[time-nuts] Terrestrial Tides and Land Movement

I did some idle searching trying to see if there was a relationship between terrestrial tides and timing receivers. I couldn't find anything useful, but I did discover that the Jersey Village area, about 2 miles northeast of me, is sinking about 2 inches a year.  So, my question is what effect

[time-nuts] New 5370A

I got a new 5370A, so of course I've been running a bunch of tests on it.  In the image linked below, the start channel is my PRS-45A, the stop channel is my GPSDOe (e is for engine) and the ARM channel is fed by the PPS from my SSR-6Tru.  As you can see in the notes, the test parameters are

[time-nuts] Trimble 65256 OCXO info?

Does anyone have any information about the Trimble 65256 OCXO?  I bought one recently and hooked it up to 12V per the vendor.  (Yeah, I know.)  Although it worked, it set off such a stench: the usual electronics burning up, give you a sore throat smell.  So, I got a replacement and same thing. 

[time-nuts] Controlling the 5370A via GPIB

I need to capture the time between the PPS and the OCXO on my GPSDO to fine-tune my calibration curve.  I'm having good luck doing this with my 5335A, which of course, has less resolution than my 5370A.  But, when I setup the 5370A with what I think is the right setup, every 6th or 7th value is

Re: [time-nuts] Terrestrial Tides and Land Movement

Hi Bob, How is this achieved?  Is there a coupled dead-reckoning system that updates the timing location, or something else? Bob From: Bob Camp kb...@n1k.org To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, May 25

Re: [time-nuts] Terrestrial Tides and Land Movement

Tom said: The nice thing about GPS, unlike other time transfer methods, is that can handle the case of a moving antenna. As the antenna moves so does the time. This is why GPS timing receivers work (almost as well) on top of your car as on top of your house. I don't get that.  What's the

Re: [time-nuts] Terrestrial Tides and Land Movement

in 3-D and see what difference there is in RMS timing residuals (or in ADEV). I wonder if your GPSDO can even measure the difference. /tvb - Original Message - From: Bob Stewart b...@evoria.net To: Discussion of Precise Time and Frequency Measurement time-nuts@febo.com Sent: Monday, May

Re: [time-nuts] Terrestrial Tides and Land Movement

located in a position suitable for precision timing.  The power of the HOA is not to be trifled with.  That, and the sky is full of power lines and other junk around here. Bob From: Bob Camp kb...@n1k.org To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement

[time-nuts] U-Center issue vs LEA-6T

I've been doing some tests on my GPSDO with the LEA-6T location deliberately set somewhere far away.  I had U-Center V8.17 running and connected to the receiver.  During some of those tests, the CFG-TMODE mode switched from Fixed Mode to Disabled without any commands from me.  As a result, the

Re: [time-nuts] I've designed a GPSDO, but how good is it?

Hi Nick, In fact, if no-one else has volunteered, contact me offline and I'll run a test for you on my equipment, which is an HP5370A and a Symmetricom PRS-45A Cesium standard.  bob at evoria dot net From: Tom Van Baak t...@leapsecond.com To: Discussion of precise time and frequency

Re: [time-nuts] Data Collection for Allan Deviation

Hi Bob, I believe that the approach I used in the example plot I linked in the other post was PPS to ext/arm, GPSDO 10MHz to start, Cs 10MHz to stop.  So, is this a methodology issue, then? Bob From: Bob Camp kb...@n1k.org To: Bob Stewart b...@evoria.net; Discussion of precise time

Re: [time-nuts] Data Collection for Allan Deviation

...@phk.freebsd.dk To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, August 1, 2015 4:10 PM Subject: Re: [time-nuts] Data Collection for Allan Deviation In message 1925117252.232793.1438455428192.javamail.ya...@mail.yahoo.com

Re: [time-nuts] Data Collection for Allan Deviation

Hi Poul, 0)  Make sure that the counter does not get its reference frequency     from any of the input signals. Does your rule 0 hold if one of the input signals is a Cs standard?  I believe I've posted in the past that the ADEV from 1 tau to 100 tau is a bit noisy if I use the internal 10811 to

[time-nuts] GPSDO question

Speaking with Tom recently impressed on me just how much I don't know about what's normal for a GPSDO.  The options on the LEA-6T are formidable and have consequences for my GPSDO.  The question I'm struggling with now is what's normal during the survey process?  The only example of a

[time-nuts] Ublox LEA-6T CFG-PRT command question

I want to change the UART1 port speed on my LEA-6T via message string from my GPSDO board.  I had assumed that I would have to discover (or know) the baud rate already set on the LEA-6T in order to change it.  But it appears that the LEA-6T can receive messages at any baud rate, but you need to

Re: [time-nuts] Looking for Datum/Symmetricom MONITOR.EXE software

Hi Skip, You might try contacting Symmetricom directly.  That's how I got my copy of monitor3.exe for my PRS-45A.  You can change the baudrate etc on monitor3.exe. Bob From: Skip Withrow To: time-nuts Sent: Thursday, October 29, 2015 9:18

Re: [time-nuts] Time syncing WiFi routers using FM radio

Hi Mark, What's the inherent problem with the idea?  In the early days of radio, they used commercial radio transmissions as an encryption mechanism, so there is some history of using commercial radio as a reference source.  Is it simply a matter of different propagation delays and multi-path

Re: [time-nuts] Beginners GPS locked frequency counter question

Tom, It's been awhile since I did soundcard SSTV, but the program MMSSTV uses the time ticks from WWV to do a calculation similar to what you describe.  You tune in WWV on your receiver, which is coupled to your computer's soundcard.  The MMSSTV calibration routine puts a raster scan on the

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

Synergy GPS makes an SSR-6Tr board that speaks Motorola binary and would probably work in the KS-24361.  It's on an M12+ sized board, so you'd also need their adapter board to fit it in.  Their SSR-M8T board would probably do the same thing but using an LEA-M8T receiver.  I believe they're

Re: [time-nuts] Lucent RTFG-u DE-9 connectors

Hi Alex, It's called a slidelock.  Here's the link I posted last time this came up.  Look at the bottom right. http://www.mouser.com/catalogviewer/default.aspx?page=1605=706-160X10689X=en-US=647 Bob From: Alexander Huemer To: time-nuts@febo.com Sent: Thursday,

Re: [time-nuts] Number of GPS sats in the sky?

Thanks Chris and everyone else who responded.  I just didn't know what to look for.  The full 36 shouldn't take up all that much memory. Bob From: Chris Hoffman cq.k...@gmail.com To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com

[time-nuts] Number of GPS sats in the sky?

Is there a practical limit to the number of GPS sats overhead at any one time? I ask this because I'd like to start parsing this info from my ublox receiver and need to setup an array for the values.  Memory is not unlimited on my PIC. Bob - AE6RV

Re: [time-nuts] Einstein Special on PBS

of spaghettification, or course.)  But generations of people back on earth would live and die for each tick of your watch. Bob From: Mike Feher <mfe...@eozinc.com> To: 'Bob Stewart' <b...@evoria.net>; 'Discussion of precise time and frequency measurement' <time-nuts@febo.com&

Re: [time-nuts] Einstein Special on PBS

Hi Mike, I'm far from an expert on this, but what you're missing is that time and space isn't the same between any two points that are located in different gravity gradients and/or moving at different relative velocities.  The hyperfine transitions are happening at the same local rate whether

Re: [time-nuts] DMTD - analog multiplier vs. diode mixer ?

Hi Bruce, Thanks a LOT for your response to Poul's query!  I've been searching for DMTD info for a few some time now, and I haven't come up with a lot.  Searching for "CERN White Rabbit" got me more in a few minutes than I've found in months.  Like Poul, I've become interested in building a

Re: [time-nuts] Einstein Special on PBS

Hi John, I hadn't run into this idea before, and I like it.  But I have a problem with the statement:.  "If you move through space at 100,000,000 meters per second in space, then your velocity in the t direction is 283,000,000 meters per second (because sqrt(100E6^2 + 283E6^2) = 300E6.)"  The

Re: [time-nuts] Commercial software defined radio for clock metrology

Hi Bruce, What about the BeMicroCV-A9 that Scotty Cowling has been recommending in QEX? It has a Cyclone V SoC FPGA running at 800MHz. Installments to his series have been slow coming, but I've been wondering if this could be the basis for a Timepod type of unit. Bob

Re: [time-nuts] Ublox Neo-6M time error.

Hal, thanks for reminding me of what I ran into on the LEA-6T modules. When you first power them on, they are often a second off in time. It's not until the NAV-TIMEUTC->valid field returns a set validUTC flag that the time can be counted on. But it usually doesn't take more than a minute or

Re: [time-nuts] OT stuffing boards: was GPS interface/prototyping board

I've given thought to stencils, but without building something to prop my hands on, I'll smear the paste. So, I place up to 10 or 15 parts at a time and use the hot-air gun. To each his own, I guess. Bob --- GFS

Re: [time-nuts] OT stuffing boards: was GPS interface/prototyping board

[time-nuts] OT stuffing boards: was GPS interface/prototyping board To: "Bob Stewart" <b...@evoria.net>, "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Date: Thursday, June 23, 2016, 5:27 PM Hi Around here, assuming: 1)

[time-nuts] OT stuffing boards: was GPS interface/prototyping board

One more related question before this topic dies, if you don't mind. What about the other side of building: stuffing the boards. My GPSDOs have about 120 parts per board, plus some custom work on the SMA connectors. Is there a service out there that will populate boards with SMT components

Re: [time-nuts] OCXO noise as they retrace

Thanks Bob.  That makes sense.  --- GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time a

Re: [time-nuts] OCXO noise as they retrace

Hi John, That is a thought.  The 1s ADEV had been very stable across units until just now.  But, I don't know how to look at the beam current.  There is a "Monitor3" program that I can use (see link below) that can plot the Clock Servo values, as well as Zeeman Servo, Gain Servo, CBT Supplies,

[time-nuts] OCXO noise as they retrace

I've had a specific GPSDO running for some time now, and I notice that the noise at tau 1s has gotten worse as the retrace flattens out.  In this case, the  ADEV was about 3.6E-11 a month or so ago, and has now gone up to about 8.5E-11.  (Measurements performed by a 5370A against a PRS-45A Cs

[time-nuts] OCXO Retrace

I've been running up a number of OCXOs lately, all Trimble 34310-T. For most of them, the DAC moves in the negative direction after lock. But there are a few where the DAC moves more positive. Is this an indication of a different cut of crystal, or is retrace direction more or less random?

Re: [time-nuts] OCXO Retrace

built only a limited number of these units. The normal situation is to retrace downward from the start, once initial warmup is over. Bob On Wed, 2/10/16, Tim Shoppa <tsho...@gmail.com> wrote: Subject: Re: [time-nuts] OCXO Retrace To: "

Re: [time-nuts] LIGO detects gravitational waves

Hi Tom, Thanks for posting this. I'm looking at the timelab plot, and the only thing I can relate that to is a musical note played backward. IOW, the decay seems backwards to me. Bob - AE6RV On Sat, 2/13/16, Tom Van Baak

Re: [time-nuts] Generating a solid PPS from 10Mhz source

Hi Poul, Your comment about on-chip PLLs got me to wondering about the dsPIC33FJ128MC804 I'm using in my GPSDO. So, I put it on the 5370A to see what's up. Input to the gate port is the drive signal for an LED that I flash at 1PPS (controlled by an on-chip timer). I delay that with a 10ft

Re: [time-nuts] MTI 260-0624-D OCXO

Hi Bob, I've had essentially the same experience with a batch of 34310-Ts that I got from China. Some are very good, most are good enough, some work but are useless for anything serious. I haven't gone through enough of them to get any feel for the waste rate. Hopefully it won't be more

Re: [time-nuts] OCXO Retrace

Hi Charles, I'll see if I can figure out which of these is retracing the "wrong" way and put it in a unit. I'll let it cook for a couple of days and then post a plot. Like I said, these are all Trimble 34310-T, though I know that there were at least two manufacturers for that part number.

[time-nuts] 10MHz to PPS

Has anyone coded a PICDiv type of solution into a dsPIC33F chip using a 32-bit Type B timer? I've been doing some experimentation over the past few days, and I've had a few latency issues when using the internal clock, which is PLL linked to the 10MHz external clock input. The problem shows

[time-nuts] LEA-M8T

I recently bought a number of LEA-M8T receivers and I have to say that I am unimpressed, so far. They don't survey to the same reported accuracy as the LEA-6T in the same amount of time. They certainly aren't better in the jitter after sawtooth correction. So, have I managed to overlook some

Re: [time-nuts] GFS-6A - was: Advise on building a DIY GPSDO?

Hi Charles, I've changed the subject line, so I hope this isn't perceived as a thread-jack. It's always dangerous to post anything substantive to this list, but I think it's about time. Here's a timelab file of my GPSDO, which I've been working on for quite some time with help from Dan K and

Re: [time-nuts] LEA-M8T

, many data structures. Bob On Wed, 4/6/16, Logan Cummings <logan.cummi...@gmail.com> wrote: Subject: Re: [time-nuts] LEA-M8T To: "Bob Stewart" <b...@evoria.net>, "Discussion of precise time and frequency measurement&

Re: [time-nuts] Cheap LEA-6T [was: Re: Precise Time transfer and relative position over ashort baseline]

Hi Attila, The two versions of the -6T I have experience with - LEA-6T-0-001 and LEA-6T-1-000 - have both had a single shield. So, that implies that these are at least 2 steps older than what's out now. The price? They must be getting them at or near single digits USD. Bob

Re: [time-nuts] 5370A clock buffer board jitter/noise?

revert it, so that is at least one thing to test. Cheers, Magnus On 03/23/2016 04:37 AM, Bob Stewart wrote: > I started getting noise spikes of up to 500ps on my 5370 the other day.  When I switch to external clock and use the PRS-45A, the noise goes away.  In fact, the noise issue is w

Re: [time-nuts] Spectrum Analyzer Specifications

Hi Bob, Could you use a gate instead of an amp? Bob On Thu, 3/24/16, Bob Camp wrote: Subject: Re: [time-nuts] Spectrum Analyzer Specifications To: "Discussion of precise time and frequency measurement" Date:

[time-nuts] 5370A clock buffer board jitter/noise?

I started getting noise spikes of up to 500ps on my 5370 the other day. When I switch to external clock and use the PRS-45A, the noise goes away. In fact, the noise issue is way better than with the 10811. I swapped in a different 10811, and the noise doesn't seem to have returned, but it

Re: [time-nuts] Advise on building a DIY GPSDO?

As a victim of the "I'm gonna build a GPSDO" virus, I think the cautions are well worth mentioning. Building a decent GPSDO sounds like such a simple thing, but it slowly turns into a rabbit hole as you discover you need ever better test equipment, and a microscope, and hot air rework station,

Re: [time-nuts] A new member & PN test set

Hi Oleg, I'm interested in your PN test set. I'm sure a number of us are. If you have webpages or documents up, could you share them with the list? Otherwise, could you email me direct?bob at evoria dot net Bob On Sun, 3/27/16, Oleg Skydan

Re: [time-nuts] RG6 or LMR400 for GPS Antenna (Symmetricom 58532A and T-bolt)

Hi Ryan, For the few years I've been on time-nuts, I understood the consensus view to be to get a good quality RG-6QS satellite cable. A few of the posts in this thread have made me wonder if the consensus is changing, or if it's just too much trouble to stand up to the crowd. I've got about

Re: [time-nuts] RG6 or LMR400 for GPS Antenna (Symmetricom 58532A and T-bolt)

th? I know I can figure that out with an SG and Scope, assuming the propagation delay is what the spec sheet claims to be (most RG6 seems to be right around 80%) (the home depot stuff seems to be 79%). > > -Ryan Stasel > >> On Apr 22, 2016, at 14:38 , Bob Stewart <b...@ev

Re: [time-nuts] Optical transfer of time and frequency

I apologize for not following the original thread closely, but has anyone mentioned The White Rabbit Project? Here's a wiki link. Links from there to CERN, etc. It might be beyond budget, etc. en.wikipedia.org/wiki/The_White_Rabbit_Project Bob On

[time-nuts] Last Call Group Buy Ublox LEA-6T

Hi guys, This is the last call for the group buy of the Ublox LEA-6T modules. Just be be sure you know what you're getting: these are new in package LEA-6T modules. They are not on a breakout board of any type. I have the following names and quantities. If your name is not on this list,

Re: [time-nuts] GENIUS by Stephen Hawking (PBS TV), with 5071A cesium clocks

If you're using someone else's clock (e.g. GPS time) then it doesn't matter what's happening to you, you'll only know what you see on that clock. But, if you have your own clock (e.g. an HP 5071A) on your person, and can compare it to someone else's clock, then assuming both clocks are

Re: [time-nuts] New Product Release - GPSDO Frequency Standard

elease - GPSDO Frequency Standard To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Date: Thursday, May 19, 2016, 12:14 AM Hoi Bob On Thu, 19 May 2016 01:11:32 + (UTC) Bob Stewart <b...@evoria.net> wrote: > It's time I got off the

[time-nuts] New Product Release - GPSDO Frequency Standard

Hi guys, It's time I got off the dime and did a product release of my GPSDO. My mission in creating this unit was to provide a stable and accurate frequency reference with 10Mhz, 5Mhz, and 1Mhz outputs. It does have a PPS output, but that is directly from the Ublox receiver, and is not

[time-nuts] DMTD was: high rev isolation amps

Hi Bob et al, I'm finally drawing up a schematic for a DMTD and I thought I'd use the NBS circuits for a lot of it. So, how about PZT3904 transistors in the isolation amps? They're in SOT-223 with the heat sink tab. I figure to use some version of the TUF-1 for the DBMs. The first version

Re: [time-nuts] DMTD was: high rev isolation amps

, 5/11/16, Bob Camp <kb...@n1k.org> wrote: Subject: Re: [time-nuts] DMTD was: high rev isolation amps To: "Bob Stewart" <b...@evoria.net>, "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Date: Wednesday, May 11, 2016, 8:44 PM

Re: [time-nuts] DMTD was: high rev isolation amps

gh rev isolation amps To: "Bob Stewart" <b...@evoria.net>, "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Date: Wednesday, May 11, 2016, 10:33 PM For DMTD service with an offset frequency of 100Hz or less the flicker phase noise o

Re: [time-nuts] FS HP 5335A

Hi, I know this is a for sale post, but there's a jumper that needs to be there to work with the regulator oscillator. Page 2-4 of the Operating and Service Manual (05335-90021) details the instructions for installing the Option 010, the 10811 OCXO. Instruction "c" is below. You'd need to

Re: [time-nuts] uBlox (US) reseller recommendation?

I'm going to be ordering more than 10 soon, so I can be the focus of a group order. If everyone who wants a few could email me offline, we'll work out the particulars. Bob On Mon, 5/16/16, Jay Grizzard wrote:

[time-nuts] Lea-6T Math error?

I hope I haven't posted about this before, but it's something that's bugged me for awhile. When I run a survey-in on an LEA-6T, the CFG-TMODE2->fixedPosAcc value seems to be wrong. For instance, I ran a survey today and told it to run for 32,400 seconds and reach at least 350mm accuracy.

Re: [time-nuts] How to achieve best results from U-Blox survey-in

Hi Neil, Yes, disable all except GPS sats. Also, turn off SBAS, set your max and min number of sats (defaults are probably what you want), and the satellite elevation mask. The elevation mask defaults to 5, but can you really see that low? There are different ideas about how long to run the

Re: [time-nuts] How to achieve best results from U-Blox survey-in

n, 5/8/16, Pete Stephenson <p...@heypete.com> wrote: Subject: Re: [time-nuts] How to achieve best results from U-Blox survey-in To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Date: Sunday, May 8, 2016, 3:32 PM On Sun, May 8, 2016 at 7:25 P

[time-nuts] OCXO phase pops

I started getting phase pops in my testing recently, and I'm pretty sure they're from the PRS-45A Cs standard. Is this likely to go away after it cooks some more, or do I need to start looking for a new OCXO? It's been running since January, and has an MTI marked model number 250-0827. The

Re: [time-nuts] OCXO phase pops

e-nuts@febo.com Cc: mag...@rubidium.se Date: Monday, May 9, 2016, 5:30 AM How does it behave when you run the PRS-45 in open loop? Cheers, Magnus On 05/09/2016 02:43 AM, Bob Stewart wrote: > I started getting phase pops in my testing recently, and I'm pretty sure they're from the P

Re: [time-nuts] The home time-lab

Hi Brooke, Thanks for that info.  I've got the important bits (PRS and GPSDOs) now hooked up to an APC Smart-UPS 700.  What will happen when it goes to battery power, I don't know.  I've been doing qualification testing on a new batch of GPSDOs, so I haven't had time to do any testing of power

Re: [time-nuts] The home time-lab - APC Smart UPS 700

I let an older, well-aged GPSDO warm up overnight and then I ran a test with the UPS.  Attached were the PRS*, the GPSDO, and the 5370A.  I didn't notice anything when I removed power.  I did notice about a 450ps phase spike when I plugged the UPS back in some 640 seconds later.  But that was

Re: [time-nuts] Venus838LPx-T opinions?

In timing mode, you care very much about the quantization error messages. Bob  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Gary E. Miller To: Mark Sims

Re: [time-nuts] LSEM (Leap Second Every Month)

But would it really solve your problems, Jim?  The problem is essentially that periodically, there are two different clock times that represent the same moment in time.  For telescopes, stock markets, spread spectrum, time-based encryption, etc that's a big problem.  Would it not be better to

Re: [time-nuts] Very Accurate Delta Time RF Pulse Measurements

Hi Jerome, This may or may not be of any help, but have you considered using several RTL-SDR devices running at the same time?  You'd need to use a common clock, and probably a number of other enhancements.  But, if you could pull it off, you'd have a wideband RDF type of device.  You'd

Re: [time-nuts] The home time-lab

Charles, I can't speak for Brooke, but I have to point out that each of us has different needs when it comes to powering our lab.  For myself, if I lose power, that's OK.  I'm retired selling a few GPSDOs here and there and working on some other stuff, so I don't need a 24/7 operation.  What

Re: [time-nuts] Adafruit Ultimate GPS timing message arrival times

I liked the Adafruit too when I was using it a couple of years ago, but it did have a bad habit of going walkabout.  Yeah, a lot of that was my antenna, but it's still worth mentioning. Bob - AE6RV.com GFS GPSDO list:

[time-nuts] Low cost SDR suitable for phase noise measurement?

A number of posts have appeared about Zynq SDRs on the "Shera revisited" thread.  So, I'd like to ask the more general question: Are there any low cost SDRs that are suitable for measuring phase noise when coupled with a DMTD?  I believe what I'm looking for is something with enough bits to

Re: [time-nuts] Working with SMT parts.

Hi Bob, You want to get something along the lines of ebay item 272331719376 or 262202931320.  The boom is pretty important, otherwise how do you get your boards under the microscope if they're not very small?  Some time ago, I got a Bausch & Lomb Stereo 3 with 10X oculars and a 0.5 barlow.  The

Re: [time-nuts] Low cost SDR suitable for phase noise measurement?

Hi Brooke, It looks like I've asked a question poorly, yet again.  So, let me try again.  I have this idea of combining a DMTD with an SDR.  So, said that way, it looks like what I really need is a 2-channel audio SDR.  And having said that, maybe what I'm looking for is an external USB sound

Re: [time-nuts] Safely getting the electrical length of a connected antenna feedline

Why is velocity factor an issue?  Aren't we only interested in the electrical time from one end of the coax to the other? Bob  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Didier Juges

Re: [time-nuts] Low cost SDR suitable for phase noise measurement?

arget signal” is in the 1 to 10 Hz range. Is that correct or are you looking for something to use instead of a DMTD? Bob > On Aug 11, 2016, at 3:29 PM, Bob Stewart <b...@evoria.net> wrote: > > Hi Brooke, > It looks like I've asked a question poorly, yet again.  So, let me t

Re: [time-nuts] Low cost SDR suitable for phase noise measurement?

noise. Bob > On Aug 11, 2016, at 5:15 PM, Bob Stewart <b...@evoria.net> wrote: > > Hi Bob, > If I understand the question correctly, yes.  The DMTDs that I've encountered > so far use a zero-crossing detector and a TIC.  I wanted to build sort of a > hybrid system that

Re: [time-nuts] Low cost SDR suitable for phase noise measurement?

att...@kinali.ch> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Thursday, August 11, 2016 5:12 PM Subject: Re: [time-nuts] Low cost SDR suitable for phase noise measurement? On Thu, 11 Aug 2016 19:29:08 + (U

[time-nuts] Syncing Tom's PICDivs to 1PPS

For my next GPSDO board revision, I would like to include one of Tom's PICDiv devices to give a much better 1PPS out than the Ublox receivers are capable of.  This means that it has to be started (or slewed to be) exactly on time.  So I was wondering if anyone had experimented in controlling

Re: [time-nuts] HP5370 power supply measurements

Hi Rami, I am very interested in your 5370 power conversion.  Can you give us any more information as to the model number of the buck regulators you used and where you got them.  Did you run into any problems?  Did you make any notes or drawings? Bob 

Re: [time-nuts] GPS message jitter (was GPS for Nixie Clock)

Interestingly enough, the Ublox LEA series of timing receivers has a USB port which you can connect directly to a USB cable.  Of course you want to use an ESD device, etc. Bob  - AE6RV.com GFS GPSDO list:

Re: [time-nuts] How does sawtooth compensation work?

Hi Nick, Let's use the example of a Ublox timing receiver.  In the TIM-TP data package, there is a qErr value, which is the quantization error of the *next* PPS pulse output by the receiver.  At the next PPS, you would subtract that from the unwrapped phase measurement your GPSDO makes and

Re: [time-nuts] Allan Deviation recipe?

t <time-nuts@febo.com> Sent: Tuesday, July 19, 2016 1:42 PM Subject: Re: [time-nuts] Allan Deviation recipe? Yo All! With help from Tom Van Baak and Bob Stewart, I have 6 weeks worth of GPS Serial and PPS timing data in a nice ADEV chart.  I think. Check it out:     https://rellim.c

Re: [time-nuts] GPS for Nixie Clock

Mark, I see some LEA-6T units and some NEO-M8N units.  Has anyone done any timing tests on these since they came up last time on time-nuts?  The prices just seem to be way on the low side. Bob  - AE6RV.com GFS GPSDO list:

Re: [time-nuts] The home time-lab

/info From: Poul-Henning Kamp <p...@phk.freebsd.dk> To: Discussion of precise time and frequency measurement <time-nuts@febo.com>; Hal Murray <hmur...@megapathdsl.net> Cc: Bob Stewart <b...@evoria.net> Sent: Friday, July 8, 2016 1:52 AM Subject: Re: [time

Re: [time-nuts] The home time-lab

bro...@pacific.net> To: Bob Stewart <b...@evoria.net> Sent: Friday, July 8, 2016 1:13 PM Subject: Re: [time-nuts] The home time-lab Hi Bob: Just ordered a Sola SOLA 23-23-150-8 CONSTANT VOLTAGE TRANSFORMER 500VAon eBay for under $200 including shipping. -- Have Fun, Brooke

Re: [time-nuts] The home time-lab

/groups/GFS-GPSDOs/info From: Brooke Clarke <bro...@pacific.net> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Friday, July 8, 2016 12:18 PM Subject: Re: [time-nuts] The home time-lab Hi Bob: A re

Re: [time-nuts] The home time-lab

posted.  I certainly got my money's worth! Bob  - AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Tim Shoppa <tsho...@gmail.com> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and

Re: [time-nuts] Good GPSDO on eBay?

And when you build your own, you're still left with the issue of the oscillator.  In my experience, only about 2 out of 3 of the 34310-Ts I get from China are worth using.  If you buy them one at a time your odds aren't good.  OTOH, as your first oscillator, especially for HF use, noise and

[time-nuts] The home time-lab

I hope this isn't too far off topic, as this is having a big impact on my testing. I decided to run an A/B test on one of my GPSDOs: comparing the phase of the two 10MHz output channels.  In the middle of the night, there was a long series of 35ns pops in the phase data.  Strangely enough,

Re: [time-nuts] The home time-lab

a phase variance of only +60ps to -80ps in timelab with an "averaging window" of 0. Bob   --- GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Tim Shoppa <tsho...@gmail.com> To

Re: [time-nuts] The home time-lab

oppa <tsho...@gmail.com> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Thursday, July 7, 2016 8:16 PM Subject: Re: [time-nuts] The home time-lab 1/35ns is about 30MHz. Is there anything in your clock chai

Re: [time-nuts] The home time-lab

  --- GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Hal Murray <hmur...@megapathdsl.net> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo

Re: [time-nuts] The home time-lab

: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Bob Camp <kb...@n1k.org> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Sent: Thursday, July 7, 2016 10:17 PM Subject: Re: [time-nuts] The home time-lab Hi Hav

Re: [time-nuts] The home time-lab

LiFePO battery and float charge the battery with an appropriately constructed linear PS... ALL but the most expensive UPSs use switch-mode power supplies... to power the load when on mains. __ Clay Autery, KY5G MONTAC Enterprises (318) 518-1389 On 7/7/2016 7:44 PM, Bob Stewart

Re: [time-nuts] The home time-lab

list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Hal Murray <hmur...@megapathdsl.net> To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency measurement <time-nuts@febo.com> Cc: Hal Murray <hmur...@megapathdsl.net>; hmur...@megapathdsl.net

[time-nuts] Safely getting the electrical length of a connected antenna feedline

Earlier this year, with some help, I pulled the dish off of an old DishTV antenna on the roof and put a 5V bullet antenna on the mast.  I also pulled a new cable through by attaching it to the old one.  The problem is that I was not able to measure the new cable.  So, the question is, without

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