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

The DC510 and DC5010 phase lock a 320 MHz varicap oscillator to the 1 MHz reference giving them a 3.125ns single shot timing resolution. The DC509, DC5009, DC510, and the DC 5010 are reciprocal counters. The universal timer/counters in the 2236, 2236A, 2247A, and 2252 oscilloscopes phase lock

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

A slight correction to a typo in the description below (sorry for the long delay). The correct Tektronix model numbers of these counters start with DC (not TM). The Tektronix TM500 (manual control) and TM5000 (GPIB or manual control) instruments which used the National Semiconductor MM5837 noise

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

Hello Michael > Thinking out loud, I wonder how bad L1-only, post-processed, would be for > time-nuts use? Especially with a timing-grade antenna (e.g. the common > Trimble Bullet). Dual frequency is great when your receiver has the potential > to move, you have to resolve carrier phase

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

Hi > On Jul 19, 2016, at 7:41 PM, Michael wrote: > > Thanks Tom, Bob, and Mark (wrote my response to Tom first, but didn't hit > send)! > > I've actually been collecting some *ancient* dual-frequency geodetic gear to > play with, some of which have external clock

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

Thanks Tom, Bob, and Mark (wrote my response to Tom first, but didn't hit send)! I've actually been collecting some *ancient* dual-frequency geodetic gear to play with, some of which have external clock inputs (or should be hackable). I've read a lot, but I wasn't sure what people were

[time-nuts] How does sawtooth compensation work?

Navspark has some affordable ($80) modules that do "raw" (carrier phase) output.Also RTK modules for $50 that can give you real-time centimeter accuracy and GPS derived attitude and bearing between two units.Alas, they don't seem to do L1/L2 or accept an external clock. They claim +/-

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

Hi The only way to be sure on either the sawtooth or the cable delay is to try it and see. I have observed it being put in backwards (in both cases) more often than I have seen it put in the right way around. Bob > On Jul 19, 2016, at 12:47 PM, Mark Sims wrote: > >

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

Hi The reason people do not routinely jump to number 3 on the list is cost. The only new GPS modules that I am aware of in category 3 are well over $2K each. That is in comparison to Mark’s favorite $5 modules. You can buy eBay surplus older versions of the fancy boards. So far I have not seen

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

AM Subject: Re: [time-nuts] How does sawtooth compensation work? > Alright, may I vote for tangent #3? I've heard this mentioned in passing > a few times on this list, but never seen it described in detail...so > much so that I have no idea what it means. > > Are we talking an

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

Alright, may I vote for tangent #3? I've heard this mentioned in passing a few times on this list, but never seen it described in detail...so much so that I have no idea what it means. Are we talking an external, steerable LO/clock (similar to #2, except for the location of the oscillator

[time-nuts] How does sawtooth compensation work?

While on the subject of antenna cable delay and sawtooth values, I have only seen Trimble document the sign of the value that you enter to compensate for cable delays (for Trimble devices you enter a negative value). Other receivers may require a positive or negative value. Also, some

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

So now that I’ve said that out loud, I’ve gone back and taken a thousand points from log and plotted them in excel. PastedGraphic-1.pdf Description: Adobe PDF document Looks a *lot* more like sawtooth than noise. Hmm. I might have to reconsider. > On Jul 18, 2016, at 8:06 PM, Nick Sayer

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

ip acts like a -128 ns to +127 ns phase stepper instead of a 0 to 255 ns phase stepper. /tvb - Original Message - From: "Bob Camp" <kb...@n1k.org> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Tuesday, July 19, 20

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

Hi On the sub-set of receivers that send you the sawtooth correction *after* (as in 200 ms after) the PPS …. the delay line correction thing does not work very well. Also in a “strict time nuts” sense, you can only delay the edge. If the sawtooth says the edge was late, you can never get it

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

- Original Message - From: "Tom Van Baak" <t...@leapsecond.com> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Monday, July 18, 2016 9:41 PM Subject: Re: [time-nuts] How does sawtooth compensation work? >>

[time-nuts] How does sawtooth compensation work?

The Tektronix TM509/5009 (and I think the 5010) counter modules have a National Semiconductor noise generator chip in them. It injects noise into the counter to get around counter oscillator/input frequency synchronization. I was once given a TM509 with a bad noise generator chip... Some

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

On Mon, 18 Jul 2016 22:01:01 -0700, you wrote: >> It would be interesting to look at the data to see if you can find the sort > >Hi Hal, > >There's lots of examples of sawtooth patterns at: >http://leapsecond.com/pages/MG1613S/ > >In particular there's this monster:

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

Murray" <hmur...@megapathdsl.net> Sent: Monday, July 18, 2016 9:41 PM Subject: Re: [time-nuts] How does sawtooth compensation work? > > nsa...@kfu.com said: >> Yes, thatâ?Ts true. Given the facilities I have available with the present >> hardware, I donâ?Tt believe I h

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

On Mon, 18 Jul 2016 21:41:51 -0700, you wrote: >> Or use the sawtooth compensation value to control an external variable >> delay line circuit > >Hi Mark, > >Right, one example is https://datasheets.maximintegrated.com/en/ds/DS1020.pdf >or google for silicon delay line. Not sure they're in

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

nsa...@kfu.com said: > Yes, that’s true. Given the facilities I have available with the present > hardware, I don’t believe I have much choice. I am not confident that I > could tell the difference between noise in the phase detection system and > PPS jitter variations that small. If the PA6H

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

Monday, July 18, 2016 8:28 PM Subject: [time-nuts] How does sawtooth compensation work? > Or use the sawtooth compensation value to control an external variable delay > line circuit to move around the PPS signal from the receiver. This can get > interesting to implement if the receiver

[time-nuts] How does sawtooth compensation work?

Or use the sawtooth compensation value to control an external variable delay line circuit to move around the PPS signal from the receiver. This can get interesting to implement if the receiver can output negative values for the sawtooth compensation (hint: add a bias to the sawtooth value to

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

> On Jul 18, 2016, at 3:55 PM, Hal Murray wrote: > >> The systems gravitate towards PLL time constants that average it all away. > > You are overlooking hanging bridges. Yes, that’s true. Given the facilities I have available with the present hardware, I don’t

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

> On Jul 18, 2016, at 4:20 PM, Bob Camp wrote: > > On a receiver with sawtooth correction, you have a manufacturer specific > message that gives > you information on the state of the receiver. It is defined as either > applying to the next pps > or to the pps that just came

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

n because they are a company that makes their own receiver h/w. 3) Carrier phase receivers with external clock input. /tvb - Original Message - From: "Nick Sayer via time-nuts" <time-nuts@febo.com> To: "Chris Arnold via time-nuts" <time-nuts@febo.com> Sent

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

AE6RV.com GFS GPSDO list: groups.yahoo.com/neo/groups/GFS-GPSDOs/info From: Nick Sayer via time-nuts <time-nuts@febo.com> To: Chris Arnold via time-nuts <time-nuts@febo.com> Sent: Monday, July 18, 2016 5:31 PM Subject: [time-nuts] How does sawtooth compensation work? I've

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

Hi The sawtooth process “picks” the closest clock edge and spits out the PPS based on it. If the internal TCXO is off of a point that divides to 1Hz, the edge guess changes fairly often and you can average it out. A drifting TCXO will (effectively) never be at a modulo 1 Hz frequency long

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

> The systems gravitate towards PLL time constants that average it all away. You are overlooking hanging bridges. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to

[time-nuts] How does sawtooth compensation work?

I've read Tom's page about sawtooth PPS jitter and I believe I understand where it comes from.My current GPSDOs ignore the phenomenon. Certainly at the moment, I'm satisfied with that. The systems gravitate towards PLL time constants that average it all away. What I'd like to understand