists.febo.com> wrote: > It would appear that the HP 3456A in temperature mode would meet your > needs. The 5k thermistor is very cheap. The temperature resolution is > very small, as I recall perhaps 0.001 degree but not sure. You can log > manually or via GPIB. Don't think its accuracy is anywhere near its > resolution but it's great for relative readings. > Bob > On Friday, September 25, 2020, 07:46:35 PM PDT, Hal Murray < > hmur...@megapathdsl.net> wrote: > > > I've got a collection of 1-wire gizmos and USB thumb drives. They are > great > for many applications but I'm looking for something better/different. > > I'd like something that reads to 0.01 degree or 0.001 degree. I don't > need > accuracy. What I want is reasonable linearity so I can make pretty graphs. > > I'd like the actual probe to be small enough so I can poke it inside gear > like > a PC and attach it to a crystal. > > I'm looking for a USB or serial connection so I can log the data. > > Is there an obvious brand/whatever I should be looking at? thermistor? > thermocouple? ... > > I don't care about a display on the device. I don't want a logger, they > fill > up. I want to grab the data on the fly and do my own logging. (But I'm > happy > to use a logger if it will do what I want.) > > > -- > These are my opinions. I hate spam. > > > > > ___ > 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.
Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.
Good evening TGIF! You've all given me some great ideas. I'm a computer scientist so tell me what's wrong with this? Can't I just use a high quality APC backup power system like we use to power racks of gear in our Telco and compute closets? A good one runs the full AC load the rack runs on. I've had maybe one or two short power outages in the last year and half at this house. The worst was less than a couple hours. Wouldn't it be good to put the few linear power supplies I want to keep on connected to the UPS. If I lost the counters or the DMM or really even the computers it's not that big of a deal isn't it the oscillators and OCXO's and their power supplies that really need to stay on? If I reduce the must have to them isn't it really all I need? I can restart the monitoring and computers. Ok so maybe I might get a small gap in data but the key is keeping the power supplies that drive the oscillators and their ovens running right? Thanks, Bill ___ 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.
Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.
I plan to keep BVA powered. My question was how do you accomplish this and what do you do it with? I've been using PS like for example Fluke PM2811, Tekpower TP3005T, Dr. Meter HY3005F-3 (these are similar), Sorensen and some older HP. I've had good luck them all so far. I'm curious if someone's found some better way that's smaller and newer and still good? It looks like a big UPS is in my future. Luckily I rarely have power outages here even in the desert of the southwest in AZ where the temp and even humidity is mostly stable inside in the AC in summer and even heat in the winter. It's dry in both cases inside in my lab. Do you monitor the thermistor along with the frequency and external temperature/humidty? I've been using this for external: http://www.dogratian.com/products/index.php/menu-sensors/menu-usb-pa-type-a-bmp085 It seems to work pretty well to monitor temp and humidity with USB for the room plugged into my computer. What I'm starting to think about is how do this on much larger scale at the same time? I have a few counters 53131, 53132, CNT-90, and an SRS SR620 but how do you do long term measurements over long extended periods on multiple powered up oscillators? Is there a mass way to do this? I know the computer could handle this with GPIB but is there another better way to say monitor all these variables on say 5 to 10 DUT constantly easier? I have an HP3458A but I wouldn't want to keep it tied up too long. The counters I run a lot so that's not a problem really. What do you orchestrate the whole thing with? I have labview NXG but I'm not sure some hardware DAQ or something with some scripts might not be better for multiple DUT than messing with labview running all the time. How do you do it? How do you get stats on multiple oscillators for years? I suppose some oscillators deserve their own dedicated counter 24*7 and maybe even a raspberry pi to sample the GPIB. I do have a few USB to GPIB interfaces and Pi's are pretty cheap but I've only got a 2 and a 3 right now. But then is there a timelab for Linux? I suppose the first main key is to just keep all the OCXO and GPSDO's powered all the time first on a UPS? Thanks, Bill ___ 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.
Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.
What power supply do you recommend for the BVA. I'm kinda partial to high quality linear power supplies. I'm not so concerned about the size or the efficiency. I'm more concerned with clean power that's stable like the oscillators I'm trying to power. I'd be interested in what others think? I know you can often get by with a switching power supply for some things and many OCXO and GPSDO's have they're own power filtering and smoothing to some degree. Bill On Thu, Sep 24, 2020, 12:46 PM Magnus Danielson wrote: > Hi Tom, > > I second this, these oscillators you want to power up and just leave for > them to settle and then keep powered. > > Next time I power down mine is to integrate a new supply and back-up > batteries, which can be a recommended little exercise. Currently only > the H-maser is on battery backup. > > Cheers, > Magnus > > On 2020-09-24 01:25, Tom Van Baak wrote: > > James Robbins wrote: > > > > > Oscilloquartz BVA has been sold. > > > > To the time nut who ended up with this BVA -- do not worry if it looks > > like it is broken when you power it up. These oscillators take their > > time to warm up. Here is a test I did last year on a similar BVA > > oscillator: > > > > "Oscilloquartz 8600-series OCXO warm-up" > > http://leapsecond.com/pages/osa-warm/ > > > > /tvb > > > > > > ___ > > 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.
Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.
Thanks Tom- I really appreciate your comment. I've studied your website closely on this topic. I'm really in awe of the 860x models some of you have access to 8607, 8608 models some with options! I'd probably be considered a newer school timenut/voltnut but... I even collect Nixie tube frequency counters... Separate topic but wow I just love cold cathode display technology and mixed with frequency... well dekatron counters too. Props to Jim for making BVA available here before putting on the auction site! I have mad respect for that. I've found some of the best people here. Best Regards, Bill On Wed, Sep 23, 2020, 4:29 PM Tom Van Baak wrote: > James Robbins wrote: > > > Oscilloquartz BVA has been sold. > > To the time nut who ended up with this BVA -- do not worry if it looks > like it is broken when you power it up. These oscillators take their > time to warm up. Here is a test I did last year on a similar BVA > oscillator: > > "Oscilloquartz 8600-series OCXO warm-up" > http://leapsecond.com/pages/osa-warm/ > > /tvb > > > ___ > 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.
Re: [time-nuts] eLORAN will be on the air GRI 99600
Isn't there also CDMA? We used a EndRun Technologies system not long ago that used a small short antenna that could be located inside and didn't need a cable to the roof for a GPS antenna. This was handy for rooms that couldn't have anything penetrate the walls at all. It was a good reference and ntp server we used for years that only used time reference from CDMA satellites. Bill On Thu, Aug 6, 2020, 1:43 PM jimlux wrote: > On 8/6/20 9:17 AM, Taka Kamiya via time-nuts wrote: > > Someone in this thread mentioned "at least 2 satellite time and > frequency solutions" exists already. I only know of GPS (GNSS) > constellations. What's the other? > > Transit? > > I don't believe they are still operational, though. > > > I wonder if one might be able to pick up time/frequency from a > commercial TV broadcast transponder. The transponders on the satellite > are typically bent pipes (for C-band anyway), I would assume that the > uplinks may or may not have stability comparable to terrestrial broadcast. > > One problem is, of course, that the satellites aren't in a stable > location (at least on a "meters" scale) - but one could certainly do > "common view" kinds of time transfer. > > > > > > > > --- > > (Mr.) Taka Kamiya > > KB4EMF / ex JF2DKG > > > > > > On Thursday, August 6, 2020, 12:01:27 PM EDT, paul swed < > paulsw...@gmail.com> wrote: > > > > Magnus > > Its honestly by luck that I know anything. From the bits I have read > Europe > > seems far closer to eLORAN then we are. Perhaps 6 months ago the US > > performed a series of tests 2 eLoran solutions and something like 6 or > more > > satellite solutions. I know the old Iridium satellites were in the tests > > and some other LEO satellites. > > But thats about it. > > What we need is a cheap SDR LORAN C sniffer. Low power runs 24 X 7 and > > turns a LED on if the stations active. > > Oh well another project in the someday pile. > > Regards > > Paul > > WB8TSL > > > > On Thu, Aug 6, 2020 at 2:42 AM Magnus Danielson > wrote: > > > >> Hi Paul, > >> > >> I only ask as you seem to track this thing the best here on time-nuts, > >> as far as I have seen, such that it is your emails that keeps me best up > >> to date with the progress. > >> > >> Cheers, > >> Magnus > >> > >> On 2020-08-05 19:21, paul swed wrote: > >>> Hi Magnus been a while since have emailed. > >>> Its one site that was a test transmitter. Its in New Jersey, USA. > >>> The goal of the testing I believe is to establish the viability of an > >>> alternate PNT reference to GPS. Additionally the ability to communicate > >>> some level of message broadcast. This should be identical to proposals > I > >>> have heard of in Europe. > >>> But I have no direct relationship to any of this. Like you, a very > >>> interested observer and hope that eLORAN wins the battle. > >>> Unfortunately there are many alternate proposals such as using other > >>> satellites. Hmmm if I wanted to advance my career in the Air Force or > >> Space > >>> Force (Yes thats actually real now). > >>> Would I select the lowly reliable as heck eLORAN at sub $100 M/year to > >>> operate. Or the glorious space based proposals in $B region. Never mind > >>> that at least 3 countries now have demonstrated killer satellites. > >>> Sorry for that editorial. > >>> Regards > >>> Paul > >>> WB8TSL > >>> > >>> On Wed, Aug 5, 2020 at 11:04 AM Magnus Danielson > >> wrote: > >>> > Hi, > > Do you know that they would do test with two actual transmitter sites? > > Cheers, > Magnus > > On 2020-08-05 16:00, paul swed wrote: > > Hello to fellow time nuts. > > Warm up those old Austrons. eLORAN out of New Jersey has been on the > >> air > > intermittently prior to a test run next week. Due to the storm they > >> have > > lost power and should have it back today or tomorrow. > > The intention will be on the air operation till the 20th. That's a > long > > run. Nice. > > Seems the Austron 2100s can be had for reasonable money these days > >> also. > > Enjoy. > > Paul > > WB8TSL > > ___ > > 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 --
Re: [time-nuts] Raspberry Pi NTP server
USB 1.0/Low-Speed: 1.5 Mbps USB 1.1/Full-Speed: 12 Mbps. USB 2.0/Hi-Speed: 480 Mbps. USB 3.0/SuperSpeed: 5 Gbps. USB 3.1/SuperSpeed: 10 Gbps. This is the actual bitrate for these serial interfaces. Bill On Wed, Jul 8, 2020, 5:16 PM jimlux wrote: > On 7/8/20 4:40 PM, Hal Murray wrote: > > > > stevesommars...@gmail.com said: > >> My RPi4 (Raspbian Buster) has a GPS+PPS/USB. Serial->USB uses Prolific > >> PL2303, which supports USB 2.0 > > > >> which means 1 msec polling of the PPS signal. I've been unable to > poll more > >> frequently > > > > As far as I know, the PL2303, 067b:2303, is an old/slow chip. (I forget > the > > right magic USB terms) Why do you expect it to go faster than 1 ms? > > > The underlying frame rate on USB (even the slowest USB1.0) is 8kHz, so > it's not unreasonable to expect that a chip might be able to "poll" a > status signal at that rate. > > > > > > It and the FTDI chip(s) are popular and widely known to be well > supported on > > Linux. I'll be very surprised if it goes faster. > > There is that. OTOH, drivers do get updated. One could probably, if you > were hard core, look at the device driver code in the Linux distro and > figure it out. > > > > > > What sort of device are you using? One way to tell if it is likely to go > > faster than 1 ms is the thickness of the wire. Faster speeds need more > > shielding for EMI reduction (or something like that) which turns into > fatter > > cables. It's pretty easy to tell if you have samples of both in front > of you. > > I think you can only use the thinner cable if t runs at 1 ms and you > hard > > wire the chip to the end of the cable as is typical of a GPS mouse. > > > > > > > > > ___ > 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] 5071A
If the power is cycled on one of these will it always go into attention mode yellow until cleared? Or will it go green continuous operation all in it's own? If one of these has been on the shelf a while is it common for one even with a good tube to report attention yellow for a while until tube pumps down and eventually will the yellow clear on it's own? Bill ___ 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] Turn Dynamic Systems FSA3011A timelab setup
Does anyone have any good docs or configuration experience with setting up timelab for FSA3011A? I'm curious what the best settings to start with are? I'm used to using SRS SR620, Pendulum, and HP 5313xA counters so far with timelab. The DTMD are new to me. I've got a bunch of Rb, OCXO, and GPSDO I want to compare and qualify. Bill in sunny Scottsdale, AZ. ___ 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.
Re: [time-nuts] Teensy 4.1
It's pretty legit and can run like any other Arduino does. With 100Mbit physical Ethernet built in that's pretty big for a tiny board. It supports the precision time protocol (PTP). Also known as IEEE 1588, this protocol allows for synchronizing connected devices with sub-microsecond precision. The size, price and features with that physical Ethernet is BIG! It has built in micro SD slot now too with more GPIO as well! Hot dang! Real-time microcontroller with a high-throughput data pipe = pretty bad @ss. $26.85 not bad at all 4 what you get! Bill On Thu, May 14, 2020, 3:15 PM Adrian Godwin wrote: > I just saw an update to the Teensy microcontroller line. > Teensys are somewhat like an arduino but generally with faster processors > and more memory. > > The latest one, 4.1, has an ethernet interface with IEEE1588 > packet timestamping. > > https://www.pjrc.com/category/news/ > > I'm not on pjrc's staff etc, but I like his products and as far as I know > this is a 'first' for such an interface on a cheap, fast development board > ($26, 600MHz). > ___ > 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.
Re: [time-nuts] OCXO Support Board
I've been trying to find a base PCB design to use too. In the interim I bought some boards from Gerry Sweeney that sells them for HP5313x frequency counter OCXO upgrades and supports different footprints. Open source design is even better. OSHpark is great. Please post it! Bill E. On Tue, May 12, 2020, 11:59 PM Matthias Welwarsky wrote: > On Dienstag, 12. Mai 2020 20:53:25 CEST Gerhard Hoffmann wrote: > > > Ten boards did cost $5 at PCBway, DHL wanted $25 for transport. :-< > > I can publish the Altium Designer project or the Gerber files when the > > 1st ten are used up > > and there has been somewhat more testing. The number of possible > > combinations > > is quite large. > > If you publish the Gerber files, People in the US can use OSHPark for > having > the boards made, in EU Aisler.net is probably the best option. > > BR, > Matthias > > > > > Cheers, Gerhard > > > > Am 12.05.20 um 19:52 schrieb Wes: > > > Does anyone know of a ready made board that will allow me to mount and > > > at the least, minimally support the operation of an MV89A oscillator. > > > I have one which I've powered up deadbug style and would like to clean > > > up the mess a little. > > > > > > Thanks > > > > > > Wes N7WS > > > > > > > > > ___ > > > 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] DATUM ExacTime 6010 info anyone?
I bought a DATUM ExacTime 6010 today that looks to have fully loaded option board on it. It'll be interesting to see what built in LO it has. It looks to have GPIB. I know some of these have firmware issues that were updated by symmetricom for leap second issues which required replacing an eeprom chip. I'm curious if anyone has ever tried replacing the GPS module in a device like this or copying a new newer eeprom chip to update with newer firmware? A friend of mine replaced SIRF in a spectratime GPSource Rb rack mount unit and replaced the it with a ublox LEA-M8T. I wonder if something like this could be done here? I know that both x72 and LPRO-101 were options on the ExacTime 6010. I'm hoping even if it doesn't have one of these options that adding one might not be too difficult. The unit has two jumpers inside to select the LO option whether TCXO, OCXO, X72, or LPRO. I've found the user manual for it. From what I know these have a lot of input and output options for the built in many BNCs it carries. It would really be neat to modernize this old piece of kit with better GPS and PPS. Here's some of the pics I saw before buying it. Bill ___ 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.
Re: [time-nuts] GPSDO advice on BG7TBL DO
Wes- A great resource for info is the BG7TBL master thread at eevblog. We track everything we know about these units to compare them: https://www.eevblog.com/forum/testgear/bg7tbl-gpsdo-master-reference/ Bill On Sun, May 3, 2020, 6:14 AM Wes wrote: > The seller and the PO did a yeoman job and the device arrived at 1 PM this > afternoon. > > It turns out to be a date code 2019-08-03 instead of the pictured 2018 > unit. A > pleasant surprise, but not the latest which is (I think) 2019-10-20. > > This one still says, "GPS Disciplined Oscillator", the newer one says, > "GNSS > Disciplined Oscillator." > > The OCXO is a CTS, labeled "970-2178-46". The receiver is unlabeled. > > I powered it up and it indicated lock in about 10 minutes using the > supplied > puck antenna on the workbench inside the house (concrete exterior > walls.)For > comparison, the TAPR Kit M12+ Oncore receiver located a couple feet away > with a > similar antenna situation shows lock on only three satellites using LH) > That > said, the only way I have to evaluate it is with the BG7TBL FA-2 counter > with a > Bodnar reference that has been running for weeks. It's continued to drift > for > over two hours and now has approached 10 MHz but is still wandering around > 4-5 > mHz with respect to the Bodnar. Which is correct is anyone's guess. > > I guess the next project should be to get the external antenna mounted and > splitter installed so everything is using the same source. > > Wes > > > ___ > 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.
Re: [time-nuts] GPSDO advice
Did you get a newer one with late 2019 at least on the front BG7TBL panel? The one I got doesn't have the frequency offset bug and works really well. It locks on multiple birds really quickly. For the money it's hard to beat. I've been comparing it to my Thunderbolt E. It obviously doesn't provide the extra info you get with Trimble protocol (so no ocxo info in Lady Heather) but I'd say it locks onto a lot more and faster than my Trimble does even if I put it on GPS only constellation for fair playing field. I hate to say it but I'm not sure my Thunderbolt is really much better. You won't be sorry if it's a later BG7TBL GNSS model. I've been running mine on GPS and Galileo lately. Bill On Fri, May 1, 2020, 8:25 PM Wes wrote: > Hi Bob, > > According to the USPS tracking number I'll have a BG7TBL GPSDO on Monday > :-) > > I really wanted to "Buy American" but a 10 dB price difference is worth > taking > the risk. > > Wes > > On 5/1/2020 7:29 PM, Bob kb8tq wrote: > > Hi > > > > I would guess that the vast majority of folks on the list and an even > > larger percentage doing the FMT are buying their GPSDO’s on eBay. > > Which ones they buy and how well the work is very much a “that depends > > sort of thing”. > > > > The crop of devices at low(er) prices changes every 3 to 5 years. > Whatever > > is being torn apart right now will be contributing the low cost stuff. > If you bought > > 5 years ago your choices were very different. Go back 5 or 10 years past > that and > > the devices change again and then again. > > > > There’s no reason to believe that “things were better in the old days”. > Mostly just > > different. The issues have been worked out on stuff that hit eBay 20 > years ago. > > That’s just the way it works. How well they have been worked out …. that > depends > > on the device and how picky you are. > > > > This does not simply apply to GPSDO’s. A while back eBay was awash in > telecom > > Rb’s. Some bought so many they can’t keep track of all of them. Today a > $35 listing > > for an Rb is pretty unusual. That’s just supply and demand. Wait another > 5 or 10 > > years and we probably will be awash in cheap ones again. > > > > Right now “entry level” GPSDO’s are still below $100 delivered. That’s > not all that > > crazy compared to a lot of gear in a typical shack or on a typical bench. > > > > Bob > > > >> On May 1, 2020, at 9:25 PM, Wes wrote: > >> > >> An update on this: > >> > >> I emailed both Jackson and Brandywine for prices on both the Desktop > Fury, in Jackson's case, and the board versions from each of them. > >> > >> The good news is that they both were responsive. The bad news is they > are both out of my price range. Jackson by about 3 dB. Brandywine clearly > didn't want to sell me anything, as exemplified by a fee of $47 to use a > credit card. > >> > >> As much as I would like to be more nutty, I can't justify spending this > kind of money just to participate in ARRL FMTs where the only direction I > have to go is down. > >> > >> Wes N7WS > >> > >> On 4/24/2020 11:56 AM, Wes wrote: > >>> Taking some of the advice offered, I've emailed them for P I'll > let you know if I hear back. > >>> > >>> Wes > >>> > >>> On 4/24/2020 10:45 AM, Kevin Rowett wrote: > > On Apr 24, 2020, at 10:32 AM, Mark Spencer < > m...@alignedsolutions.com> wrote: > > > > Speaking both as an amateur radio operator and some one who modestly > pursues precision time and frequency as a hobby, I am extremely happy with > my Jackson Labs Fury > > GPSDO. > Speaking of Jackson Labs, has anyone heard from them, since the > lockdown commenced? > > KR > > > ___ > 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.
Re: [time-nuts] Interesting 1-60 MHz =/- 50 ppb Stratum-3 TCXO chip
Looking at the datasheet it doesn't look like you'd win any ADEV competitions with it but it's small and the DCTXCO version would be nice to use the I2C interface and it says frequency control resolution as low as 5 ppt. It has uses I can see. Bill On Fri, May 1, 2020, 5:50 PM Richard Solomon wrote: > Been there, did a search on the part number and came up empty. > > They did have a "Request Samples" button so I filled out the form. Let's > see what happens. > > 73, Dick, W1KSZ > > On Fri, May 1, 2020, 5:40 PM jimlux wrote: > > > On 5/1/20 5:00 PM, Richard Solomon wrote: > > > Where do you buy these ? Their web site was not too illuminating. > > > > > > > > > digikey and mouser carry a lot of SiTime parts, including eval boards. > > > > > > > Tnx, Dick, W1KSZ > > > > > > On Fri, May 1, 2020, 4:31 PM mp...@clanbaker.org > > > wrote: > > > > > >> Hello, time Nutters-- > > >> > > >> I have been phase locking the freq counters in my HP 6-GHz VNA, > > Tektronix > > >> spectrum analyzer and bench freq counter to the 10 MHz signal from > > >> a Trimble Thunderbolt via a 4-port distribution box and long coax > cables > > >> to each of the instruments. This works well but is a pain in the tush > > >> connecting to long coax cables when the bench test gear are moved > > around. > > >> > > >> A friend suggested looking into some MEMS TCXO's made by SiTime to > > >> do this with. SiTime offers a wide variety of Stratum-3 TCXO chips. > > One > > >> of them is the SiT5358 which is spec'd at 0.05 ppm from 1 to 60 MHz. > > >> > > >> https://www.sitime.com/products/super-tcxos/sit5358 > > >> > > >> I am wondering what any feedback thoughts might be on this from > > >> the Time-Nuts gang? An eval-PCB board for the SiT5358 chip is > > >> available. What say the Time-Nutters gang about this approach for > > >> incorporating a small SiT5358 eval-PCB board into my bench test > > >> gear for phase locking to? I am also wondering which of the > > >> SuperStratum3 TCXO chips might be the best choice for a project > > >> like this? > > >> > > >> Any feedback on this is most welcome! > > >> > > >> Mike Baker > > >> Gainesville/Micanopy, Florida > > >> * > > >> > > >> > > >> > > >> ___ > > >> 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. > ___ 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.
Re: [time-nuts] Vaperware Parts and pulse stretching circuits
My Metcal is an MX-PS5000 that has two connections for irons. You can use both at the same time. I just love it. It's the best technology revolution in soldering ever. It doesn't use traditional resistance to heat it uses high frequency energy to heat the tip to the exact temperature and it does it in seconds. It heats and cools every time you pick it up to use it. It's cool in the magnetic base holder and it heats up by the time you pick it up and get it to the board in seconds. It then cold down really fast almost the same way. The temperature is exactly the same every time. They use them where I work to solder for space applications in factories. I'm CIS engineer but I've learned what works from watching them. Here are the Amazon magnifying glasses I use for soldering. I use the highest level thickest lenses but you don't have to: https://www.amazon.com/Dicfeos-Headband-Magnifier-Mounted-Magnifying/dp/B075WR4M99/ref=sxin_9_ac_m_rm The price can be right on both the glasses are cheap and you can get used Metcal from eBay. That's where I got mine. Also new tips are also everywhere. Everytime a company shuts and sells their stuff it ends up out there and some is new almost. Bill On Sat, Apr 25, 2020, 6:07 PM Bryan _ wrote: > They make quite a few models which one are you recommending? > > -=Bryan=- > > > From: time-nuts on behalf of Bill > Notfaded > Sent: April 25, 2020 5:38 PM > To: Discussion of precise time and frequency measurement < > time-nuts@lists.febo.com> > Subject: Re: [time-nuts] Vaperware Parts and pulse stretching circuits > > I totally agree with the Metcal soldering station!!! I'll never go back to > anything else. I don't even use a scope. I bought some magnifying glasses > with 5 sets of different power lenses you wear like glasses. It has built > in led light and adjustable strap that hold it on your head off Amazon. > Works great. I can do all small surface mount stuff with them. Plus I > have my normal vision and hand eye coordination going that way. Soldering > under a scope or on a video monitor is a lesson all in itself! > > Bill > > On Sat, Apr 25, 2020, 6:15 AM Gerhard Hoffmann < > g...@hoffmann-hochfrequenz.de> > wrote: > > > > > Am 25.04.20 um 13:41 schrieb John Ackermann: > > > I do have a microscope (cheap Chinese unit, maybe $400 with articulated > > arm and the works) and it does make things much easier. But as long as > you > > can see the work, you can do the job. > > > > > > It's not that hard to do small pitch parts. I usually do the best I > can > > soldering individual pins, knowing their will be bridges, then clean up > > with solder wick and *lots* of no-clean flux. You can never have too > much > > flux. I've found a 1.6 mm chisel tip is a good all around size for SMD > > work, though I have a 0.8 mm chisel available for when things get tight. > > > > > > The hardest part is getting the first couple of pins tacked down so the > > part is square on the pads. After that it's fast. > > > > > > John > > > > I have about the same here, plus a cheap Chinese Ayoue852 hot air > > station. Exchanging the Weller for a Metcal was the biggest improvement > > after the LED ringlight for the microscope. > > > > In my quest to scrutinize the 1/f region, I have built some chopper > > amplifiers and the newest one will have GaN transistors that are nekkid > > chips with jut 4 tin bumps below. No case, just the passivated chip, 1 * > > 1 mm, EPC2038. Low channel resistance, even lower capacitance -> low > > charge injection. Resistors are 0603. > > > > Fearing I could not handle them, I made a minimum version of the switch > > itself as a test structure in an unoccupied corner of a different > > project. But soldering did take just 3 minutes, it was surprisingly > > easy. Just keep the air flow low enough, or you will have trouble to > > find the chips again. The thick-liquid flux helps to fix the chips in > > place. > > > > Legible part numbers on the board are hopeless at this scale. The board > > was made by PCBway, there were some discussions about having solder mask > > ON part of the pads, and some discussions with our German customs that > > you cannot buy 10 boards for $10 or so. > > > > The chips are the gray squares between the 2 vias on the left and the 4 > > huge coupling capacitors. > > > > Cheers, Gerhard > > > > > > ___ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time
Re: [time-nuts] Vaperware Parts and pulse stretching circuits
I totally agree with the Metcal soldering station!!! I'll never go back to anything else. I don't even use a scope. I bought some magnifying glasses with 5 sets of different power lenses you wear like glasses. It has built in led light and adjustable strap that hold it on your head off Amazon. Works great. I can do all small surface mount stuff with them. Plus I have my normal vision and hand eye coordination going that way. Soldering under a scope or on a video monitor is a lesson all in itself! Bill On Sat, Apr 25, 2020, 6:15 AM Gerhard Hoffmann wrote: > > Am 25.04.20 um 13:41 schrieb John Ackermann: > > I do have a microscope (cheap Chinese unit, maybe $400 with articulated > arm and the works) and it does make things much easier. But as long as you > can see the work, you can do the job. > > > > It's not that hard to do small pitch parts. I usually do the best I can > soldering individual pins, knowing their will be bridges, then clean up > with solder wick and *lots* of no-clean flux. You can never have too much > flux. I've found a 1.6 mm chisel tip is a good all around size for SMD > work, though I have a 0.8 mm chisel available for when things get tight. > > > > The hardest part is getting the first couple of pins tacked down so the > part is square on the pads. After that it's fast. > > > > John > > I have about the same here, plus a cheap Chinese Ayoue852 hot air > station. Exchanging the Weller for a Metcal was the biggest improvement > after the LED ringlight for the microscope. > > In my quest to scrutinize the 1/f region, I have built some chopper > amplifiers and the newest one will have GaN transistors that are nekkid > chips with jut 4 tin bumps below. No case, just the passivated chip, 1 * > 1 mm, EPC2038. Low channel resistance, even lower capacitance -> low > charge injection. Resistors are 0603. > > Fearing I could not handle them, I made a minimum version of the switch > itself as a test structure in an unoccupied corner of a different > project. But soldering did take just 3 minutes, it was surprisingly > easy. Just keep the air flow low enough, or you will have trouble to > find the chips again. The thick-liquid flux helps to fix the chips in > place. > > Legible part numbers on the board are hopeless at this scale. The board > was made by PCBway, there were some discussions about having solder mask > ON part of the pads, and some discussions with our German customs that > you cannot buy 10 boards for $10 or so. > > The chips are the gray squares between the 2 vias on the left and the 4 > huge coupling capacitors. > > Cheers, Gerhard > > > ___ > 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.
