Re: [time-nuts] Fluke Voltage Standards.

Had the HP equivalent for a while. Required special cords to bring the voltage to the DUT. Buyer Beware. Haven't seen a Fair Radio catalog in years, not since I sold the R-39x equipment. There's a big difference between the accuracy of a voltage standard and a time standard. Perhaps this is becaus

Re: [time-nuts] China Oscillator Alternative

These have 10Mhz & 15Mhz out, which frequency is the OCXO? Ed On 11/9/2016 7:18 PM, Perry Sandeen via time-nuts wrote: List, After all the problems that Bob Camp has noted with surplus OCXO's from China, perhaps buying the new Lucent units on Ebay may save bad words and/or unhappy actions.

Re: [time-nuts] Sapphire oscillators

there was another sapphire oscillator company: Industry News / Test and Measurement Channel A Mobile Ultra-low Phase Noise Sapphire Oscillator Intr

Re: [time-nuts] 5071A with ATTENTION flashing

Hi I have said goodbye to this one. There are 5 more 5071A with yellow led flashing to visit this weekend. Regards LiAng BI7LNQ ---Original--- From: "Tom Van Baak" Date: 2016/11/10 06:28:45 To: "Discussion of precise time and frequency measurement"; Subject: Re: [time-nuts] 5071A with ATTENT

Re: [time-nuts] China Oscillator Alternative

On Thu, 10 Nov 2016 00:18:31 + (UTC) Perry Sandeen via time-nuts wrote: > After all the problems that Bob Camp has noted with surplus OCXO's from > China, perhaps buying the new Lucent units on Ebay may save bad words and/or > unhappy actions. Depends on what you are after. IMHO, unless th

Re: [time-nuts] Sapphire oscillators

A lot of hype has been coming out of the left coast down under for many years, with this being the latest example. This technology tends to produce the world's most sensitive microphone. It's also a fairly sensitive thermometer, too, which the helium bath tends to mask. The prices asked have ten

Re: [time-nuts] Sapphire oscillators

On Thu, 10 Nov 2016 11:20:37 +1100 Jim Palfreyman wrote: > Anyone got any comments on this? > > http://www.theleadsouthaustralia.com.au/industries/technology/worlds-most-precise-clock-set-for-commercial-countdown/ Cryogenic sapphire or whispering gallery mode oscillators have been around for qu

[time-nuts] Top Posting

List, There is always going to be some top posting however it has been six or seven pages long multiple times lately. I save all these on MS word for reference later.  How about shortening these at least a little bit please? Regards, Perrier ___ time-nu

[time-nuts] Fluke Voltage Standards.

List, Fair Radio which has been in the surplus electronics business almost forever has two models of Fluke standards for sale. They have a sterling reputation. FLUKE-332A  $100 Voltage Standard - Used Reparable     FLUKE-332B  $125 Voltage Standard - Used Reparable IIRC, this means they will

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoCserial port for ntpd

Hi Bob, Yes! And that's all the more reason I encourage people that design hobby prototypes or commercial products to treat precise time with some dignity and respect. Embrace the challenge. There is no reason that the leading edge, pulse width and trailing edge, or the rise time, fall time and

[time-nuts] China Oscillator Alternative

List, After all the problems that Bob Camp has noted with surplus OCXO's from China, perhaps buying the new Lucent units on Ebay may save bad words and/or unhappy actions. LUCENT/SYMMETRICOMKS-24361 L101, Z3812A, RFTG-U REF-0 UNIT -CASE OF 2 EACH  $80 So for about $50 each delivered one has two

[time-nuts] Sapphire oscillators

Anyone got any comments on this? http://www.theleadsouthaustralia.com.au/industries/technology/worlds-most-precise-clock-set-for-commercial-countdown/ Jim Palfreyman ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.feb

Re: [time-nuts] Need some wisdom from the cesium beam tube gurus out there

Skip Not the expert but as you say the lower oven temp means higher em and visa versa. Funny you mention no writing in some document or ebay pixs I saw the same thing a tube with no details. So that now makes 2 instances of no marking. My non-professional 10 cents put a tube in you know. Set EM to

Re: [time-nuts] Need some wisdom from the cesium beam tube gurus out there

Hi I would bet that they started as you have with a low oven setting and cranked it up based on stability data. Once they got to that point, add a bit to have enough margin on the tube for it to last the rated life. Since there are multiple quantum “modes” the beam can get into, there may hav

[time-nuts] Need some wisdom from the cesium beam tube gurus out there

Hello Time-Nuts, I have been checking out some cesium beam tubes lately and have run into an interesting one. The tube is a standard HP 05061-6077 unit. There are two labels on these tubes, one at the end that has a serial number, and the other large label on the side that has the operating info

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

Hi Adrian, Then I apologize for doing such a poor job of getting my meaning across.  What I was trying to show was that for a number of reasons, you can't necessarily trust the trailing edge of a 1PPS pulse.  If you're generating a pulse every second from a clock, and that's all your doing, then

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

Hi > On Nov 9, 2016, at 6:28 PM, Bob Stewart wrote: > > Tom, > How many times have people posted here, on time-nuts, not to trust the > trailing edge of a 1PPS pulse? The rest of the caution is : The leading edge is the one that is “on time” and the second edge is an unknown offset from it

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

But trailing isn't the same as falling. The leading edge can be of either polarity. On Wed, Nov 9, 2016 at 11:28 PM, Bob Stewart wrote: > Tom, > How many times have people posted here, on time-nuts, not to trust the > trailing edge of a 1PPS pulse? > > Bob --

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

Tom, How many times have people posted here, on time-nuts, not to trust the trailing edge of a 1PPS pulse? Bob - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Tom Van Baak To: Discussion of pr

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

Bob, The PIC's I use have essentially no jitter. If they generate a 1PPS the edge and the pulse width are perfect, down to picoseconds. The talk about "other stuff" and "priority" and "number of compares" and "ambiguity" is worrisome. It sounds like a design or coding flaw to me, like what happ

Re: [time-nuts] 5071A with ATTENTION flashing

Hi Li, 1) When there is a "fatal error" the unit goes back into standby mode, where the Cs oven is turned off. Hence the Cs oven temperature error will again be at its maximum value (which is that -9.55 number). This is by design. I use a script to send a scpi syst:print? command once a minute,

Re: [time-nuts] 5071A with ATTENTION flashing

Regarding error codes in the 5071A. This "feature" was an afterthought. All of us hardware designers brought out test points that were easy to implement and then the microcontroller polled them and software was written to give error reports. We did what was easy on already finished board design

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

I'd like to comment on the idea of measuring the width of the pulse.  My experience with creating the 1PPS from an interrupt is that it's fairly straightforward how to do the set interrupt:  The interrupt happens, you execute one, maybe two instructions to raise the output pin, and you leave the

Re: [time-nuts] 5071A with ATTENTION flashing

Yes, I'm sorry about that. On Wed, Nov 9, 2016 at 5:18 PM, paul swed wrote: > Adrian > I think you may have responded to the wrong thread?? > Regards > Paul > > On Wed, Nov 9, 2016 at 10:21 AM, Adrian Godwin > wrote: > > > I'm still struggling to get the acrylic I need. I've been into London a

Re: [time-nuts] 5071A with ATTENTION flashing

Adrian I think you may have responded to the wrong thread?? Regards Paul On Wed, Nov 9, 2016 at 10:21 AM, Adrian Godwin wrote: > I'm still struggling to get the acrylic I need. I've been into London a few > times but not been able to get to the shop in business hours. Guess I could > order onlin

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

FWIW, the 16450 uart can interrupt on any modem line change, whether it be rising or falling. On Wed, Nov 9, 2016 at 11:41 AM, Chris Albertson wrote: > On Tue, Nov 8, 2016 at 11:08 PM, Hal Murray > wrote: > > > > > g...@rellim.com said: > > > Who cares if the PPS is inverted? > > > > If the sig

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

On Tue, Nov 8, 2016 at 11:08 PM, Hal Murray wrote: > > g...@rellim.com said: > > Who cares if the PPS is inverted? > If the signal is NOT inverted then the raising edge will be within nanoseconds of the UTC seconds "tick".The inverted PPS will have the edge delayed somewhat. It is not even

Re: [time-nuts] 5071A with ATTENTION flashing

I'm still struggling to get the acrylic I need. I've been into London a few times but not been able to get to the shop in business hours. Guess I could order online if necessary but it will cost a fair bit more. On Wed, Nov 9, 2016 at 3:19 PM, paul swed wrote: > I saw the low CBT temp also and 1

Re: [time-nuts] 5071A with ATTENTION flashing

I saw the low CBT temp also and 10 degrees C seem like allot. However in the 5060/5061 Frankenstein I run the oven at +10 degrees (approx.) to what the tube asks for. To drive C fumes out of the oven. A possible assumption is the cooler oven is emitting fewer C's and the emult is trying to make up

Re: [time-nuts] How to get PPS from ublox mini-PCI GPS to APU2 SoC serial port for ntpd

Just make sure you get a board with more than one Rx/Tx pair, unless you are happy with two boards; one for Rx/Tx and one for PPS. On Wed, Nov 9, 2016 at 2:08 AM, Hal Murray wrote: > > g...@rellim.com said: > > Who cares if the PPS is inverted? > > Good point. I wasn't paying attention to the P

Re: [time-nuts] 5071A with ATTENTION flashing

that's telling you that the CBT oven is not up to temp so you could have a failed heater in the tube or the oven controller is malfunctioning The former well you need a new tube which symmetricom will be happy to sell you for a 5 figure price tag. The latter is limited by your repair skills a

Re: [time-nuts] 5071A with ATTENTION flashing

According to the Log, "CBT Oven Err: -9.55 C" might be something wrong. However, I can't find the correct range in the manual. Does anyone have the information about this parameter? Regards Li Ang -- Original -- From: "Li Ang";<379...@qq.com>; Date: Wed, No