Re: [time-nuts] eLoran is up and operating. Looking good

. It’s just that nobody has ever bothered to do it. Coming up with some simple to use tools to estimate the errors and config them in is likely the only practical way to do it. Bob > On Feb 7, 2017, at 12:10 AM, Ruslan Nabioullin <rnabioul...@gmail.com> wrote: > > On 02/06/2017 09:

Re: [time-nuts] eLoran is up and operating. Looking good

Hi > On Feb 6, 2017, at 7:38 PM, Ruslan Nabioullin wrote: > > So any ideas on how likely it will be that eLORAN becomes deployed with at > least partial US coverage within the next 5--10 years? No, this is not the world as I would like it to be. It is the world we live

Re: [time-nuts] low power, but quiet, oscillators

Hi > On Feb 6, 2017, at 7:35 PM, Magnus Danielson <mag...@rubidium.dyndns.org> > wrote: > > Hi, > > On 02/07/2017 12:36 AM, jimlux wrote: >> On 2/6/17 2:37 PM, Bob Camp wrote: >>> Hi >>> >>> One of the most basic reasons for putting

Re: [time-nuts] low power, but quiet, oscillators

HI > On Feb 6, 2017, at 6:36 PM, jimlux <jim...@earthlink.net> wrote: > > On 2/6/17 2:37 PM, Bob Camp wrote: >> Hi >> >> One of the most basic reasons for putting out > +20 dbm is that you >> had a spec of -195 dbc / Hz for the noise floor :) >&

Re: [time-nuts] low power, but quiet, oscillators

Hi One of the most basic reasons for putting out > +20 dbm is that you had a spec of -195 dbc / Hz for the noise floor :) Some of these specs *are* a bit mutually exclusive. Bob > On Feb 6, 2017, at 3:19 PM, jimlux wrote: > > We're always looking for low DC power,

Re: [time-nuts] Lucent KS-24361 REF 0 standalone

Hi The only serial dialog between the two units is a repeat of the output of the GPS module. My guess is that there is some subtle difference between the Oncore data and they skytraq…. Bob > On Feb 6, 2017, at 1:23 PM, Thomas Petig wrote: > > Hi everyone, > I am currently

Re: [time-nuts] Optimal oscillator topology for diffrent frequency range

Hi One could easily spend years answering this sort of question. Several people on the list *have* done so. Two of them have already tossed up answers. What are you trying to do? What is your definition of “low”? How well equipped are you to test this sort of thing? How much tweaking are

Re: [time-nuts] What interrupts aging?

: is the quartz in a high quality quartz crystal perfect?That > is; is the > > crystalline lattice perfect, without flaws or impurities? I assume that the > quartz is > > grown in a furnace, can we grow perfect quartz crystals? > > Pete. > > > On 2/5/2017

Re: [time-nuts] What to do with a 5061A/5061B with dead NiCds

HI Unless you are in a *very* unusual location, put it on a UPS. Bob > On Feb 5, 2017, at 6:27 PM, Skip Withrow wrote: > > Hello time-nuts, > > I have 5061A and 5061B units with the battery option and dead battery > packs. My question is what makes the most sense

Re: [time-nuts] What interrupts aging?

Hi Aging can be caused by many things. Stress on the blank (and can and leads and plating and …) is one source. There are good reasons to believe that quartz vs metal stress can take > 1 month to settle out to the 90% level. Particle (think borders down to atoms) equilibrium inside the can is

Re: [time-nuts] information about the Austron Synchronous Filter 2090A

Hi Best guess - it was intended for use in close proximity to a Loran chain transmit site. The Austron Loran receivers only had about a 100 db dynamic range. If you needed to operate close to a transmitter … that’s not enough. Bob > On Feb 5, 2017, at 3:20 AM, Ruslan Nabioullin

Re: [time-nuts] Power Problems Lucent KS-24361, L101 & L102

Hi The power “brick” is a pretty standard Lucent part. The show up from time to time on the surplus market. The gotcha is that you may be able to buy a KS box for less than the asking price for the power brick. There are no schematics on these devices other than what some people have traced

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

Hi For NTP grade timing, there are still a lot of broadcast sources out there. You *do* need to be careful about propagation and when to (not) use them during the day. Focusing effort on that part of it is probably more useful than waiting for funding to appear for eLoran…. Bob > On Feb 4,

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

Hi The ground wave (hopefully) travels a shorter path. The gotcha comes in when the phase shift is 180 degrees and you start nulling things out. That will play havoc on the “stuff” that works out the envelope shape for detecting the third pulse. Again, I didn’t design a from scratch receiver

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

chain … no way to figure out which data was correct. Bob > On Feb 4, 2017, at 3:05 AM, Ruslan Nabioullin <rnabioul...@gmail.com> wrote: > > On 02/03/2017 09:53 AM, Bob Camp wrote: >> With reasonable gear, you can pick up the European Loran chains in >> the US on a regul

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

Hi The spectrum is about what you would expect from a bunch of short pulses. http://phk.freebsd.dk/loran-c/theoretical_spectrum/ Bob > On Feb 3, 2017, at 4:40 PM, Hal Murray wrote: > > > kb...@n1k.org said: >> the signal shows up over many 10’s of KHz of bandwidth

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

Hi Loran C is a pulse based system. All transmitters world wide run on the same 100 KHz frequency. The thing that distinguishes one transmission from another is the repetition rate of the signal. If you have a spectrum analyzer and hook up a piece of wire near one of the transmitters, the

Re: [time-nuts] distribution amp question + hp 59309A

Hi The gotcha with transformer coupled coax is keeping it terminated over a wide range of frequencies. If the coax is miss terminated and the end of the cable is floating, you have a pretty good opportunity for noise to get into the system. Floating shields are also a pretty good way to get

Re: [time-nuts] Distribution amplifier (again!) - now mostly ok but has gain peaking

Hi The real question is: Do you have an application where < 100 ps matching matters? If so do you need to match both at the amplifier *and* at the ends of the cables? Other than a phased array radar, I can’t think of to many situations where the answer is yes … Put another way, for the

Re: [time-nuts] How good is the left end of your ADEV curve?

> On Jan 25, 2017, at 12:15 AM, Hal Murray wrote: > > way way way left. > > Ray Weiss was the speaker at the Stanford Physics Colloquium today. In case > you don't recognize the name, he is one of the leaders of the LIGO project > that detected gravity waves about a

Re: [time-nuts] Autodesk Eagle -- maybe they're listening

Hi The big gotcha in moving between these programs is porting the libraries. Without moving them over, you have very limited options when working in the “new” environment. Opened up the email this evening and *surprise* a discount coupon from Autodesk. Charge a lot as a “standard”

Re: [time-nuts] Autodesk Eagle -- maybe they're listening

Hi > On Jan 23, 2017, at 8:28 PM, Jim Pruitt wrote: > > Mike, you are correct about Autodesk products being free to > students/faculty/and staff with proof of status. A college/university > email would do that. > > I retired from a medium size state university here in

Re: [time-nuts] Thermal effects on cables

gt; wrote: > > On 1/23/17 9:16 AM, Bob Camp wrote: >> Hi >> >> Nothing is ever simple if you dig deep enough: >> >> http://www.jensign.com/RG58U/ >> >> http://www.cliftonlaboratories.com/the_curious_case_of.htm >> > > here's my guess on t

Re: [time-nuts] Thermal effects on cables

Hi Nothing is ever simple if you dig deep enough: http://www.jensign.com/RG58U/ http://www.cliftonlaboratories.com/the_curious_case_of.htm Bob > On Jan 23, 2017, at 10:13 AM, REEVES Paul > wrote: > > Hi David, > > Surely the impedance of the cable is only

Re: [time-nuts] purpose of time of day display units

Hi Trying to troubleshoot those racks *without* being able to see the timing is harder than if you can. This gizmo should trigger at the top of the minute. Did it trigger? That’s much easier to catch if you can see the minute transition. If the rack goes down, it needs to be back up fast…..

Re: [time-nuts] 10MHz to 25MHz

Hi > On Jan 21, 2017, at 2:52 PM, Charles Steinmetz wrote: > > jimlux wrote: > >> I forgot to watch (actually, I knew it was today, but I thought >> it would be on this afternoon, not at 7AM).. >> >> (and, I'll get a call from management on Monday.. uh, Jim, about that

Re: [time-nuts] 10MHz to 25MHz

Hi So what we are all now scrambling to find a copy of is season 3, episode 62 originally aired 1/21/2017 of Innovation Nation. Bob > On Jan 21, 2017, at 2:09 PM, jimlux wrote: > > On 1/21/17 10:24 AM, steve heidmann via time-nuts wrote: >> WoW . I don't know if I'm

Re: [time-nuts] 10MHz to 25MHz

Hi > On Jan 21, 2017, at 10:25 AM, jimlux <jim...@earthlink.net> wrote: > > On 1/20/17 7:10 PM, Bob Camp wrote: >> Hi >> >> There are several other materials that you can make crystal resonators out >> of that >> are piezo electric. Some o

Re: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year

ired. Its really not going to change. When > a company is acquired what ever had been stated positions no longer matter. > Its not the same company any longer, just the same name. > So exploring alternates as you are all doing is great and helpful. > Regards > Paul > WB8TSL > &

Re: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year

Hi Fusion 360 has the same sort of “slurp it up” and “net connection” requirements. Anything you do is (at least potentially) not exclusively yours. Fine for a basement. As you point out a bit nuts for any corporation. My guess is that there is or will be some sort of corporate server

Re: [time-nuts] 10MHz to 25MHz

gt; KJ6UHN > Alex > > > > On 1/20/2017 8:38 AM, Bob Camp wrote: >> Hi >> >> If you think about it, current through the crystal is at least as important >> as >> “drive level”. They are related by the crystal resistance. As the overtone >> go

Re: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year

o offer the integrated solution where the PCB and > case that it lives in are designed together by a team that is > geographically distributed. > > On Fri, Jan 20, 2017 at 8:58 AM, Bob Camp <kb...@n1k.org> wrote: >> Hi >> >> I completely agree that their spin at acquisi

Re: [time-nuts] PN/AM and 1.5Hz spur from frequency doubling?

Hi I would bet that the spur moving is an indicator of either the 25 MHz transmitter carrier or modulator drifting in frequency. My guess is that the Maser does not drift :) Bob > On Jan 20, 2017, at 12:22 PM, Anders Wallin > wrote: > > I made some progress with

Re: [time-nuts] Thunderbolt Harmonics

Hi > On Jan 20, 2017, at 11:22 AM, Tom Miller wrote: > > > - Original Message - From: "jimlux" > To: > Sent: Friday, January 20, 2017 8:34 AM > Subject: Re: [time-nuts] Thunderbolt Harmonics > > >> On 1/19/17 8:48

Re: [time-nuts] 10MHz to 25MHz

level on > say the fifth overtone versus the fundamental? I would guess at 100 MHz it > may be 3rd or 5th, or are they fundamental? > > The comments one drivelevel are simply based on snr, larger signal with > same noise, better snr > > On Thu, Jan 19, 2017 at 7:06 PM Bob

Re: [time-nuts] OT: Eagle PC CAD now Autodesk, $500/year

Hi I completely agree that their spin at acquisition and the reality of what just came out is completely amazing. They said they would never do this and that. What they are doing is exactly what they said they would not do. It’s a rare board that I do in < 4 layers. It’s also quite normal to

Re: [time-nuts] Thunderbolt Harmonics

Hi > On Jan 19, 2017, at 11:48 PM, Rhys D wrote: > > Thanks for the detailed post Bill, > > I'm learning a lot here! > So the spectrum analyser is indeed a "trap for young players" > As you guessed, it is a Siglent SSA3000X series analyzer. > > I just looked at the same

Re: [time-nuts] 10MHz to 25MHz

Hi > On Jan 19, 2017, at 2:42 PM, Bryan _ wrote: > > Wouldn't designing circuitry and PCB's be easier with 10Mhz vs 100Mhz? Maybe > not so much now but then. Design in general might be a bit easier at the lower frequency “way back when”. I’ve never run into it as an

Re: [time-nuts] Detector Matching

Hi Not sure this is on topic for the group, but here’s the simple answer: Your diode detector does not present a constant load as the power goes from -50 dbm to 0 dbm. If you have a matching circuit, it can only work at one power level. In addition, you have frequency effects. The simple

Re: [time-nuts] 10MHz to 25MHz

> On Jan 19, 2017, at 3:03 PM, Scott Stobbe <scott.j.sto...@gmail.com> wrote: > > Wouldn't crystal drive level be one of the important specifications for far > out phase noise? > > On Thu, Jan 19, 2017 at 1:33 PM, Bob Camp <kb...@n1k.org> wrote: > >

Re: [time-nuts] 10MHz to 25MHz

n Thu, Jan 19, 2017 at 1:33 PM, Bob Camp <kb...@n1k.org> wrote: > >> HI >> >> A lot of your evaluation of the term “better” will depend on your intended >> use. One of the limits on phase noise >> is the thermal noise floor. Because of that, starting at

Re: [time-nuts] 10MHz to 25MHz

HI A lot of your evaluation of the term “better” will depend on your intended use. One of the limits on phase noise is the thermal noise floor. Because of that, starting at a higher frequency will always give you an edge on broadband phase noise. ADEV / short term stability is linked to the Q

Re: [time-nuts] 10MHz to 25MHz

Hi What are you going to use the 25 MHz for? Will it drive any sort of radio? If so, cleaning up the phase noise of the GPSDO is a *very* good idea. With a PLL, you can *subtract* noise. With a multiplier you can only *add* noise. The narrow bandwidth PLL combined with a low nose VCXO is your

Re: [time-nuts] Thunderbolt Harmonics

Hi > On Jan 18, 2017, at 1:08 PM, jimlux <jim...@earthlink.net> wrote: > > On 1/18/17 8:56 AM, Bob Camp wrote: >> HI >>> >>> the first time we ran the test (using a Keysight 33622 signal >>> generator) we saw significant 2nd and 3rd harmonics (50-

Re: [time-nuts] PN/AM and 1.5Hz spur from frequency doubling?

Hi Without seeing the circuit involved it’s a bit tough to guess all of the possible things that might be happening. One branch leads off to things like the circuit it’s self oscillating and creating the spur. Sub branches involve oscillation in a regulator at low frequency vs RF oscillation

Re: [time-nuts] Thunderbolt Harmonics

HI > On Jan 18, 2017, at 9:44 AM, jimlux wrote: > > On 1/18/17 4:33 AM, Artek Manuals wrote: >> R >> >> Is what your seeing a harmonic (2nd? 3rd?) or a spur i.e what frequency >> is the "harmonic" ? >> >> How are you measuring this ? (Spectrum analyzer ? make/model?) >>

Re: [time-nuts] How to create a super Rb standard

me that's why the Rb > clocks are more stable than Cs clocks on the GPS satellites. > > LiAng > > ---Original--- > From: "Bob Camp"<kb...@n1k.org> > Date: 2017/1/17 21:20:23 > To: "Discussion of precise time and frequency > measurement"<t

Re: [time-nuts] Thunderbolt Harmonics

Hi If you look at the FCC transmitter regs, -60 dbc is “ok” for many transmitters. Bob > On Jan 17, 2017, at 9:40 PM, Rhys D wrote: > > Hi all, > > Before I start, let me say I'm rather a newbie at this sort of stuff so > please be gentle. > > I was looking at the output

Re: [time-nuts] time-nuts Digest, Vol 150, Issue 36

gt; 14. TICC update? (Scott Newell) >> 15. Re: Low CostTemperature sensor (Bill Hawkins) >> 16. Re: Looking for GPS module (Exactime ET6000/Datum 9390-6000) >> (ziggy9+time-n...@pumpkinbrook.com) &g

Re: [time-nuts] How to create a super Rb standard

Hi Since the physics package in the small Rb’s is different than the stuff in the large units, you have some basic limits on what you can do to improve them. The main things people have done are to modify them to turn off the temperature compensation and replace it with some sort of precision

Re: [time-nuts] time transfer over wifi

Hi Ok, that’s a pretty good paper. At least it shows data and digs into the details. It also would lead one to believe that a “Time Nuts” grade sync system might be a hackable sort of thing …… hmmm…..Given how highly integrated these WiFi chip sets have become, that probably is a fantasy.

Re: [time-nuts] wifi with time sync

; > On 1/15/17 6:27 AM, Bob Camp wrote: >> Hi >> >> >> Again, this is why the interest in “how the heck did they accomplish it? >> With the claim of microsecond level performance, they must have run >> into all these issues. > > or is it "with

Re: [time-nuts] wifi with time sync

ake-up calls or application-layer keepalives > to bring VPN tunnels "Back to life" (otherwise the first UDP packets are > dropped). > > Tim N3QE > > > > On Sat, Jan 14, 2017 at 2:02 PM, Bob Camp <kb...@n1k.org> wrote: > >> Hi >> >>

Re: [time-nuts] wifi with time sync

Hi Again, this is why the interest in “how the heck did they accomplish it? With the claim of microsecond level performance, they must have run into all these issues. Just a note: any time I want to do anything that matters, I put it on 5 GHz. There are still issues, but not quite as

Re: [time-nuts] wifi with time sync

Hi Maybe the magic stamping has been hiding in the chips all along. What’s pretty clear is that if it’s there, it’s well hidden …. Bob > On Jan 14, 2017, at 7:04 PM, jimlux <jim...@earthlink.net> wrote: > > On 1/14/17 3:32 PM, Bob Camp wrote: >> Hi >> >>

Re: [time-nuts] wifi with time sync

hardware. Until that’s all up and running you don’t get the new timing stuff. Based on what I see, there’s not a lot of hope for it otherwise. Bob > > On Sat, Jan 14, 2017 at 3:35 PM, Bob Camp <kb...@n1k.org> wrote: > >> Hi _

Re: [time-nuts] wifi with time sync

Hi Here’s what I am seeing: 64 bytes from 192.168.2.2: icmp_seq=3700 ttl=64 time=5.025 ms 64 bytes from 192.168.2.2: icmp_seq=3701 ttl=64 time=4.579 ms 64 bytes from 192.168.2.2: icmp_seq=3702 ttl=64 time=1.511 ms 64 bytes from 192.168.2.2: icmp_seq=3703 ttl=64 time=1.601 ms 64 bytes from

Re: [time-nuts] wifi with time sync

Hi > On Jan 14, 2017, at 1:38 PM, Chris Albertson <albertson.ch...@gmail.com> > wrote: > > On Sat, Jan 14, 2017 at 7:46 AM, Bob Camp <kb...@n1k.org> wrote: > >> Hi >> >> Ok, what I see is that every few hours, I get a “rogue delay” on a single &g

Re: [time-nuts] wifi with time sync

ip:icmp:data] >[Coloring Rule Name: ICMP] >[Coloring Rule String: icmp || icmpv6] > Ethernet II, Src: Actionte_1a:57:9e (00:26:b8:1a:57:9e), Dst: > Apple_a2:57:7b (a8:8e:24:a2:57:7b) > Internet Protocol Version 4, Src: 192.168.1.1, Dst: 192.168.1.10 > Internet Control Message Pr

Re: [time-nuts] wifi with time sync

Hi > On Jan 14, 2017, at 12:44 PM, jimlux <jim...@earthlink.net> wrote: > > On 1/14/17 8:35 AM, Bob Camp wrote: >> Hi >> > >> >> I also believe that ping data is one way to come up with an upper bound on >> just how awful WiFi timing can be.

Re: [time-nuts] wifi with time sync

now what forum to send you to for "weird wifi problems"; there > is probably no good one, because it is a very common consumer problem :( ] > > NTP was mentioned because you (Bob Camp) had not defined the problem > very

Re: [time-nuts] wifi with time sync

linear supply ovens were easy to deal with because they > presented a strong CW signal that drifted around as voltage, load, > and temperature changed. The switcher ovens simply splatter the > whole ISM band with strong microwave noise. > > -Chuck Harris > > Bob Camp wrote: &g

Re: [time-nuts] wifi with time sync

of that issue. I’d still love to know if this magic protocol is simply giant buffers and some sort of tagging or if they do something more interesting. Bob > On Jan 14, 2017, at 12:32 AM, Chris Albertson <albertson.ch...@gmail.com> > wrote: > > On Fri, Jan 13, 2017 at 1:1

Re: [time-nuts] wifi with time sync

sure it’s true in this case. Bob > On Jan 13, 2017, at 4:07 PM, John Hawkinson <jh...@mit.edu> wrote: > > Bob Camp <kb...@n1k.org> wrote on Fri, 13 Jan 2017 > at 15:35:19 -0500 in <adce3c3b-a84f-4f78-93b0-824f5a9b4...@n1k.org>: > >> What standard

Re: [time-nuts] wifi with time sync

ver the network and the > reference clocks might be thousands of miles away. So you might want to > run one on say your wifi router or a local computer with hardwire > connection to the router then you'd see the effect of only your wifi. > > > > On Fri, Jan 13, 2017 at 12:35

Re: [time-nuts] wifi with time sync

the network and the > reference clocks might be thousands of miles away. So you might want to > run one on say your wifi router or a local computer with hardwire > connection to the router then you'd see the effect of only your wifi. > > > > On Fri, Jan 13, 2017 at 12:35 PM,

Re: [time-nuts] wifi with time sync

p talking about pings? > > Bob Camp <kb...@n1k.org> wrote on Fri, 13 Jan 2017 > at 15:12:38 -0500 in <c88c78a6-a015-4dcc-9e23-394dc33a3...@n1k.org>: > >> I’m sure you are right about the response time. Right now the >> variation is running almost 3 ms at on

Re: [time-nuts] wifi with time sync

On Fri, January 13, 2017 11:40 am, Bob Camp wrote: >> The ping response is anywhere from 2 ms out to 400 ms. Most of >> the time it's in the 3 to 9 ms range. Simply taking that >> down to < 1 us would be a really big deal. > > I doubt that the response time will get that

Re: [time-nuts] Thermal effects on cables --> ADEV

"moving 300 > pt ADEV" when continously monitoring a (pair of) frequency source in e.g a > VLBI site - the reason for limiting it to 300 pts being that much more than > that is likely to average out potential issues.. > > Does that make sense? > >> Den 1

Re: [time-nuts] wifi with time sync

of timing things as well. Bob > On Jan 13, 2017, at 1:08 PM, Denny Page <de...@cococafe.com> wrote: > >> On Jan 13, 2017, at 09:40, Bob Camp <kb...@n1k.org> wrote: >> >> Just for reference, I happen to be running a ping over my local WiFi to one >> of the

Re: [time-nuts] Thermal effects on cables --> ADEV

think you might be overthinking their point, that if you plan to use an > xDEV as a measure for state of health, don't use years worth of data. > Otherwise it could be days before the xDEV visually changes. > > On Fri, Jan 13, 2017 at 11:04 AM, Bob Camp <kb...@n1k.org> wrote: >

Re: [time-nuts] wifi with time sync

Hi Just for reference, I happen to be running a ping over my local WiFi to one of the switches on the LAN. The ping response is anywhere from 2 ms out to 400 ms. Most of the time it’s in the 3 to 9 ms range. Simply taking that down to < 1 us would be a really big deal. Bob > On Jan 13,

Re: [time-nuts] wifi with time sync

Hi A lot depends on how much “less than a microsecond” the chip sets really deliver in the real world. If they get down into the sub 100 ns range (which they might), it’s a very useful thing for relaying GPS data from a roof antenna down to an NTP server in the basement. 1588 is a “less than a

Re: [time-nuts] Thermal effects on cables --> ADEV

Hi There’s an interesting comment buried down in that paper about limiting ADEV to < 300 samples per point. Their objective is apparently to better highlight “systematic errors”. I certainly agree that big datasets will swamp this sort of thing. I’m not quite sure that I’d recommend ADEV to

Re: [time-nuts] General questions about making measurements with time interval counter.

is to decimate the sample set. Bob > Or is that some other *DEV? My point is that for 1801 seconds, aren't there > a lot more than 18 samples put in the 100S bin? And I've probably stated > that incorrectly, too. > > Bob > > > From: Bob Camp <kb...@n1k.org&g

Re: [time-nuts] General questions about making measurements with time interval counter.

to share them with someone. > > Bob - > AE6RV.com > > GFS GPSDO list: > groups.yahoo.com/neo/groups/GFS-GPSDOs/info > > From: Bob Camp <kb...@n1k.org> > To: Bob Stewart <b...@evoria.net>; Discussi

Re: [time-nuts] General questions about making measurements with time interval counter.

e? > > Just for grins, I also included a screencap of the phase points. > > Bob - > AE6RV.com > > GFS GPSDO list: > groups.yahoo.com/neo/groups/GFS-GPSDOs/info > > From: Bob Camp <kb...@n1k.org&g

Re: [time-nuts] General questions about making measurements with time interval counter.

Tom, in orange, using his H Maser and a > Timepod to show how poor the 5370 is compared to the Timepod below about 60S > tau. These are essentially apples vs apples tests. > > Bob > > > > > From: Bob Camp <kb...@n1k.org> > To: Discussion of precise time and

Re: [time-nuts] General questions about making measurements with time interval counter.

12, 2017, at 4:36 AM, Dr. David Kirkby (Kirkby Microwave Ltd) > <drkir...@kirkbymicrowave.co.uk> wrote: > > On 12 January 2017 at 02:31, Bob Camp <kb...@n1k.org> wrote: > >> Hi >> > > Hi Bob > > >> >> The most basic issue you a

Re: [time-nuts] General questions about making measurements with time interval counter.

Hi The most basic issue you are going to run into is that your counter is not high enough resolution / accuracy to give you meaningful data for time intervals under a few hundred seconds. I would focus on improving on that part of things before I went off on a major “test everything”

Re: [time-nuts] hm H Maser

Hi The obvious question would be: What does it cost to set up a line to make a proper set of spherical Rb cells? Doing this as a glassblowing project is a dead end. You need it properly tooled …. Bob > On Jan 11, 2017, at 7:05 PM, Bruce Griffiths > wrote: > >

Re: [time-nuts] hm H Maser

Hi > On Jan 11, 2017, at 6:07 PM, Angus wrote: > > On Tue, 10 Jan 2017 21:43:07 -0500, you wrote: > >> >> This does get back to “state of the art Rb” and what that means. In my >> suggested case that’s measured in terms of ADEV for Tau = 1 to 1,000,000 >> seconds.

Re: [time-nuts] hm H Maser

sible as its > already been done as part of a PhD thesis.Using as large a cavity as possible > is probably useful so that a large cell can be employed.What resonant mode is > desirable in the cavity?Do we need to avoid field reversal as in the hydrogen > m

Re: [time-nuts] hm H Maser

Hi A cryo pump will get you into reliability issues if run 24/7. It also is doubtful that you will be able to maintain the vacuum level over long periods. Bob > On Jan 11, 2017, at 12:09 AM, Bruce Griffiths > wrote: > > One could always use a cryo pump. > The

Re: [time-nuts] hm H Maser

.co.nz> > wrote: > > A possible RF chain for a Rubidium standard using off the shelf parts plus a > couple of custom microwave filters:https://arxiv.org/pdf/1204.4215.pdf > > Bruce > >On Wednesday, 11 January 2017 2:10 PM, Bob Camp

Re: [time-nuts] hm H Maser

Hi The gotcha is that 5065’s never were a popular item in HP’s lineup. As a result, they are fairly sparse in the surplus market. Those who need them for this or that application gobble them up on a regular basis. Trying to do up a couple hundred “improved” 5065’s just isn’t going to happen (at

Re: [time-nuts] hm H Maser

Hi > On Jan 10, 2017, at 2:45 AM, Dr. David Kirkby (Kirkby Microwave Ltd) > <drkir...@kirkbymicrowave.co.uk> wrote: > > Once 9 Jan 2017 12:59, "Bob Camp" <kb...@n1k.org> wrote: >> >> Hi >> >> Ok here are some rough numbers: &g

Re: [time-nuts] hm H Maser

Hi Ok here are some rough numbers: > On Jan 9, 2017, at 4:35 AM, Dr. David Kirkby (Kirkby Microwave Ltd) > <drkir...@kirkbymicrowave.co.uk> wrote: > > On 8 Jan 2017 17:34, "Bob Camp" <kb...@n1k.org> wrote: > >> You are talking about a project t

Re: [time-nuts] hm H Maser

(These can >> easily be constructed from commercially available parts) and improve >> somewhat on the performance (The oven design of most commercial > ECDLs seems >> suboptimal). Bruce >> >>On Monday, 9 January 2017 10:23 AM, Bob Camp <kb

Re: [time-nuts] hm H Maser

Hi > On Jan 8, 2017, at 11:57 AM, William H. Fite wrote: > > Bob, I think you're missing the point here. This is not the quest for > utimate standards of accuracy/precision/resolution, it Is not about > economic viability, or even attainability, let alone being "worth the >

Re: [time-nuts] hm H Maser

Hi > On Jan 8, 2017, at 11:21 AM, Dr. David Kirkby (Kirkby Microwave Ltd) > <drkir...@kirkbymicrowave.co.uk> wrote: > > On 8 January 2017 at 15:22, Bob Camp <kb...@n1k.org> wrote: > >> Hi >> >> I guess the question then would be: >> >&

Re: [time-nuts] hm H Maser

Hi I guess the question then would be: Is a H Maser that runs 6.6 x 10^-12 at 1 second worth the trouble? With 100 KHz / C temperature coefficients running around, getting good stability in a real world setting at 1 day will be “interesting”. Just for reference: The MH-2010 data sheet

Re: [time-nuts] Survey plot as art.

difference in the receiver, perhaps in the math? > > Pete. > > On 1/7/2017 4:16 PM, Bob Camp wrote: >> Hi >> >> In terms of multipath at GPS frequencies, a couple of inches is a *lot*. >> Also unless you have >> pretty good antennas (as in much larger th

Re: [time-nuts] Survey plot as art.

:00 PM, Gary E. Miller <g...@rellim.com> wrote: > > Yo Bob! > > On Sat, 7 Jan 2017 15:16:34 -0500 > Bob Camp <kb...@n1k.org> wrote: > >> The “simple” answer is that the weird legs going out from the central >> blob are the result of multi-path / refle

Re: [time-nuts] Survey plot as art.

Hi The “simple” answer is that the weird legs going out from the central blob are the result of multi-path / reflections in the received signal. With enough data you might be able to correlate them to observed obstructions. The simulation modeling required to make that happen might be a bit

Re: [time-nuts] σ vs s in ADEV

HI > On Jan 5, 2017, at 6:33 AM, Magnus Danielson > wrote: > > Hi, > > On 01/05/2017 01:26 AM, Tom Van Baak wrote: >> Hi Attila, >> >> The plain ADEV calculation is essentially a measure of unexpected or >> unwanted drift in frequency; which is the 1st difference

Re: [time-nuts] Line Voltage - USA

Hi > On Jan 4, 2017, at 3:42 AM, Hal Murray wrote: > >> Did the utility replace the damaged equipment? > > A friend lived in a building when the city crew working on a transformer put > 440 on the line. It blew out all the electronics in 12 condos - mostly TVs. > I

Re: [time-nuts] Line Voltage - USA

HI > On Jan 3, 2017, at 6:59 PM, Hal Murray wrote: > > > kb...@n1k.org said: >> They sell a lot of 24 bit audio DAC’s into that sort of gear. Team them up >> with some DSP and you get all sorts of interesting data. The “one number” >> that counts is the fundamental ….

Re: [time-nuts] Line Voltage - USA

Hi Measuring line voltage for “official” purposes straight up with a lab grade device that may have a bandwidth of many KHz (or even 100’s of KHz) is generally not a good way to go. The line voltage is the value of the fundamental (50 or 60 Hz) sine wave. All the other nonsense that

Re: [time-nuts] Temperature (environmental) sensors

it all in a some large form factor. Bob > On Jan 3, 2017, at 12:54 PM, jimlux <jim...@earthlink.net> wrote: > > On 1/3/17 9:15 AM, Bob Camp wrote: >> Hi >> >> There is an ever increasing pool of good sensors to put into something like >> this. >> (M

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