Re: [time-nuts] Building a GPSDO trouble using Jupiter-T
OK, will check the uBlox datasheet, until now I was assuming that the uBlox series was capable of more than 1 fix per second in navigation and in timing. On Tue, Jan 31, 2012 at 3:17 AM, Didier Juges shali...@gmail.com wrote: You have to spend good money to get a GPS receiver capable of calculating it's time and/or position more than once per second. I am not aware of that being done for timing applications, but it is available for navigation GPS receivers, such as those used to track race cars (for a race car, one second is an eternity). I have seen navigation receivers capable of 10 fixes/second, I am sure there are better ones yet. They cost a lot of money. Didier KO4BB On Mon, Jan 30, 2012 at 4:31 AM, Azelio Boriani azelio.bori...@screen.it wrote: OK, now I know and wonder if other GPS receivers that have frequency outputs behave in this manner. For example the Motorola 100PPS output, the uBlox 800Hz, the Navsync variable frequency output and so on. It is possible to compute solutions from GPS satellite at greater than 1 second rate so the phase of these signals should be adjustable at a rate that could minimize the phase jump... this is only my opinion, not the real possibility. On Mon, Jan 30, 2012 at 11:15 AM, Bruce Griffiths bruce.griffi...@xtra.co.nz wrote: The 10kHz is continuous but its phase jerked on the second. The new phase is held until the next jerk. Bruce Azelio Boriani wrote: Ah, is it a burst of 10KHz once a second? I don't have a Jupiter-T and I'm a PPS-type discplining fan but I thought it was a continuous 10KHz. On Mon, Jan 30, 2012 at 10:33 AM, Attila Kinaliatt...@kinali.ch wrote: On Sun, 29 Jan 2012 00:50:35 -0600 Ray Xurayxu...@gmail.com wrote: For those who have experience using the Jupiter T GPS: I have bought this http://www.ebay.com/itm/**Navman-jupiter-T-Tu60-GPS-Kit-** 1pps-10khz-GPS-Module-/**260790984470 http://www.ebay.com/itm/Navman-jupiter-T-Tu60-GPS-Kit-1pps-10khz-GPS-Module-/260790984470 Ouch... For that price you get already a new LEA-6T, which is a state of the art timing GPS receiver. Beside having the better sensitivity (more satelites in difficult conditions) it features also an frequency output that can go up to 10MHz (or 8MHz if you want low jitter). Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/**mailman/listinfo/time-nuts https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Building a GPSDO trouble using Jupiter-T
On Tue, 31 Jan 2012 10:26:15 +0100 Azelio Boriani azelio.bori...@screen.it wrote: On Tue, Jan 31, 2012 at 3:17 AM, Didier Juges shali...@gmail.com wrote: You have to spend good money to get a GPS receiver capable of calculating it's time and/or position more than once per second. I am not aware of that being done for timing applications, but it is available for navigation GPS receivers, such as those used to track race cars (for a race car, one second is an eternity). I have seen navigation receivers capable of 10 fixes/second, I am sure there are better ones yet. They cost a lot of money. OK, will check the uBlox datasheet, until now I was assuming that the uBlox series was capable of more than 1 fix per second in navigation and in timing. They are. According to the LEA-6T data sheet, the navigation update rates are: LEA-6A: 5Hz LEA-6S: 5Hz LEA-6T: 5Hz LEA-6H: 2Hz LEA-6R: 1Hz Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Racal-Dana 1991 w. Option 4C - what is that ?
Hi Tom I seem to remember seeing a 5MHz standard in a triple oven at PO Research in London were I worked in 1961. The crystal was made there and was a 5MHz 3rd overtone and either a plano-convex or double-convex shape, I believe. They had a lens grinding machine for generating the blanks. This was in the days of the use of natural quartz too. Alan G3NYK - Original Message - From: Tom Van Baak t...@leapsecond.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Tuesday, January 31, 2012 5:41 AM Subject: Re: [time-nuts] Racal-Dana 1991 w. Option 4C - what is that ? What makes 5 MHz more stable than 10 MHz? Why not 2.5 MHz and double twice? Or 1.25 MHz and three doublers? Apparently 2.5 MHz is the most stable of all for reasons not fully understood, but accepted. That's why the early Sulzer oscillators were 2.5 Mc. They doubled them to get 5 MHz. I don't have a reference handy but there are charts and curves in old papers on quartz technology that show a peak in performance (Q?) around 2.5 MHz. Doubling, tripling, or quadupling works too but you get noise at every stage so this is not always a solution. The 2.5 MHz blanks are very large and expensive; I heard that's why the industry moved to 5 and then 10 MHz crystals. Perhaps one of the xtal experts on the list can clarify this for us. See also: Brief History of the Development of Ultra-Precise Oscillators http://www.ieee-uffc.org/main/history.asp?file=norton Fifty Years of Progress in Quartz Crystal Frequency Standards http://www.ieee-uffc.org/main/history.asp?file=frerking /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-5680A decoded - another piece of the puzzle
I did the mod and getting to pin 5 was tough. However Doug mentioned that there is another point to the left of the chip thats easier to get to. Don't recall the point. But if the lead ever comes off of 5 I can assure you I will find it. :-) My unit zeroed about at about 2 V. So I am using a 10 T 10 K bourns pot with 1000 counter. Then a 3.3V reg directly attached with bypass caps driven by 8 V from the regulated supply in the RB. Very clean, 3 leads into the RB. Using shielded cable through the pot hole that actually does nothing. Regards Paul. On Tue, Jan 31, 2012 at 2:19 AM, John Beale be...@bealecorner.com wrote: On 1/29/2012 8:22 PM, Skip Withrow wrote: I recall someone implementing C-field control on a FE-5680A with the pot disabled, but cannot find it now. If someone can point me to that post I sure would appreciate it. I added that post to the FE-5680A FAQ, and added my own photo also to help locate the part. Note, I have not actually tried this modification myself. http://www.ko4bb.com/dokuwiki/**doku.php?id=precision_timing:** fe5680a_faq#adding_an_analog_**adjustment_pothttp://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:fe5680a_faq#adding_an_analog_adjustment_pot Original post was by Bill Riches, Thu, 22 Dec 2011 14:01:18 -0800 __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FE-5680A decoded - another piece of the puzzle
Tue Jan 31 14:15:57 UTC 2012 I did the mod and getting to pin 5 was tough. However Doug mentioned that there is another point to the left of the chip thats easier to get to. Don't recall the point. But if the lead ever comes off of 5 I can assure you I will find it. :-) My unit zeroed about at about 2 V. So I am using a 10 T 10 K bourns pot with 1000 counter. Then a 3.3V reg directly attached with bypass caps driven by 8 V from the regulated supply in the RB. Very clean, 3 leads into the RB. Using shielded cable through the pot hole that actually does nothing. Regards Paul. +++ In case you missed it I had posted the information and a photo of the spot to more easily solder the 100K resistor to give you EFC. I'd go with Bill Riches' suggestion to have the 100K in series with the EFC line. I connected the lead from the 100K to a pin on the DB-9 connector that was freed up when I put the 5V regulator inside so I could run off a single supply. Here's what I did. +++ Sun Jan 15 18:31:39 UTC 2012 I didn't solder the resistor directly to pin 5 of the IC. I found that pin 5 was connected to a nearby SMD capacitor that was a little easier to solder to. Attached is a photo of the correct location if you want to try bringing the EFC out for analog control. http://farm8.staticflickr.com/7170/6702435071_f684967719_b.jpg Mon Jan 16 04:16:53 UTC 2012 I'm not sure what HEX number was loaded into my 5680A but the frequency was just slightly off from 10Mhz. Pin 5 on my 27M4BI quad opamp 'floats at 2.599V and to get 10Mhz out it needs to be at 2.445V. I guess I could correct the frequency digitally so it is at 10Mhz with pin 5 floating but I don't feel it is necessary. The output frequency I measured with zero volts on pin 5 (through the 100K resistor) was 10,000,000.028Hz and with 5V it was pretty close to 9,999,999.969Hz or .031Hz low so it's close to centered. I tried using a 2K 10-turn pot with about 10K on each side to restrict the tuning range further and give me finer control. After the 5680A had been on for a while I tried setting the frequency as close to 10Mhz as I could and watch the drift on my scope using the 10Mhz Rb from my Datum 9390 GPS receiver as the reference. The 5680A seemed to stay within 5ns for 45 minutes so the resolution on the pot is quite good and the 5680A seems quite stable. The pin 5 IC connection is the non-inverting input to the opamp and I'm not sure if connecting the 100K resistor to the inverting input, pin 6, would give you a positive change in frequency for a positive change in voltage or not. If you're using a pot for adjustment or if the controller can be programmed to change the polarity, it doesn't really make any difference and pin 5 works just great. I'm glad Bill Riches found this input and posted the information. -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Mon, 30 Jan 2012 17:47:54 + Mark Sims hol...@hotmail.com wrote: The Tbolt does not have any sawtooth error or corrections. Its' GPS receiver LO is generated from the 10 MHz oscillator. That's what makes it the best GPSDO out there. I just wonder, whether one could take a GPS module, like the LEA-6T and replace the TCXO they have with a VCXO that is phase locked to the 10MHz reference. Or would that cause too much of the hanging bridge problem? Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] OT: Time syncing media in HTML5 - from BBC Research
One of the recurring themes of our work over the past few years has been synchronising web-based media with audio/video. In this first of two technical blog posts on our recent work on P2P Next, we explain why and how we implemented the HTML5 media element attribute startOffsetTime in Firefox to enable accurate synchronisation of out-of-band timestamped metadata with media streamed live to a browser over the internet. Live streams, sub-titles, why NTP can't be used etc. etc. If you are interested, please see: http://www.bbc.co.uk/blogs/researchanddevelopment/2012/01/implementing-startoffsettime-f.shtml Cheers, David -- SatSignal software - quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
What do you think you would gain from that. Does the LEA-6T have a TCXO? Bert In a message dated 1/31/2012 10:53:22 A.M. Eastern Standard Time, att...@kinali.ch writes: On Mon, 30 Jan 2012 17:47:54 + Mark Sims hol...@hotmail.com wrote: The Tbolt does not have any sawtooth error or corrections. Its' GPS receiver LO is generated from the 10 MHz oscillator. That's what makes it the best GPSDO out there. I just wonder, whether one could take a GPS module, like the LEA-6T and replace the TCXO they have with a VCXO that is phase locked to the 10MHz reference. Or would that cause too much of the hanging bridge problem? Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, Jan 31, 2012 at 7:52 AM, Attila Kinali att...@kinali.ch wrote: one could take a GPS module, like the LEA-6T and replace the TCXO they have with a VCXO that is phase locked to the 10MHz reference I'm trying to figure out your goal. The above assumes one already has a 10MHz reference. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, 31 Jan 2012 11:46:45 -0500 (EST) ewkeh...@aol.com wrote: In a message dated 1/31/2012 10:53:22 A.M. Eastern Standard Time, att...@kinali.ch writes: I just wonder, whether one could take a GPS module, like the LEA-6T and replace the TCXO they have with a VCXO that is phase locked to the 10MHz reference. Or would that cause too much of the hanging bridge problem? What do you think you would gain from that. Does the LEA-6T have a TCXO? Bert Yes, the LEA-*T's have a TCXO. I'd expect less jitter in the 1PPS if the oscillator is more stable. A TCXO has usually something in the range of 10-100ppb/°C temperature coefficients, while from a OCXO you can expect 10ppb over its whole temperature range (usually somewhere from 0 to 50°C), ie getting a temperature coefficient that is in the range of 10 to 100 times better. Attila Kinali -- Why does it take years to find the answers to the questions one should have asked long ago? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, 31 Jan 2012 09:32:22 -0800 Chris Albertson albertson.ch...@gmail.com wrote: On Tue, Jan 31, 2012 at 7:52 AM, Attila Kinali att...@kinali.ch wrote: one could take a GPS module, like the LEA-6T and replace the TCXO they have with a VCXO that is phase locked to the 10MHz reference I'm trying to figure out your goal. The above assumes one already has a 10MHz reference. Let's say, i'm building a GPSDO with a high quality OCXO. Wouldnt it then make sense to lock the reference clock of the GPS receiver also to that OCXO? Attila Kinali -- Why does it take years to find the answers to the questions one should have asked long ago? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, 31 Jan 2012 09:32:22 -0800 Chris Albertson albertson.ch...@gmail.com wrote: On Tue, Jan 31, 2012 at 7:52 AM, Attila Kinali att...@kinali.ch wrote: one could take a GPS module, like the LEA-6T and replace the TCXO they have with a VCXO that is phase locked to the 10MHz reference I'm trying to figure out your goal. The above assumes one already has a 10MHz reference. Let's say, i'm building a GPSDO with a high quality OCXO. Wouldnt it then make sense to lock the reference clock of the GPS receiver also to that OCXO? Attila Kinali Exactly that _is_ the appeal of the Tbolts. What frequency does the uBlox 6T TCXO have? Let us know your progress. -- Björn ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-5680A decoded - another piece of the puzzle
Thanks Arthur. Thats the thread I was referring to. On Tue, Jan 31, 2012 at 10:25 AM, Arthur Dent golgarfrinc...@yahoo.comwrote: Tue Jan 31 14:15:57 UTC 2012 I did the mod and getting to pin 5 was tough. However Doug mentioned that there is another point to the left of the chip thats easier to get to. Don't recall the point. But if the lead ever comes off of 5 I can assure you I will find it. :-) My unit zeroed about at about 2 V. So I am using a 10 T 10 K bourns pot with 1000 counter. Then a 3.3V reg directly attached with bypass caps driven by 8 V from the regulated supply in the RB. Very clean, 3 leads into the RB. Using shielded cable through the pot hole that actually does nothing. Regards Paul. +++ In case you missed it I had posted the information and a photo of the spot to more easily solder the 100K resistor to give you EFC. I'd go with Bill Riches' suggestion to have the 100K in series with the EFC line. I connected the lead from the 100K to a pin on the DB-9 connector that was freed up when I put the 5V regulator inside so I could run off a single supply. Here's what I did. +++ Sun Jan 15 18:31:39 UTC 2012 I didn't solder the resistor directly to pin 5 of the IC. I found that pin 5 was connected to a nearby SMD capacitor that was a little easier to solder to. Attached is a photo of the correct location if you want to try bringing the EFC out for analog control. http://farm8.staticflickr.com/7170/6702435071_f684967719_b.jpg Mon Jan 16 04:16:53 UTC 2012 I'm not sure what HEX number was loaded into my 5680A but the frequency was just slightly off from 10Mhz. Pin 5 on my 27M4BI quad opamp 'floats at 2.599V and to get 10Mhz out it needs to be at 2.445V. I guess I could correct the frequency digitally so it is at 10Mhz with pin 5 floating but I don't feel it is necessary. The output frequency I measured with zero volts on pin 5 (through the 100K resistor) was 10,000,000.028Hz and with 5V it was pretty close to 9,999,999.969Hz or .031Hz low so it's close to centered. I tried using a 2K 10-turn pot with about 10K on each side to restrict the tuning range further and give me finer control. After the 5680A had been on for a while I tried setting the frequency as close to 10Mhz as I could and watch the drift on my scope using the 10Mhz Rb from my Datum 9390 GPS receiver as the reference. The 5680A seemed to stay within 5ns for 45 minutes so the resolution on the pot is quite good and the 5680A seems quite stable. The pin 5 IC connection is the non-inverting input to the opamp and I'm not sure if connecting the 100K resistor to the inverting input, pin 6, would give you a positive change in frequency for a positive change in voltage or not. If you're using a pot for adjustment or if the controller can be programmed to change the polarity, it doesn't really make any difference and pin 5 works just great. I'm glad Bill Riches found this input and posted the information. -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] FE-5680A internal connector
Hi, Has anybody investigated the internal connector at the end of the board? It seems that it is only for factory tests/adjustments, but probably there are interesting signals there. I will probe there but I promised myself not power the unit again until I have a proper setup (and after replacing the blown 74ACT240). Ignacio, EB4APL ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, 31 Jan 2012 18:50:08 +0100 b...@lysator.liu.se wrote: Let's say, i'm building a GPSDO with a high quality OCXO. Wouldnt it then make sense to lock the reference clock of the GPS receiver also to that OCXO? Attila Kinali Exactly that _is_ the appeal of the Tbolts. Yes, but can this be replicated with a standard GPS module? And does it have side effects? What frequency does the uBlox 6T TCXO have? 48MHz as stated in the Timing AppNote. Let us know your progress. My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? The alternative would be to use an FPGA, but i'm reluctant to do that as it makes the whole system a lot more complex. Attila Kinali -- Why does it take years to find the answers to the questions one should have asked long ago? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Building a GPSDO trouble using Jupiter-T
On 31/01/12 03:17, Didier Juges wrote: You have to spend good money to get a GPS receiver capable of calculating it's time and/or position more than once per second. I am not aware of that being done for timing applications, but it is available for navigation GPS receivers, such as those used to track race cars (for a race car, one second is an eternity). I have seen navigation receivers capable of 10 fixes/second, I am sure there are better ones yet. They cost a lot of money. I have receivers which can run navigation solutions up to 10 times per second and raw-data results up to 50 times per second, I just don't have that neat options in it. Ah well. Double-frequency never the less. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Quick tutorial on jitter
On Mon, Jan 30, 2012 at 11:46 PM, Magnus Danielson mag...@rubidium.dyndns.org wrote: So jitter can be many things and many values, all depending on what you do. Indeed. Here's a mostly-from-textbooks view we use often for synchronization systems in particle accelerators: http://dl.dropbox.com/u/13409775/timing.pdf Cheers, Javier ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
El 31/01/2012 20:43, Attila Kinali escribió: My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? You can have a look on these http://www.ti.com/mcu/docs/mculuminaryfamilynode.tsp?sectionId=95tabId=2597familyId=1756 Some of them have IEEE-1588, like the LM3S9B96 Regards, Javier ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, 31 Jan 2012 20:43:35 +0100, Attila Kinali wrote: My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? Some of the ST's supports IEEE-1588 http://www.embeddedstar.com/weblog/2011/09/21/stm32-f4-mcu/ www.mouser.com/pdfdocs/BRSTM32F4_v7final.pdf I'd suggest a $20 STM32-F4-Discovery (Digikey etc) http://parts.digikey.com/1/parts/2484058-eval-kit-stm32f-discovery- stm32f4discovery.html And a Phy (The mac is in the F4) $10 http://www.ebay.de/itm/DP83848-Ethernet-Physical-Transceiver-RJ45- connector-control-interface-Board-Kit-/260868624339 Some www-sw is here (German use google translate) http://www.mikrocontroller.net/topic/237223#2491080 The F4 even supports Single precision Floats in HW , and has both ADC DAC (with the ADC/DAC vref pin on external pin). 1G flash , 192k Ram , and it runs 168Mhz. I think there is 2 x 32bit timers (Fclock/2) , and a fair amount of 16bit timers. It comes with build in debugger (proprietarary) , but the debug protocol has been reversed ... (see texane project) , and afaik it is now suported in openocd. So arm-gcc arm-gdb can be used (ie codesourcery). ST suggests Atollic as gcc toolchain , but that's imho handicapped in the free version. I have earlier suggested the F4-Discovery , as a Tnut GPSDO/OCXO/RBXO controller board. CFO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Prologix GPIB-ETH - Linux examples ?
On Mon, 30 Jan 2012 19:23:10 +, cfo wrote: I just got my Prologix GPIB-ETH I am 90% Linux Ubuntu based , and would like to get 99% based. So i am looking for some C code examples, implementing the linux networking part. Thanx for all the suggestions , i'll have a look at porting winsock apps to sockets. But i really like PHK's pylt , and will prob. give a prologic-eth driver a try. I have never tried python , but i hope i can ask for help on the net. After all i do have PHK's USB py driver as a nice skeleton. CFO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, 31 Jan 2012 21:06:04 +0100 Javier Herrero jherr...@hvsistemas.es wrote: El 31/01/2012 20:43, Attila Kinali escribió: My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? You can have a look on these http://www.ti.com/mcu/docs/mculuminaryfamilynode.tsp?sectionId=95tabId=2597familyId=1756 Some of them have IEEE-1588, like the LM3S9B96 This was exactly the device i intended to use. But it doesnt really have 32bit timers. They cascade two 16bit timers to get 32bit, but then all kind of restrictions apply which make the timers unusable. And when using 16bit timers, i'll get an overflow every 800us (at 80MHz clock). I browsed trough the internets and could find the following devices: LPC18xx (NXP): Look nice, but still in development or early production. I especially like that they (will be) are available in a 200 pin QFP. This would enable to use all the functions of the chip while still being able to solder one by hand. K60 (Freescale): Hell of a confusing documentation. Also quite new. Have only 16bit timers. A big issue is that they have a crypto unit on chip, which makes them export restricted. Ie the only way to buy them is from a local distributor which makes them expensive. STM32-F2/F4 (ST): ST doesn't want to give me the documentation to those. (website fails w/o error message) I havent found any other chips yet. Sofar the options i see are: * wait for the LPC18xx become available in quanities (can take a year) * Use a LM3S9B96 together with a small FPGA to implement the counter functions. Any hints appreciated Attila Kinali -- Why does it take years to find the answers to the questions one should have asked long ago? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
If you are willing to use external counters: Dallas DS2423 Dual 32-bit Counter Or, if you have an unlimited budget: http://www.cwcelectronicsystems.com/dual32ct_modulario.html the word defense is prominent here :-). Or counter products from: http://www.lsicsi.com/ I use encoder interfaces from the last company and recommend them! Don Attila Kinali On Tue, 31 Jan 2012 21:06:04 +0100 Javier Herrero jherr...@hvsistemas.es wrote: El 31/01/2012 20:43, Attila Kinali escribió: My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? You can have a look on these http://www.ti.com/mcu/docs/mculuminaryfamilynode.tsp?sectionId=95tabId=2597familyId=1756 Some of them have IEEE-1588, like the LM3S9B96 This was exactly the device i intended to use. But it doesnt really have 32bit timers. They cascade two 16bit timers to get 32bit, but then all kind of restrictions apply which make the timers unusable. And when using 16bit timers, i'll get an overflow every 800us (at 80MHz clock). I browsed trough the internets and could find the following devices: LPC18xx (NXP): Look nice, but still in development or early production. I especially like that they (will be) are available in a 200 pin QFP. This would enable to use all the functions of the chip while still being able to solder one by hand. K60 (Freescale): Hell of a confusing documentation. Also quite new. Have only 16bit timers. A big issue is that they have a crypto unit on chip, which makes them export restricted. Ie the only way to buy them is from a local distributor which makes them expensive. STM32-F2/F4 (ST): ST doesn't want to give me the documentation to those. (website fails w/o error message) I havent found any other chips yet. Sofar the options i see are: * wait for the LPC18xx become available in quanities (can take a year) * Use a LM3S9B96 together with a small FPGA to implement the counter functions. Any hints appreciated Attila Kinali -- Why does it take years to find the answers to the questions one should have asked long ago? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
In message deac00aacc21732c4705e34cd4097d7a.squir...@www.webmail.montana.com, Don Latham writes: want. Can anyone recommend a uC with 32bit timers and IEEE 1588 An suitable motherboard and an intel 82599 based ethernet card ? The latter will set you back approx $700, but $1000 should get you far in total. The 82599 has some very interesting time-nuts features with respect to the GPIO pins. Unfortunately I have not been able to find out if these pins are accessible on the Intel ethernet cards. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
If anyone is interested, I have just got hold of a PDF of the Technical Manual TM 5680-0211 for 5680A series Rubidiums. Please contact me off list for a copy (1M, so too large to post on time-nuts@febo.com) Rob Kimberley -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Attila Kinali Sent: 31 January 2012 20:47 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-.5680A trimming resolution On Tue, 31 Jan 2012 21:06:04 +0100 Javier Herrero jherr...@hvsistemas.es wrote: El 31/01/2012 20:43, Attila Kinali escribi : My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? You can have a look on these http://www.ti.com/mcu/docs/mculuminaryfamilynode.tsp?sectionId=95tabI d=2597familyId=1756 Some of them have IEEE-1588, like the LM3S9B96 This was exactly the device i intended to use. But it doesnt really have 32bit timers. They cascade two 16bit timers to get 32bit, but then all kind of restrictions apply which make the timers unusable. And when using 16bit timers, i'll get an overflow every 800us (at 80MHz clock). I browsed trough the internets and could find the following devices: LPC18xx (NXP): Look nice, but still in development or early production. I especially like that they (will be) are available in a 200 pin QFP. This would enable to use all the functions of the chip while still being able to solder one by hand. K60 (Freescale): Hell of a confusing documentation. Also quite new. Have only 16bit timers. A big issue is that they have a crypto unit on chip, which makes them export restricted. Ie the only way to buy them is from a local distributor which makes them expensive. STM32-F2/F4 (ST): ST doesn't want to give me the documentation to those. (website fails w/o error message) I havent found any other chips yet. Sofar the options i see are: * wait for the LPC18xx become available in quanities (can take a year) * Use a LM3S9B96 together with a small FPGA to implement the counter functions. Any hints appreciated Attila Kinali -- Why does it take years to find the answers to the questions one should have asked long ago? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
El 31/01/2012 21:47, Attila Kinali escribió: This was exactly the device i intended to use. But it doesnt really have 32bit timers. They cascade two 16bit timers to get 32bit, but then all kind of restrictions apply which make the timers unusable. And when using 16bit timers, i'll get an overflow every 800us (at 80MHz clock). I see... for edge count and edge time, only individual timers and not concatenates. I've had a look to the LM3S9D96, and it is more or less the same (the exception is that it is marketed as 4 32-bit timers that can be used as 8 16-bit timers :) ), and I suspect that all the family will have similar behaviout. A pity... since for Ethernet it includes the LAN and PHY on-chip. Regards, Javier ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, 31 Jan 2012 21:47:15 +0100, Attila Kinali wrote: STM32-F2/F4 (ST): ST doesn't want to give me the documentation to those. (website fails w/o error message) I have no probs with the ST site (Discovery-F4) http://www.st.com/internet/evalboard/product/252419.jsp You want these for the MCU http://www.st.com/internet/mcu/product/252140.jsp DataSheet http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/ DATASHEET/DM00037051.pdf Errata http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/ ERRATA_SHEET/DM00037591.pdf Reference Manual http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/ REFERENCE_MANUAL/DM00031020.pdf CFO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
The Navsync FTS125 is an example where the GPS receiver engine (the CW25) is driven by a 20MHz fixed OCXO. At the moment I don't know if the CW25 of the FTS125 has a specific firmware for that but I suspect that it must be so. In my opinion it is best to have a tunable OCXO (like the TBolt) to have the best performance. On Tue, Jan 31, 2012 at 10:19 PM, cfo xne...@luna.kyed.com wrote: On Tue, 31 Jan 2012 21:47:15 +0100, Attila Kinali wrote: STM32-F2/F4 (ST): ST doesn't want to give me the documentation to those. (website fails w/o error message) I have no probs with the ST site (Discovery-F4) http://www.st.com/internet/evalboard/product/252419.jsp You want these for the MCU http://www.st.com/internet/mcu/product/252140.jsp DataSheet http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/ DATASHEET/DM00037051.pdf Errata http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/ ERRATA_SHEET/DM00037591.pdf Reference Manual http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/ REFERENCE_MANUAL/DM00031020.pdf CFO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Racal-Dana 1991 w. Option 4C - what is that ?
It's a 5Mhz crystal with a frequency doubler at the output. Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of cfo Sent: 30 January 2012 17:25 To: time-nuts@febo.com Subject: Re: [time-nuts] Racal-Dana 1991 w. Option 4C - what is that ? On Fri, 20 Jan 2012 09:18:32 -0800, Larry McDavid wrote: I have been looking for a Racal 9462 ocxo , for my Racal-Dana 1991 counter. I will prob. use my Tbolt anyway , and save the money. But i'm confused ... Is it a 5 Mhz or a 10 Mhz unit. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
Does anyone else have problems with links to tf.nist.gov? When I try to get the pdf's, I get no reply from the url at all. My browser puts out the request, but gets no reply whatsoever and eventually gives up. This also happened previously with this url http://tf.boulder.nist.gov/general/pdf/2556.pdf I even tried turning my entire firewall off, but there is no reply coming back to allow through. Any ideas anyone? Or could someone temporarily put the .pdf's on a server somewhere so I can download them? On 2012-01-31 16:24, Tom Van Baak wrote: You may find these two papers helpful: Introduction to time and frequency metrology http://tf.nist.gov/general/pdf/1288.pdf Fundamentals of Time and Frequency http://tf.nist.gov/general/pdf/1498.pdf /tvb -- Cheers, Ken vk7...@users.tasmanet.com.au www.vk7krj.com 'It seems hard to sneak a look at God's cards. But that He plays dice and uses telepathic methods is something that I cannot believe for a single moment.' (Einstein's famous quote on Quantum theory) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, Jan 31, 2012 at 9:40 AM, Attila Kinali att...@kinali.ch wrote: Let's say, i'm building a GPSDO with a high quality OCXO. Wouldnt it then make sense to lock the reference clock of the GPS receiver also to that OCXO? Yes, I see. That is exactly what Trimble does in the Thunderbolt. There is only one OCXO in the T-bolt that is used for both the output 10MHz and to run the receiver. That system works well for them Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
Ken, The links are working fine for me on our home network and our firewall is set to medium/high security mode. Are you having the same issues with any other .gov links? Steve On Jan 31, 2012, at 5:09 PM, ken johnson bats...@gmail.com wrote: Does anyone else have problems with links to tf.nist.gov? When I try to get the pdf's, I get no reply from the url at all. My browser puts out the request, but gets no reply whatsoever and eventually gives up. This also happened previously with this url http://tf.boulder.nist.gov/general/pdf/2556.pdf I even tried turning my entire firewall off, but there is no reply coming back to allow through. Any ideas anyone? Or could someone temporarily put the .pdf's on a server somewhere so I can download them? On 2012-01-31 16:24, Tom Van Baak wrote: You may find these two papers helpful: Introduction to time and frequency metrology http://tf.nist.gov/general/pdf/1288.pdf Fundamentals of Time and Frequency http://tf.nist.gov/general/pdf/1498.pdf /tvb -- Cheers, Ken vk7...@users.tasmanet.com.au www.vk7krj.com 'It seems hard to sneak a look at God's cards. But that He plays dice and uses telepathic methods is something that I cannot believe for a single moment.' (Einstein's famous quote on Quantum theory) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On Tue, Jan 31, 2012 at 11:43 AM, Attila Kinali att...@kinali.ch wrote: My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? Does the system need to be small? If not Generic PC hardware can work. Buy an Intel Atom main board. For under $85 you get a soldered down CPU and all the normal PC stuff, PCI bus and all. The board I bought does not have a CPU fan and burns all of about 5 watts. Or you can re-cycle and old notebook computer. If you run Linux then yes it supports IEEE 1588. There are real-time versions of linux that give you easy access to low level hardware much like with a uP. If you were going to mass produce these you could cut costs but for a one-off using a $100 PC is reasonable. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Android App for UTC vs GPS vs TAI vs Device Time
Hi Folks, We all know the issue of Android Devices that report GPS as UTC Time, and all that goes with it. I do have TAI Clock installed, along with UTC Clock and Navy Clock Now.. Even though I have a Samsung S-2, what I'm really after is an app that shows the following: 1) Local Device Time 2) UTC Time (maybe grabbed from a remote NTP Server) 3) GPS Time (derived from the GPS constellation, but not making system time negative 15 seconds 4) TAI Time (derived from 1,2, or 3 above..) I have apps for some combination of the above, but not all. Anyone know of such an animal ? At least one of the apps seems to say my device is syunc with GPS, when others suggest it is syncronised with UTC! [This is also to explain and demonstrate the differences to a friend, but it would be good to be able to tell what time-frame the S-2 is working to...] Best Regards Iain ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
Thanks for the reply Steve- yes, I can access nasa.gov and nist.gov ok, but no matter which way I try, tf.nist.gov just will not reply to my browser's request. It's not as if my firewall is stopping the reply, there is simply no reply coming back. The url resolves to 132.163.4.169, and a whois shows it as tf.nist.gov, so there is no problem with the dns lookup. I did a whois on my own public ip and it comes up ok as australian registered so there shouldn't be any problem with it being blocked by nist I would have thought. It is a puzzle- I really would like to have a read of these documents! On Wed, Feb 1, 2012 at 10:27 AM, Steve steve-kr...@cox.net wrote: Ken, The links are working fine for me on our home network and our firewall is set to medium/high security mode. Are you having the same issues with any other .gov links? Steve -- Cheers, Ken vk7...@users.tasmanet.com.au www.vk7krj.com 'It seems hard to sneak a look at God's cards. But that He plays dice and uses telepathic methods is something that I cannot believe for a single moment.' (Einstein's famous quote on Quantum theory) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
Ken, I sent you an email with all three documents attached. Did you not receive them? .73, Brent, KD0GLS, Minneapolis On 31 Jan 2012, at 18:03, ken johnson wrote: Thanks for the reply Steve- yes, I can access nasa.gov and nist.gov ok, but no matter which way I try, tf.nist.gov just will not reply to my browser's request. It's not as if my firewall is stopping the reply, there is simply no reply coming back. The url resolves to 132.163.4.169, and a whois shows it as tf.nist.gov, so there is no problem with the dns lookup. I did a whois on my own public ip and it comes up ok as australian registered so there shouldn't be any problem with it being blocked by nist I would have thought. It is a puzzle- I really would like to have a read of these documents! On Wed, Feb 1, 2012 at 10:27 AM, Steve steve-kr...@cox.net wrote: Ken, The links are working fine for me on our home network and our firewall is set to medium/high security mode. Are you having the same issues with any other .gov links? Steve -- Cheers, Ken vk7...@users.tasmanet.com.au www.vk7krj.com 'It seems hard to sneak a look at God's cards. But that He plays dice and uses telepathic methods is something that I cannot believe for a single moment.' (Einstein's famous quote on Quantum theory) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
On Tue, Jan 31, 2012 at 4:02 PM, ken johnson bats...@gmail.com wrote: Thanks for the reply Steve- yes, I can access nasa.gov and nist.gov ok, but no matter which way I try, tf.nist.gov just will not reply to my browser's request. It's not as if my firewall is stopping the reply, It's their firewall. What happens is they get some kind of denial of service attack from say China so they block huge segments of IP address space. Admins either over react or don't know how else to do it. maybe try using a US based Web Proxy. Google will find one. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] OT: Time syncing media in HTML5 - from BBC Research
On 31/01/12 17:00, David J Taylor wrote: One of the recurring themes of our work over the past few years has been synchronising web-based media with audio/video. In this first of two technical blog posts on our recent work on P2P Next, we explain why and how we implemented the HTML5 media element attribute startOffsetTime in Firefox to enable accurate synchronisation of out-of-band timestamped metadata with media streamed live to a browser over the internet. Live streams, sub-titles, why NTP can't be used etc. etc. If you are interested, please see: http://www.bbc.co.uk/blogs/researchanddevelopment/2012/01/implementing-startoffsettime-f.shtml This is really a side-track to the normal time-nuts issues, but it is interesting to note that there are several formats for audio and video, lacking the key aspect of time coordination between the signals even if they is brought in the same transport stream. A bit annoying. The development now allows us even more ways to loose lip sync than ever before. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
Rob, I would be happy to put it on one of my web pages so people could download it. On Wed, Feb 1, 2012 at 8:14 AM, Rob Kimberley robkimber...@btinternet.comwrote: If anyone is interested, I have just got hold of a PDF of the Technical Manual TM 5680-0211 for 5680A series Rubidiums. Please contact me off list for a copy (1M, so too large to post on time-nuts@febo.com) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
On 31/01/12 07:27, Javier Herrero wrote: El 31/01/2012 02:52, Magnus Danielson escribió: On 31/01/12 02:20, Bob Camp wrote: Hi Simple answer is don't bother. More complex answer - of course you can. You will get a forest of spikes (every 5, MHz or so ). Also, since the 5,3 MHz is modulated, 1,4 kHz apart is the two signals, and then a skirt of side-bands as the frequency modulation is relatively quick. It's not clean. BTW. A fun hack would be to hook up the 63,8976 MHz OCXO in replacement of the 60 MHz and then re-adjusting the DDS to 2.35645 MHz, as the 107s overtone of the OCXO minus the new DDS frequency hits the Rb resonance. Cheers, Magnus And then we will have a not less fun 10.6469MHz and 0.939Hz outputs :) However, if the DDS can easily be reprogrammed to large offsets (and the output filter is a simple lowpass...), that idea is very useful if you need an strange frequency and have an OCXO at 6x that extrange frequency ;) We seems to get those OCXOs alongside anyway, so I was just toying with the idea to see what kind of performance that would give us. A quieter OCXO. For more ordinary frequency output, an additional DDS like the original 5680 would be nice. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
Let's say, i'm building a GPSDO with a high quality OCXO. Wouldnt it then make sense to lock the reference clock of the GPS receiver also to that OCXO? Attila Kinali It's a design decision. Most GPSDO sold are made by companies that buy an OEM GPS timing receiver and then create a GPSDO with the usual assortment of OCXO, TIC, computer and DAC. The exception would be if you are a GPS company and can integrate the components, as Trimble did with the Thunderbolt. But most companies selling GPSDO, and all amateurs building homebrew GPSDO, have to use the separate component method. Note the really high-end GPS timing receivers use an external reference clock and don't even bother to lock it. The advantage with this is 1) you don't need the DAC (which just adds noise), 2) you can use good clocks like cesium or masers which don't have EFC, and 3) you collect the phase error information for post-processing -- which is much more accurate than trying to steer an oscillator in real time. And also, 4) you can run multiple receivers off the same clock if necessary. We're waiting for some brave soul to implement an SDR-based GPS timing receiver; we can all then experiment with the TBolt model instead of the TIC/DAC model of GPSDO. /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
Hi Brent, yes I did thanks, but due to the slightly complicated way I have to use to receive mail from the lists I am on, I replied to Steve's email before I saw yours. Your efforts are are appreciated, I am going to enjoy reading the files. On Wed, Feb 1, 2012 at 11:07 AM, KD0GLS kd0...@mninter.net wrote: Ken, I sent you an email with all three documents attached. Did you not receive them? .73, Brent, KD0GLS, Minneapolis ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Racal-Dana 1991 w. Option 4C - what is that ?
Hi It's not all smoke and mirrors. The Q of quartz goes up as frequency goes down. Nobody really debates that. As frequency goes down blank diameter would need to grow to keep everything same / same. Again not much debate. What does get a lot of debate is just how small you can get blank diameter and still get reasonable performance. If people just liked 3 diameter crystal packages. Bob On Jan 31, 2012, at 12:41 AM, Tom Van Baak t...@leapsecond.com wrote: What makes 5 MHz more stable than 10 MHz? Why not 2.5 MHz and double twice? Or 1.25 MHz and three doublers? Apparently 2.5 MHz is the most stable of all for reasons not fully understood, but accepted. That's why the early Sulzer oscillators were 2.5 Mc. They doubled them to get 5 MHz. I don't have a reference handy but there are charts and curves in old papers on quartz technology that show a peak in performance (Q?) around 2.5 MHz. Doubling, tripling, or quadupling works too but you get noise at every stage so this is not always a solution. The 2.5 MHz blanks are very large and expensive; I heard that's why the industry moved to 5 and then 10 MHz crystals. Perhaps one of the xtal experts on the list can clarify this for us. See also: Brief History of the Development of Ultra-Precise Oscillators http://www.ieee-uffc.org/main/history.asp?file=norton Fifty Years of Progress in Quartz Crystal Frequency Standards http://www.ieee-uffc.org/main/history.asp?file=frerking /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Building a GPSDO trouble using Jupiter-T
On Mon, Jan 30, 2012 at 6:17 PM, Didier Juges shali...@gmail.com wrote: You have to spend good money to get a GPS receiver capable of calculating it's time and/or position more than once per second. I am not aware of that being done for timing applications, but it is available for navigation GPS receivers, such as those used to track race cars (for a race car, one second is an eternity). I have seen navigation receivers capable of 10 fixes/second, I am sure there are better ones yet. They cost a lot of money. I'm pretty sure those GPS recievers that send out more frequent data, at say 2Hz or 5Hz are just interpolating. It is not more accurate. The GPS sats only send a frame once over 6 seconds. They send at higher rate so that the system using the GPS does not need to know how to dead reckon and can have decent results for simply using last reported position Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Building a GPSDO trouble using Jupiter-T
On 01/02/12 01:29, Chris Albertson wrote: On Mon, Jan 30, 2012 at 6:17 PM, Didier Jugesshali...@gmail.com wrote: You have to spend good money to get a GPS receiver capable of calculating it's time and/or position more than once per second. I am not aware of that being done for timing applications, but it is available for navigation GPS receivers, such as those used to track race cars (for a race car, one second is an eternity). I have seen navigation receivers capable of 10 fixes/second, I am sure there are better ones yet. They cost a lot of money. I'm pretty sure those GPS recievers that send out more frequent data, at say 2Hz or 5Hz are just interpolating. It is not more accurate. The GPS sats only send a frame once over 6 seconds. They send at higher rate so that the system using the GPS does not need to know how to dead reckon and can have decent results for simply using last reported position The frames does not relate to the rate of raw-data or solutions. You could track every 1 ms, as it would align with the rate of a full C/A code cycle. Typically these are integrated into complete sub-code symbols, of 20 ms or 50 bauds, so it is not unfair to see that rate of raw-data. The solution can be run as often if CPU time for all the calculations are there. The ephemeris data is designed such that it doesn't need to change often and is re-transmitted regularly, so those bits isn't immediately used for navigation solution by necessity. Their phase is however important. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
We're waiting for some brave soul to implement an SDR-based GPS timing receiver; we can all then experiment with the TBolt model instead of the TIC/DAC model of GPSDO. There are several projects that do this. There is one written using GNU Radio. I forget the details but I saw it years ago. http://www.kamieniecki.com/krys/gps proof of concept only, not finished http://gps.psas.pdx.edu/ Not really SDR but ... firmware that is meant to run on the receiver board itself, giving you direct access to the GPS chipset. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On 31/01/12 20:43, Attila Kinali wrote: On Tue, 31 Jan 2012 18:50:08 +0100 b...@lysator.liu.se wrote: Let's say, i'm building a GPSDO with a high quality OCXO. Wouldnt it then make sense to lock the reference clock of the GPS receiver also to that OCXO? Attila Kinali Exactly that _is_ the appeal of the Tbolts. Yes, but can this be replicated with a standard GPS module? Yes. If you look up old papers, they already did this with Oncores, Cesium clocks and synthesis. And does it have side effects? If you've done it right, it lowers the receivers noise. The position becomes less shaken by the jerk effect of the oscillator noise, while frequency and drift also affects the solution to some degree. This side-effect is covered in literature if you look for it. What frequency does the uBlox 6T TCXO have? 48MHz as stated in the Timing AppNote. Produceable. Let us know your progress. My current progress is that the uC i wanted to use does not do what i want. Can anyone recommend a uC with 32bit timers and IEEE 1588 support? The alternative would be to use an FPGA, but i'm reluctant to do that as it makes the whole system a lot more complex No pain, no gain? Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] FE-.5680A trimming resolution
On 31/01/12 22:14, Rob Kimberley wrote: If anyone is interested, I have just got hold of a PDF of the Technical Manual TM 5680-0211 for 5680A series Rubidiums. Please contact me off list for a copy (1M, so too large to post on time-nuts@febo.com) I'll have it. The russian version is here: http://morion.com.ru/uploaded/FE-5680_manual_rus.pdf Browing through it, it becomes obvious that this describes the new 5680As that we got, with 60 MHz clock and all. Steering resolution is also as Javierr reversed out. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] TM 5680-0211 for 5680A series Rubidiums
On 31/01/12 22:14, Rob Kimberley wrote: If anyone is interested, I have just got hold of a PDF of the Technical Manual TM 5680-0211 for 5680A series Rubidiums. Please contact me off list for a copy (1M, so too large to post on time-nuts@febo.com) I'd ask off line but the quotes did not preserve your email address. Would you send a copy to me at albertson.ch...@gmail.com If you like, I can put this some place where others can get get directly Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] TM 5680-0211 for 5680A series Rubidiums
Same here, rayxu...@gmail.com Thank you Ray Xu On Tue, Jan 31, 2012 at 7:59 PM, Chris Albertson albertson.ch...@gmail.comwrote: On 31/01/12 22:14, Rob Kimberley wrote: If anyone is interested, I have just got hold of a PDF of the Technical Manual TM 5680-0211 for 5680A series Rubidiums. Please contact me off list for a copy (1M, so too large to post on time-nuts@febo.com) I'd ask off line but the quotes did not preserve your email address. Would you send a copy to me at albertson.ch...@gmail.com If you like, I can put this some place where others can get get directly Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- __ 73, Ray Xu KF5LJO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] TM 5680-0211 for 5680A series Rubidiums
Stranger still. I never received the first email and am interested. Regards Paul. On Tue, Jan 31, 2012 at 9:15 PM, Ray Xu rayxu...@gmail.com wrote: Same here, rayxu...@gmail.com Thank you Ray Xu On Tue, Jan 31, 2012 at 7:59 PM, Chris Albertson albertson.ch...@gmail.comwrote: On 31/01/12 22:14, Rob Kimberley wrote: If anyone is interested, I have just got hold of a PDF of the Technical Manual TM 5680-0211 for 5680A series Rubidiums. Please contact me off list for a copy (1M, so too large to post on time-nuts@febo.com) I'd ask off line but the quotes did not preserve your email address. Would you send a copy to me at albertson.ch...@gmail.com If you like, I can put this some place where others can get get directly Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- __ 73, Ray Xu KF5LJO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] TM 5680-0211 for 5680A series Rubidiums
In the interim, here is a translation of the Russian manual. http://translate.google.com/translate?hl=ensl=ruu=http://morion.com.ru/uploaded/FE-5680_manual_rus.pdf Sam. - Original Message - From: paul swed [mailto:paulsw...@gmail.com] To: Discussion of precise time and frequency measurement [mailto:time-nuts@febo.com] Sent: Wed, 01 Feb 2012 13:29:48 +1100 Subject: Re: [time-nuts] TM 5680-0211 for 5680A series Rubidiums Stranger still. I never received the first email and am interested. Regards Paul. On Tue, Jan 31, 2012 at 9:15 PM, Ray Xu rayxu...@gmail.com wrote: Same here, rayxu...@gmail.com Thank you Ray Xu On Tue, Jan 31, 2012 at 7:59 PM, Chris Albertson albertson.ch...@gmail.comwrote: On 31/01/12 22:14, Rob Kimberley wrote: If anyone is interested, I have just got hold of a PDF of the Technical Manual TM 5680-0211 for 5680A series Rubidiums. Please contact me off list for a copy (1M, so too large to post on time-nuts@febo.com) I'd ask off line but the quotes did not preserve your email address. Would you send a copy to me at albertson.ch...@gmail.com If you like, I can put this some place where others can get get directly Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- __ 73, Ray Xu KF5LJO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Racal-Dana 1992
DIY option for the 1992 I picked up mine as scrap. It did not have OCXO and the accuracy was terrible. I had been watching some 'bay auctions and most suitable OCXO were going for 30-40$.. one Christmas I put in a minimum bid and since most of you were away.. I got one for $5.50 ! You need a 5V oscillator. I used a perforated general purpose PCB and made a plug-in board for the OCXO and added a fine voltage control and mounted the pot on the back panel where there is an opening for the adjustment for the options. This is very simple DIY and should not give anyone trouble. I calibrate with the Rb unit and sometimes use the Rb units 10 Mhz out when I need a precise measurement. Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Racal-Dana 1992
Sounds just fine to me, and at a great price. Peter On Jan 31, 2012, at 11:12 PM, Raj vu2...@gmail.com wrote: DIY option for the 1992 I picked up mine as scrap. It did not have OCXO and the accuracy was terrible. I had been watching some 'bay auctions and most suitable OCXO were going for 30-40$.. one Christmas I put in a minimum bid and since most of you were away.. I got one for $5.50 ! You need a 5V oscillator. I used a perforated general purpose PCB and made a plug-in board for the OCXO and added a fine voltage control and mounted the pot on the back panel where there is an opening for the adjustment for the options. This is very simple DIY and should not give anyone trouble. I calibrate with the Rb unit and sometimes use the Rb units 10 Mhz out when I need a precise measurement. Cheers -- Raj, VU2ZAP Bangalore, India. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Prologix GPIB-ETH - Linux examples ?
On 1/31/12 12:34 PM, cfo wrote: On Mon, 30 Jan 2012 19:23:10 +, cfo wrote: I just got my Prologix GPIB-ETH I am 90% Linux Ubuntu based , and would like to get 99% based. So i am looking for some C code examples, implementing the linux networking part. Thanx for all the suggestions , i'll have a look at porting winsock apps to sockets. But i really like PHK's pylt , and will prob. give a prologic-eth driver a try. I have never tried python , but i hope i can ask for help on the net. After all i do have PHK's USB py driver as a nice skeleton. CFO Python is easy, once you get past the indenting for block structure thing.. It's a great way to do scripting. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
ken johnson wrote: Does anyone else have problems with links to tf.nist.gov? When I try to get the pdf's, I get no reply from the url at all. My browser puts out the request, but gets no reply whatsoever and eventually gives up. This also happened previously with this url tf.nist.gov redirects to: http://www.nist.gov/pml/div688/ Maybe that one will work? -- Bob Smither, PhD Circuit Concepts, Inc. = Blessed is he who expects no gratitude, for he shall not be disappointed. -- W. C. Bennett = smit...@c-c-i.com http://www.C-C-I.Com 281-331-2744(office) -4616(fax) attachment: smither.vcf___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GHz output from fe5680a
Does anyone else have problems with links to tf.nist.gov? When I try to get the pdf's, I get no reply from the url at all. My browser puts out the request, but gets no reply whatsoever and eventually gives up. This also happened previously with this url http://tf.boulder.nist.gov/general/pdf/2556.pdf I even tried turning my entire firewall off, but there is no reply coming back to allow through. Any ideas anyone? Or could someone temporarily put the .pdf's on a server somewhere so I can download them? .. or try using a proxy server, such as: http://www.freewebproxy.net/ Site is fine here, by the way, but I can't reach sdrsharp.com except through a proxy! Cheers, David -- SatSignal software - quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
