Re: [time-nuts] Space mission comes to an end becuase of a computer time tagging problem
albertson.ch...@gmail.com said: What stops working when things get cold? On Mars, the solar cells are pointed in the right direction. Why doesn't it recover when the sun comes back in the Spring? They run out of power for running the battery heaters, then the battery freezes and fails. The batteries get to such a low temperature that they are unable to be charged. The rover was never designed so that it could move and operate under solar power. It is really battery powered and uses the panel for charging. We are talking about running computers and radio gear rather than motors. I can see running motors in bursts from batteries, but computers and radios generally run continuously so they shouldn't need a battery when the sun is up. Am I missing something? Can't the computers and radios run off solar power when the batteries are dead? Does the receiver take more than (ballpark) peak solar-cell output under nasty conditions? jim...@earthlink.net said: That 10-20 degrees makes a big difference because of the cosine (angle) problem/ I understand that it could make the critical difference, but COS 20 is still close to 1. It's probably lost in the noise of how much dirt is on the solar cells. -- These are my opinions. I hate spam. ___ 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] JL LC_XO Performance
Thats correct, my opinion is obviously biased.. Here is a third party review of the unit (the Eurocan GPSTCXO version of the same product). http://jaunty-electronics.com/blog/2012/10/review-jackson-labs-gpstcxo-eval-board/ Hope that helps, Said On Sep 20, 2013, at 16:42, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Bob, Oh yes - but he would want to refrain from comment I would think. Regards, John On Fri, Sep 20, 2013 at 4:31 PM, Bob Camp li...@rtty.us wrote: Hi I'd bet that Said has seen a few of them ….. Bob On Sep 20, 2013, at 6:37 PM, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: So, I take it no one has looked at these units yet? Thanks, John Westmoreland On Thu, Sep 19, 2013 at 7:51 PM, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Hello All, I just spoke with JL - I should have one of the Jackson Labs' LC_XO's in my hands soon (TCXO option) - I was wondering if any of you have had a chance to look at it - and what your opinion is of the unit? If you have taken any detailed measurements you would like to share - that will be appreciated too. Also - if you have also taken a look at their GPSTCXO (TXCO option too) - how does it compare? Thanks In Advance, John Westmoreland ___ 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 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] JL LC_XO Performance
Said, I did not know this was the case as outlined in the article: Jackson Lab offers an extremely small (0.97″ x 0.97″), low-power (0.5 W) GPSDO module called ‘LC_XO’ [4http://www.jackson-labs.com/index.php/products/lc_xo]. The LC_XO is available as TCXO or more stable OCXO version. *It is electrically identical to the module populated on the eval board.* Thanks, John On Sat, Sep 21, 2013 at 11:05 PM, Said Jackson saidj...@aol.com wrote: Thats correct, my opinion is obviously biased.. Here is a third party review of the unit (the Eurocan GPSTCXO version of the same product). http://jaunty-electronics.com/blog/2012/10/review-jackson-labs-gpstcxo-eval-board/ Hope that helps, Said On Sep 20, 2013, at 16:42, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Bob, Oh yes - but he would want to refrain from comment I would think. Regards, John On Fri, Sep 20, 2013 at 4:31 PM, Bob Camp li...@rtty.us wrote: Hi I'd bet that Said has seen a few of them ….. Bob On Sep 20, 2013, at 6:37 PM, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: So, I take it no one has looked at these units yet? Thanks, John Westmoreland On Thu, Sep 19, 2013 at 7:51 PM, John C. Westmoreland, P.E. j...@westmorelandengineering.com wrote: Hello All, I just spoke with JL - I should have one of the Jackson Labs' LC_XO's in my hands soon (TCXO option) - I was wondering if any of you have had a chance to look at it - and what your opinion is of the unit? If you have taken any detailed measurements you would like to share - that will be appreciated too. Also - if you have also taken a look at their GPSTCXO (TXCO option too) - how does it compare? Thanks In Advance, John Westmoreland ___ 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 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] Space mission comes to an end becuase of a computer time tagging problem
There is a major problem with Radioisotope Thermoelectric Generators Our stocks of Plutonium-238 are very low -- less than 40 pounds remain available to NASA and this is all spoken for future missions. We are restarting the manufacture and it is supposed to come online sometime around 2017. One gram of Plutonium-238 gives about 0.5 watts of deliverable electricity. Half-life of 87.7 years. P-238 does not go KaBoom! -- you are thinking of P-239. http://en.wikipedia.org/wiki/Plutonium-238 http://www.space.com/20290-plutonium-spacecraft-nasa-fuel.html http://www.wired.com/wiredscience/2013/09/plutonium-238-history-timeline/ -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Chris Albertson Sent: Saturday, September 21, 2013 20:34 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Space mission comes to an end becuase of a computer time tagging problem On Sat, Sep 21, 2013 at 6:40 PM, Hal Murray hmur...@megapathdsl.net wrote: What stops working when things get cold? On Mars, the solar cells are pointed in the right direction. Why doesn't it recover when the sun comes back in the Spring? They run out of power for running the battery heaters, then the battery freezes and fails. The batteries get to such a low temperature that they are unable to be charged. The rover was never designed so that it could move and operate under solar power. It is really battery powered and uses the panel for charging. This is the biggest reason the newest rover, Curiosity is powered by an RTG, not solar cells. The RTG is powered by radioactive decay. The thing makes a lot of heat and should last 15 to 20 years. Likely longer than all the moving parts like motors and so on. -- 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 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] Reflections and Low Phase Noise
On 09/22/2013 02:35 AM, Hal Murray wrote: For those that have not been in Boulder, you should realize that it is just downhill from the mountains. Multiple small creeks run through Boulder as the rain poors off the Rocky Mountains, like the Flatirons that dominate the view of Boulder. Boulder really stops at the Rocky Mountains. Except the creeks aren't so small when it rains hard. They have a large collection basin. Which is my point. By giving an image of how these usually nice little creeks goes through Boulder, you then realize how much damage they can do when there is a lot of water. 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 Loop Lock Indicator
Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot higher, to load the FE-5680 less. The PN has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor. Bob LaJeunesse From: Bob Stewart b...@evoria.net To: Time Nuts time-nuts@febo.com Sent: Saturday, September 21, 2013 10:02 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi John, Thanks for the response. I managed to cobble something up with LTSpiceIV, and get it to work. And for me, that's saying something!Here's what I wound up with: http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png;, where V2 is the Loop Lock Indicator. The PN shorts out the LED until it goes into lock, then the LED comes on. It does give a short pulse when power is first applied and things are equalizing. Even with a 1K resistor, the 4.2V from Lock signal is pulled down to 3V. And here's a pic of my Rb standard on it's temporary home with the LED on a scrap of breadboard: http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png;. Bob From: jmfranke jmfra...@cox.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 6:58 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Yes, but put an isolation resistor between the output and the base of the transistor, something between 3K and 5K should work. The LED will light upon power on and extinguish when lock is achieved. John WA4WDL -- From: Bob Stewart b...@evoria.net Sent: Saturday, September 21, 2013 6:10 PM To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Bob, I hooked the big voltmeter up to it, and it shows +4.2V out for about a minute, and then goes to 0. Looking on the web, it seems like I can use that to drive a 2N and put the LED and dropping resistor in the collector path with the emitter to ground? Does that sound right? Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 4:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Those readings sound a lot more like a CMOS gate output than some sort of open drain / open collector discrete driver. Bob On Sep 21, 2013, at 4:43 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, It's rather curious. Using my handheld DVM in the diode scale, I get a reading of 448 in one direction and 458 in the other with it off and cold. In the 2K ohms scale, I get 561 and 562 ohms. Later on, I'll pop the top off again and take a pic so I can expand it and look at it. For what it's worth, my DDS board is 2 revisions earlier than the one Matthias Bopp modifies here http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%201_0.pdf; Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 3:00 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi As far as I know the lock output is a CMOS output that will drive a couple of ma. There are so many variations that yours may indeed be an open collector and good to +15 volts. Bob On Sep 21, 2013, at 10:55 AM, Bob Stewart b...@evoria.net wrote: The instructions I got with this Rb said that you could hook an LED through a 5-10K resistor to the +15 supply and get a lock indication. I'm using a 10K resistor and the LED lights as soon as it's powered up from cold. Is the loop lock indicator circuit broken or is it just another strange option
[time-nuts] How To Measure Long Term Phase Stability Of An Oscillator
How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. Jeff ___ 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] How To Measure Long Term Phase Stability Of An Oscillator
On 09/22/2013 01:30 PM, W3KL wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. You want to measure a drift of 4/(4E6*3600) = 278 ps. You systematic frequency error can be at maximum 1.39E-10 relative, For your noise side look at TDEV at tau of 4 s, multiply that number by at least three and it should when added with peak frequency error be below 278 ps. 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] How To Measure Long Term Phase Stability Of An Oscillator
Time interval counter? On Sun, Sep 22, 2013 at 1:30 PM, W3KL w...@w3kl.com wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. Jeff ___ 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] How To Measure Long Term Phase Stability Of An Oscillator
Hi I think he needs 16X better than that (0.1 degrees in 4 seconds) so it's 1/(4*4e6*3600). That's right around 2x10^-11, so you would need a system that's good to maybe 2x10^-12 to do the trick. The easy approach is to build several of the same oscillator and compare them to each other. The assumption would be that the drift will be random over the 4 second period. Bob On Sep 22, 2013, at 7:47 AM, Magnus Danielson mag...@rubidium.dyndns.org wrote: On 09/22/2013 01:30 PM, W3KL wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. You want to measure a drift of 4/(4E6*3600) = 278 ps. You systematic frequency error can be at maximum 1.39E-10 relative, For your noise side look at TDEV at tau of 4 s, multiply that number by at least three and it should when added with peak frequency error be below 278 ps. 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 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] How To Measure Long Term Phase Stability Of An Oscillator
Magnus. Thanks. If I understand, this reduces to a measurement of frequency stability along a measurement of phase noise? Jeff -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Sunday, September 22, 2013 7:47 AM To: time-nuts@febo.com Subject: Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator On 09/22/2013 01:30 PM, W3KL wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. You want to measure a drift of 4/(4E6*3600) = 278 ps. You systematic frequency error can be at maximum 1.39E-10 relative, For your noise side look at TDEV at tau of 4 s, multiply that number by at least three and it should when added with peak frequency error be below 278 ps. 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 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] How To Measure Long Term Phase Stability Of An Oscillator
Hi All you really need to do is to measure the frequency stability to the ppt level. There's no real need to measure phase noise. Bob On Sep 22, 2013, at 8:01 AM, W3KL w...@w3kl.com wrote: Magnus. Thanks. If I understand, this reduces to a measurement of frequency stability along a measurement of phase noise? Jeff -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Sunday, September 22, 2013 7:47 AM To: time-nuts@febo.com Subject: Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator On 09/22/2013 01:30 PM, W3KL wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. You want to measure a drift of 4/(4E6*3600) = 278 ps. You systematic frequency error can be at maximum 1.39E-10 relative, For your noise side look at TDEV at tau of 4 s, multiply that number by at least three and it should when added with peak frequency error be below 278 ps. 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 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] Space mission comes to an end becuase of a computer time tagging problem
On 9/21/13 11:03 PM, Hal Murray wrote: albertson.ch...@gmail.com said: What stops working when things get cold? On Mars, the solar cells are pointed in the right direction. Why doesn't it recover when the sun comes back in the Spring? They run out of power for running the battery heaters, then the battery freezes and fails. The batteries get to such a low temperature that they are unable to be charged. The rover was never designed so that it could move and operate under solar power. It is really battery powered and uses the panel for charging. We are talking about running computers and radio gear rather than motors. I can see running motors in bursts from batteries, but computers and radios generally run continuously so they shouldn't need a battery when the sun is up. The computers and radios and instruments actually take more power than the motors. MER doesn't have very big motors. It only moves a few cm/sec. For instance, to fire up the radio to talk to earth, either via the relay link or direct on X-band, is probably around 50 watts. MER has maybe 1 square meter of solar panels, it's farther from the sun, etc. It probably has positive energy balance when the sun is shining in the summer and running the flight computer and radios. The problem is running the heaters in the cold. In the winter, it gets colder AND there's less solar energy from the panels. ___ 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 Loop Lock Indicator
Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot higher, to load the FE-5680 less. The PN has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor. Bob LaJeunesse From: Bob Stewart b...@evoria.net To: Time Nuts time-nuts@febo.com Sent: Saturday, September 21, 2013 10:02 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi John, Thanks for the response. I managed to cobble something up with LTSpiceIV, and get it to work. And for me, that's saying something! Here's what I wound up with: http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png;, where V2 is the Loop Lock Indicator. The PN shorts out the LED until it goes into lock, then the LED comes on. It does give a short pulse when power is first applied and things are equalizing. Even with a 1K resistor, the 4.2V from Lock signal is pulled down to 3V. And here's a pic of my Rb standard on it's temporary home with the LED on a scrap of breadboard: http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png;. Bob From: jmfranke jmfra...@cox.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 6:58 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Yes, but put an isolation resistor between the output and the base of the transistor, something between 3K and 5K should work. The LED will light upon power on and extinguish when lock is achieved. John WA4WDL -- From: Bob Stewart b...@evoria.net Sent: Saturday, September 21, 2013 6:10 PM To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Bob, I hooked the big voltmeter up to it, and it shows +4.2V out for about a minute, and then goes to 0. Looking on the web, it seems like I can use that to drive a 2N and put the LED and dropping resistor in the collector path with the emitter to ground? Does that sound right? Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 4:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Those readings sound a lot more like a CMOS gate output than some sort of open drain / open collector discrete driver. Bob On Sep 21, 2013, at 4:43 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, It's rather curious. Using my handheld DVM in the diode scale, I get a reading of 448 in one direction and 458 in the other with it off and cold. In the 2K ohms scale, I get 561 and 562 ohms. Later on, I'll pop the top off again and take a pic so I can expand it and look at it. For what it's worth, my DDS board is 2 revisions earlier than the one Matthias Bopp modifies here http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%201_0.pdf; Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September
Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator
Jeff, You need to measure phase with sufficient resolution and rate of time. I was vague on the equipment side but rater noted what you needed to do in the analysis-side. I would prefer to measure it at least with 10 measurements a second. Bob mentioned resolution, which is important as you don't want your measurement being swamped by measurement noise. I would use a TimePod, but not all of us have one, which is a pitty as it is a good instrument suitable for exactly this. Cheers, Magnus On 09/22/2013 02:01 PM, W3KL wrote: Magnus. Thanks. If I understand, this reduces to a measurement of frequency stability along a measurement of phase noise? Jeff -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Sunday, September 22, 2013 7:47 AM To: time-nuts@febo.com Subject: Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator On 09/22/2013 01:30 PM, W3KL wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. You want to measure a drift of 4/(4E6*3600) = 278 ps. You systematic frequency error can be at maximum 1.39E-10 relative, For your noise side look at TDEV at tau of 4 s, multiply that number by at least three and it should when added with peak frequency error be below 278 ps. 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 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] Space mission comes to an end becuase of a computer time tagging problem
Well, since this thread has recurred and there seem to be people with good knowledge here, I've got to ask how a spacecraft that has lost its ability to aim antennas at Earth or align solar panels with the sun could possibly be diagnosed with having a time tagging problem? Jim Lux pretty well demolished the idea that time had anything to do with it, IMHO. Seems to me that the DSN doesn't listen to Deep Impact continuously because it has other spacecraft to track. So there's no growing anomaly to indicate a future problem. One time communication is fine, the next time there is no answer. Pretty difficult to diagnose a problem from those symptoms. Used silver cell batteries for an upper atmosphere density probe in 1958. They're still around, but not suitable for long missions. What kind of battery (not RTG) would a deep space probe use? Thanks for any answers. Bill Hawkins ___ 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 Loop Lock Indicator
Hi Circuit should be: 2N with emitter to ground, collector to LED, base to lock indicator via the 4.7K resistor. The LED is hooked to +15 via another resistor. If you have ~ 10 ma in the LED then the base needs less than 0.1 ma to do the job with a . A 4.7K should be plenty. Alternate circuit: 2N with base to lock indicator / no resistor at all, emitter to ground via a 1K resistor, collector to LED. LED to +15 via a 1.5K resistor. Either one should work. Both turn on the LED when the output is high and off when the output is low. In order to turn on when it's high you need to get an inversion ahead of the 2N. Bob On Sep 22, 2013, at 12:17 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot higher, to load the FE-5680 less. The PN has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor. Bob LaJeunesse From: Bob Stewart b...@evoria.net To: Time Nuts time-nuts@febo.com Sent: Saturday, September 21, 2013 10:02 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi John, Thanks for the response. I managed to cobble something up with LTSpiceIV, and get it to work. And for me, that's saying something!Here's what I wound up with: http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png;, where V2 is the Loop Lock Indicator. The PN shorts out the LED until it goes into lock, then the LED comes on. It does give a short pulse when power is first applied and things are equalizing. Even with a 1K resistor, the 4.2V from Lock signal is pulled down to 3V. And here's a pic of my Rb standard on it's temporary home with the LED on a scrap of breadboard: http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png;. Bob From: jmfranke jmfra...@cox.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 6:58 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Yes, but put an isolation resistor between the output and the base of the transistor, something between 3K and 5K should work. The LED will light upon power on and extinguish when lock is achieved. John WA4WDL -- From: Bob Stewart b...@evoria.net Sent: Saturday, September 21, 2013 6:10 PM To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Bob, I hooked the big voltmeter up to it, and it shows +4.2V out for about a minute, and then goes to 0. Looking on the web, it seems like I can use that to drive a 2N and put the LED and dropping resistor in the collector path with the emitter to ground? Does that sound right? Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 4:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Those readings sound a lot more like a CMOS gate output than some sort of open drain / open collector discrete
Re: [time-nuts] FE-5680A Loop Lock Indicator
Except that it doesn't work with even 1500 ohms in the base lead. The LED immediately comes on and stays on. I could increase the emitter resistor to 1500 ohms and get around 8.5-9ma through the LED, but I'm done playing with it until I get a proper box to put it all in. This is just a random 3mm LED out of an HP 37203A, so maybe that has something to do with it? I haven't looked at the specs. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Circuit should be: 2N with emitter to ground, collector to LED, base to lock indicator via the 4.7K resistor. The LED is hooked to +15 via another resistor. If you have ~ 10 ma in the LED then the base needs less than 0.1 ma to do the job with a . A 4.7K should be plenty. Alternate circuit: 2N with base to lock indicator / no resistor at all, emitter to ground via a 1K resistor, collector to LED. LED to +15 via a 1.5K resistor. Either one should work. Both turn on the LED when the output is high and off when the output is low. In order to turn on when it's high you need to get an inversion ahead of the 2N. Bob On Sep 22, 2013, at 12:17 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot higher, to load the FE-5680 less. The PN has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor. Bob LaJeunesse From: Bob Stewart b...@evoria.net To: Time Nuts time-nuts@febo.com Sent: Saturday, September 21, 2013 10:02 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi John, Thanks for the response. I managed to cobble something up with LTSpiceIV, and get it to work. And for me, that's saying something! Here's what I wound up with: http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png;, where V2 is the Loop Lock Indicator. The PN shorts out the LED until it goes into lock, then the LED comes on. It does give a short pulse when power is first applied and things are equalizing. Even with a 1K resistor, the 4.2V from Lock signal is pulled down to 3V. And here's a pic of my Rb standard on it's temporary home with the LED on a scrap of breadboard: http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png;. Bob From: jmfranke jmfra...@cox.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 6:58 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Yes, but put an isolation resistor between the output and the base of the transistor, something between 3K and 5K should work. The LED will light upon power on and extinguish when lock is achieved. John WA4WDL -- From: Bob Stewart b...@evoria.net Sent: Saturday, September 21, 2013 6:10 PM To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Bob, I hooked
Re: [time-nuts] FE-5680A Loop Lock Indicator
D'oh, that should say I could increase the COLLECTOR resistor to 1500 ohms. From: Bob Stewart b...@evoria.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:27 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Except that it doesn't work with even 1500 ohms in the base lead. The LED immediately comes on and stays on. I could increase the emitter resistor to 1500 ohms and get around 8.5-9ma through the LED, but I'm done playing with it until I get a proper box to put it all in. This is just a random 3mm LED out of an HP 37203A, so maybe that has something to do with it? I haven't looked at the specs. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Circuit should be: 2N with emitter to ground, collector to LED, base to lock indicator via the 4.7K resistor. The LED is hooked to +15 via another resistor. If you have ~ 10 ma in the LED then the base needs less than 0.1 ma to do the job with a . A 4.7K should be plenty. Alternate circuit: 2N with base to lock indicator / no resistor at all, emitter to ground via a 1K resistor, collector to LED. LED to +15 via a 1.5K resistor. Either one should work. Both turn on the LED when the output is high and off when the output is low. In order to turn on when it's high you need to get an inversion ahead of the 2N. Bob On Sep 22, 2013, at 12:17 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot higher, to load the FE-5680 less. The PN has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor. Bob LaJeunesse From: Bob Stewart b...@evoria.net To: Time Nuts time-nuts@febo.com Sent: Saturday, September 21, 2013 10:02 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi John, Thanks for the response. I managed to cobble something up with LTSpiceIV, and get it to work. And for me, that's saying something! Here's what I wound up with: http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png;, where V2 is the Loop Lock Indicator. The PN shorts out the LED until it goes into lock, then the LED comes on. It does give a short pulse when power is first applied and things are equalizing. Even with a 1K resistor, the 4.2V from Lock signal is pulled down to 3V. And here's a pic of my Rb standard on it's temporary home with the LED on a scrap of breadboard: http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png;. Bob From: jmfranke jmfra...@cox.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 6:58 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Yes, but put an isolation resistor between the output and the base of the transistor, something between 3K and 5K should work. The LED will light upon power on and extinguish when
Re: [time-nuts] FE-5680A Loop Lock Indicator
Hi If you want 10 ma through the LED (which should be plenty) then the collector resistor would be right around 1.2K Bob On Sep 22, 2013, at 1:32 PM, Bob Stewart b...@evoria.net wrote: D'oh, that should say I could increase the COLLECTOR resistor to 1500 ohms. From: Bob Stewart b...@evoria.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:27 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Except that it doesn't work with even 1500 ohms in the base lead. The LED immediately comes on and stays on. I could increase the emitter resistor to 1500 ohms and get around 8.5-9ma through the LED, but I'm done playing with it until I get a proper box to put it all in. This is just a random 3mm LED out of an HP 37203A, so maybe that has something to do with it? I haven't looked at the specs. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Circuit should be: 2N with emitter to ground, collector to LED, base to lock indicator via the 4.7K resistor. The LED is hooked to +15 via another resistor. If you have ~ 10 ma in the LED then the base needs less than 0.1 ma to do the job with a . A 4.7K should be plenty. Alternate circuit: 2N with base to lock indicator / no resistor at all, emitter to ground via a 1K resistor, collector to LED. LED to +15 via a 1.5K resistor. Either one should work. Both turn on the LED when the output is high and off when the output is low. In order to turn on when it's high you need to get an inversion ahead of the 2N. Bob On Sep 22, 2013, at 12:17 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot higher, to load the FE-5680 less. The PN has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor. Bob LaJeunesse From: Bob Stewart b...@evoria.net To: Time Nuts time-nuts@febo.com Sent: Saturday, September 21, 2013 10:02 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi John, Thanks for the response. I managed to cobble something up with LTSpiceIV, and get it to work. And for me, that's saying something!Here's what I wound up with: http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png;, where V2 is the Loop Lock Indicator. The PN shorts out the LED until it goes into lock, then the LED comes on. It does give a short pulse when power is first applied and things are equalizing. Even with a 1K resistor, the 4.2V from Lock signal is pulled down to 3V. And here's a pic of my Rb standard on it's temporary home with the LED on a scrap of breadboard: http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png;. Bob From: jmfranke jmfra...@cox.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 6:58 PM
Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator
Magnus. Thanks. Re-read your original post and along with your latest I now understand what's needed. I will come back if I have other questions. Thanks! Jeff -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Sunday, September 22, 2013 1:02 PM To: time-nuts@febo.com Subject: Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator Jeff, You need to measure phase with sufficient resolution and rate of time. I was vague on the equipment side but rater noted what you needed to do in the analysis-side. I would prefer to measure it at least with 10 measurements a second. Bob mentioned resolution, which is important as you don't want your measurement being swamped by measurement noise. I would use a TimePod, but not all of us have one, which is a pitty as it is a good instrument suitable for exactly this. Cheers, Magnus On 09/22/2013 02:01 PM, W3KL wrote: Magnus. Thanks. If I understand, this reduces to a measurement of frequency stability along a measurement of phase noise? Jeff -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Sunday, September 22, 2013 7:47 AM To: time-nuts@febo.com Subject: Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator On 09/22/2013 01:30 PM, W3KL wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. You want to measure a drift of 4/(4E6*3600) = 278 ps. You systematic frequency error can be at maximum 1.39E-10 relative, For your noise side look at TDEV at tau of 4 s, multiply that number by at least three and it should when added with peak frequency error be below 278 ps. 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 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] FE-5680A Loop Lock Indicator
I have a circuit that seems to work well: The lock indicator is a weak source but a good sink so it interfaces more naturally with a pnp or p-channel device. Pull it up to 5V with 100K and connect this point to the gate of a P channel Mosfet whose source is also connected to 5V. Connect the drain of the mosfet to a LED anode and take the LED cathode via 220 R to 0V. This way, the sense of the indicator is correct (0n = lock) and the drive capability of the lock signal works in your favour. Chris Stake -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: 22 September 2013 18:53 To: Bob Stewart; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you want 10 ma through the LED (which should be plenty) then the collector resistor would be right around 1.2K Bob On Sep 22, 2013, at 1:32 PM, Bob Stewart b...@evoria.net wrote: D'oh, that should say I could increase the COLLECTOR resistor to 1500 ohms. From: Bob Stewart b...@evoria.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:27 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Except that it doesn't work with even 1500 ohms in the base lead. The LED immediately comes on and stays on. I could increase the emitter resistor to 1500 ohms and get around 8.5-9ma through the LED, but I'm done playing with it until I get a proper box to put it all in. This is just a random 3mm LED out of an HP 37203A, so maybe that has something to do with it? I haven't looked at the specs. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Circuit should be: 2N with emitter to ground, collector to LED, base to lock indicator via the 4.7K resistor. The LED is hooked to +15 via another resistor. If you have ~ 10 ma in the LED then the base needs less than 0.1 ma to do the job with a . A 4.7K should be plenty. Alternate circuit: 2N with base to lock indicator / no resistor at all, emitter to ground via a 1K resistor, collector to LED. LED to +15 via a 1.5K resistor. Either one should work. Both turn on the LED when the output is high and off when the output is low. In order to turn on when it's high you need to get an inversion ahead of the 2N. Bob On Sep 22, 2013, at 12:17 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot higher, to load the FE- 5680 less. The PN has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor. Bob LaJeunesse From: Bob Stewart b...@evoria.net To: Time Nuts time-nuts@febo.com Sent: Saturday, September 21, 2013 10:02 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi John, Thanks for the response. I managed to cobble something up with LTSpiceIV, and get
[time-nuts] HP5061B Beam Tubes
What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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] HP5061B Beam Tubes
Hi Most of the genuine 5061 tubes out there have either died long ago or wound up in one of the ever smaller number of working 5061's. Bob On Sep 22, 2013, at 3:58 PM, W3KL w...@w3kl.com wrote: What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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] How To Measure Long Term Phase Stability Of An Oscillator
Jeff, Sorry if I was unclear in the first message, but I was tired. The factor of 3 that I have in the first message is a huge approximation, and could be a higher value for higher confidence interval. It's an attempt to handle the chi-square distribution margin for some probability of staying within. I used 3, as the traditional engineering margin for the usual gaussian distribution, mostly because I was to tired to dig up the propper value, but it doesn't really care as it is an approximation never the less and in the right direction. The underlying point is that you need to estimate the systematic and random effects separately, and then fit them together with their quite drastic different probability behaviors. You can't use either of the tools as the single tool, unless you have a fairly good idea of the dominant part, which I can't in this case. I discussed this point with Dr. Allan, and he only knew of a pair of articles even covering this aspect, but he agreed on the overall approach. Cheers, Magnus On 09/22/2013 08:43 PM, W3KL wrote: Magnus. Thanks. Re-read your original post and along with your latest I now understand what's needed. I will come back if I have other questions. Thanks! Jeff -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Sunday, September 22, 2013 1:02 PM To: time-nuts@febo.com Subject: Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator Jeff, You need to measure phase with sufficient resolution and rate of time. I was vague on the equipment side but rater noted what you needed to do in the analysis-side. I would prefer to measure it at least with 10 measurements a second. Bob mentioned resolution, which is important as you don't want your measurement being swamped by measurement noise. I would use a TimePod, but not all of us have one, which is a pitty as it is a good instrument suitable for exactly this. Cheers, Magnus On 09/22/2013 02:01 PM, W3KL wrote: Magnus. Thanks. If I understand, this reduces to a measurement of frequency stability along a measurement of phase noise? Jeff -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: Sunday, September 22, 2013 7:47 AM To: time-nuts@febo.com Subject: Re: [time-nuts] How To Measure Long Term Phase Stability Of An Oscillator On 09/22/2013 01:30 PM, W3KL wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. You want to measure a drift of 4/(4E6*3600) = 278 ps. You systematic frequency error can be at maximum 1.39E-10 relative, For your noise side look at TDEV at tau of 4 s, multiply that number by at least three and it should when added with peak frequency error be below 278 ps. 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 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 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 Loop Lock Indicator
I hadn't thought of using a pullup resistor. I'd have to get out the calculator to see if it's worth it, though. It's only taking a load for a minute or two till it locks, so I don't think it's a problem. Bob From: Chris Stake st...@btinternet.com To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com; 'Bob Stewart' b...@evoria.net Sent: Sunday, September 22, 2013 2:06 PM Subject: RE: [time-nuts] FE-5680A Loop Lock Indicator I have a circuit that seems to work well: The lock indicator is a weak source but a good sink so it interfaces more naturally with a pnp or p-channel device. Pull it up to 5V with 100K and connect this point to the gate of a P channel Mosfet whose source is also connected to 5V. Connect the drain of the mosfet to a LED anode and take the LED cathode via 220 R to 0V. This way, the sense of the indicator is correct (0n = lock) and the drive capability of the lock signal works in your favour. Chris Stake -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: 22 September 2013 18:53 To: Bob Stewart; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you want 10 ma through the LED (which should be plenty) then the collector resistor would be right around 1.2K Bob On Sep 22, 2013, at 1:32 PM, Bob Stewart b...@evoria.net wrote: D'oh, that should say I could increase the COLLECTOR resistor to 1500 ohms. From: Bob Stewart b...@evoria.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:27 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Except that it doesn't work with even 1500 ohms in the base lead. The LED immediately comes on and stays on. I could increase the emitter resistor to 1500 ohms and get around 8.5-9ma through the LED, but I'm done playing with it until I get a proper box to put it all in. This is just a random 3mm LED out of an HP 37203A, so maybe that has something to do with it? I haven't looked at the specs. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 12:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Circuit should be: 2N with emitter to ground, collector to LED, base to lock indicator via the 4.7K resistor. The LED is hooked to +15 via another resistor. If you have ~ 10 ma in the LED then the base needs less than 0.1 ma to do the job with a . A 4.7K should be plenty. Alternate circuit: 2N with base to lock indicator / no resistor at all, emitter to ground via a 1K resistor, collector to LED. LED to +15 via a 1.5K resistor. Either one should work. Both turn on the LED when the output is high and off when the output is low. In order to turn on when it's high you need to get an inversion ahead of the 2N. Bob On Sep 22, 2013, at 12:17 PM, Bob Stewart b...@evoria.net wrote: Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp li...@rtty.us To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets you even less output than you would expect from a CMOS gate. I would not count on it putting out more than 1 ma at 5 volts. A 4.7K resistor to the 2N base should be about right. Bob On Sep 21, 2013, at 10:34 PM, Bob Stewart b...@evoria.net wrote: Thanks for the heads-up, Bob. I'll do it the next time the iron is hot. Fortunately, it's only on for about a minute or so, then there's no drive from the FE-5680A. Is 3ma really that big a deal? I know squat about CMOS gates. I guess it is pulling the voltage down by 25%, though. Bob From: Robert LaJeunesse rlajeune...@sbcglobal.net To: Bob Stewart b...@evoria.net; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Saturday, September 21, 2013 9:24 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Bob, I would bump that base resistor up a lot
Re: [time-nuts] HP5061B Beam Tubes
Bob basically said it, not only 5061A but most others. I now only run my 5061A every couple months to purge it and when I want to play with my two Rb's and want them adjusted to the 5061A vs GPS. Wonder what a replacement 5071A tube runs now days ... -pete On Sun, Sep 22, 2013 at 1:36 PM, Bob Camp li...@rtty.us wrote: Hi Most of the genuine 5061 tubes out there have either died long ago or wound up in one of the ever smaller number of working 5061's. Bob On Sep 22, 2013, at 3:58 PM, W3KL w...@w3kl.com wrote: What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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] HP5061B Beam Tubes
Hi Well I can answer that one. Sending a 5071 back to Symmetricom and getting a new high performance tube in it is roughly a $35K hit to the old Visa card. The hard part is getting all the shipping doc's filled out for the ultra hazardous Cs that you are shipping. You have to go to a class and get a certificate just to fill out the forms…. Perish forbid *anybody* would ever ignore those regulations and carry one on a passenger flight ……. -- Just in case you missed all the previous posts. There isn't enough Cs in a standard to harm much of anything Its so well protected that a drop off a 4 story building won't release any of it. Regardless of all that it's Hazmat. Bob On Sep 22, 2013, at 5:32 PM, Pete Lancashire p...@petelancashire.com wrote: Bob basically said it, not only 5061A but most others. I now only run my 5061A every couple months to purge it and when I want to play with my two Rb's and want them adjusted to the 5061A vs GPS. Wonder what a replacement 5071A tube runs now days ... -pete On Sun, Sep 22, 2013 at 1:36 PM, Bob Camp li...@rtty.us wrote: Hi Most of the genuine 5061 tubes out there have either died long ago or wound up in one of the ever smaller number of working 5061's. Bob On Sep 22, 2013, at 3:58 PM, W3KL w...@w3kl.com wrote: What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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 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] HP5061B Beam Tubes
No mention of price or availability (this is a 1999 document) but KO4BB has this: http://www.ko4bb.com/Manuals/HP_Agilent/HP_5061A_Cesium_Beam_Frequency_Stand ard/datum_replacement_cs_tube_5061a_specs.pdf Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Pete Lancashire Sent: Sunday, September 22, 2013 14:33 To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] HP5061B Beam Tubes Bob basically said it, not only 5061A but most others. I now only run my 5061A every couple months to purge it and when I want to play with my two Rb's and want them adjusted to the 5061A vs GPS. Wonder what a replacement 5071A tube runs now days ... -pete On Sun, Sep 22, 2013 at 1:36 PM, Bob Camp li...@rtty.us wrote: Hi Most of the genuine 5061 tubes out there have either died long ago or wound up in one of the ever smaller number of working 5061's. Bob On Sep 22, 2013, at 3:58 PM, W3KL w...@w3kl.com wrote: What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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 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] How To Measure Long Term Phase Stability Of An Oscillator
On Sun, Sep 22, 2013 at 4:30 AM, W3KL w...@w3kl.com wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. The simplest way to first to get a very much better oscillator than the one you need to test. You need a refference. Then you add them and if there is any deference at all you will get a beat frequency If the two are close the beat will be very slow, slow enough you can measure the period with a wrst watch. Put the two on a daul channel scope nd watch. More sofesticaed method is to use a transformer to add the two signals then feed the sun into a computer's audio input or otherwise record the beat frequency. You can do an FFT on the recording. I sure others will have even better methods but my point is that simple technique can work, provided you have a really god reference oscillator. -- 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] How To Measure Long Term Phase Stability Of An Oscillator
Hi In this case it would need to be a really good oscillator at or very near 4 MHz. That's not a real common frequency. Yes you could double 10 MHz and then divide by 5, but that has it's own issues….. Bob On Sep 22, 2013, at 6:15 PM, Chris Albertson albertson.ch...@gmail.com wrote: On Sun, Sep 22, 2013 at 4:30 AM, W3KL w...@w3kl.com wrote: How does one make a measurement of the phase stability of an oscillator over a time period much larger than the oscillator period? For example, I have an oscillator with a frequency of 4 MHz and I want to measure the phase drift of the RF between a given point in time and then a time 4 seconds later. I want to make a measurement that has a precision of 0.1 degree or better. The simplest way to first to get a very much better oscillator than the one you need to test. You need a refference. Then you add them and if there is any deference at all you will get a beat frequency If the two are close the beat will be very slow, slow enough you can measure the period with a wrst watch. Put the two on a daul channel scope nd watch. More sofesticaed method is to use a transformer to add the two signals then feed the sun into a computer's audio input or otherwise record the beat frequency. You can do an FFT on the recording. I sure others will have even better methods but my point is that simple technique can work, provided you have a really god reference oscillator. -- 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 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] HP5061B Beam Tubes
The HP and Symmetricom Cesium standards have a hazmat exemption. Thomas Knox From: li...@rtty.us Date: Sun, 22 Sep 2013 17:46:18 -0400 To: time-nuts@febo.com Subject: Re: [time-nuts] HP5061B Beam Tubes Hi Well I can answer that one. Sending a 5071 back to Symmetricom and getting a new high performance tube in it is roughly a $35K hit to the old Visa card. The hard part is getting all the shipping doc's filled out for the ultra hazardous Cs that you are shipping. You have to go to a class and get a certificate just to fill out the forms…. Perish forbid *anybody* would ever ignore those regulations and carry one on a passenger flight ……. -- Just in case you missed all the previous posts. There isn't enough Cs in a standard to harm much of anything Its so well protected that a drop off a 4 story building won't release any of it. Regardless of all that it's Hazmat. Bob On Sep 22, 2013, at 5:32 PM, Pete Lancashire p...@petelancashire.com wrote: Bob basically said it, not only 5061A but most others. I now only run my 5061A every couple months to purge it and when I want to play with my two Rb's and want them adjusted to the 5061A vs GPS. Wonder what a replacement 5071A tube runs now days ... -pete On Sun, Sep 22, 2013 at 1:36 PM, Bob Camp li...@rtty.us wrote: Hi Most of the genuine 5061 tubes out there have either died long ago or wound up in one of the ever smaller number of working 5061's. Bob On Sep 22, 2013, at 3:58 PM, W3KL w...@w3kl.com wrote: What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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 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] Space mission comes to an end becuase of a computer time tagging problem
On 9/22/13 10:07 AM, Bill Hawkins wrote: Well, since this thread has recurred and there seem to be people with good knowledge here, I've got to ask how a spacecraft that has lost its ability to aim antennas at Earth or align solar panels with the sun could possibly be diagnosed with having a time tagging problem? Most likely because the telemetry (which is time tagged in several ways) didn't make sense. If you got frames down and the spacecraft time wasn't monotonically increasing, you're pretty sure you've had a reset. For that matter, there's a sequence number in the transfer frames, and if that reset, you'd see it. I don't know what the format of the DI telemetry frame is (it's probably published.. in general, telemetry isn't export controlled) but a typical scheme has the SCLK (spacecraft clock) in every frame, or every N frames. The question is whether they have all the bits of sclk all the time, or just the LSBs all the time, and the MSBs occasionally. DI is a fairly old design, so the telemetry format probably isn't very complex (e.g. it's not like they have dynamically allocated data fields, etc.) Jim Lux pretty well demolished the idea that time had anything to do with it, IMHO. Seems to me that the DSN doesn't listen to Deep Impact continuously because it has other spacecraft to track. Yes. There's probably 50 spacecraft that DSN is tracking. As I recall, they track Voyager once a week or maybe every other week. There's actually a published schedule on a regularly updated website. So there's no growing anomaly to indicate a future problem. One time communication is fine, the next time there is no answer. Pretty difficult to diagnose a problem from those symptoms. Well.. if the s/c is in safe mode, it's sending data at something like 10bps or 7-8 bps. And that data will have a sequence number or clock time in it, and you might be able to infer what's going on from that. Or, they have a trickle back scheme that sends a few words of memory in every frame, so that after enough frames, you have an image of memory. Used silver cell batteries for an upper atmosphere density probe in 1958. They're still around, but not suitable for long missions. What kind of battery (not RTG) would a deep space probe use? for rechargeable? NiCd (in the past) Lithium Ion (now) A lot also depends on temperature range expected. Most orbiters even around Mars, stay nice and toasty warm without much work, as long as the thermal design was decent. A shiny metal ball in orbit around Mars will get quite warm. I don't know if it would get to 60-78C, but it definitely will get to 30C. It's all about alpha/epsilon ratios. But different battery chemistry has different temperature range tolerances. And then, there's the whole will it have charge after it thaws question. I have some supercaps that I've been meaning to freeze to try it out (or at least to see if they'll survive) ___ 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] HP5061B Beam Tubes
Hi If so Symmetricom is not aware of that and neither is FedEx or UPS. When you ship in your 5071, they are the ones that put the hazmat requirement on the shipping paperwork. Bob On Sep 22, 2013, at 6:53 PM, Tom Knox act...@hotmail.com wrote: The HP and Symmetricom Cesium standards have a hazmat exemption. Thomas Knox From: li...@rtty.us Date: Sun, 22 Sep 2013 17:46:18 -0400 To: time-nuts@febo.com Subject: Re: [time-nuts] HP5061B Beam Tubes Hi Well I can answer that one. Sending a 5071 back to Symmetricom and getting a new high performance tube in it is roughly a $35K hit to the old Visa card. The hard part is getting all the shipping doc's filled out for the ultra hazardous Cs that you are shipping. You have to go to a class and get a certificate just to fill out the forms…. Perish forbid *anybody* would ever ignore those regulations and carry one on a passenger flight ……. -- Just in case you missed all the previous posts. There isn't enough Cs in a standard to harm much of anything Its so well protected that a drop off a 4 story building won't release any of it. Regardless of all that it's Hazmat. Bob On Sep 22, 2013, at 5:32 PM, Pete Lancashire p...@petelancashire.com wrote: Bob basically said it, not only 5061A but most others. I now only run my 5061A every couple months to purge it and when I want to play with my two Rb's and want them adjusted to the 5061A vs GPS. Wonder what a replacement 5071A tube runs now days ... -pete On Sun, Sep 22, 2013 at 1:36 PM, Bob Camp li...@rtty.us wrote: Hi Most of the genuine 5061 tubes out there have either died long ago or wound up in one of the ever smaller number of working 5061's. Bob On Sep 22, 2013, at 3:58 PM, W3KL w...@w3kl.com wrote: What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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 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] FE-5680A Loop Lock Indicator
I'm surprised no one suggested using two 2N's in Darlington. Then a 22K or more from the base to the indicator pin would not load things down much. Collector load then 1.2K to 2k in series with the LED. Al, K9SI ___ 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] Space mission comes to an end becuase of a computer time tagging problem
And my favorites: Nickel-Hyrdogen cells and their silvery cousins. You have to work REALLY hard to kill them. --- for rechargeable? NiCd (in the past) Lithium Ion (now) ___ 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] Space mission comes to an end becuase of a computer time tagging problem
On Sat, Sep 21, 2013 at 11:03 PM, Hal Murray hmur...@megapathdsl.net wrote: We are talking about running computers and radio gear rather than motors. I can see running motors in bursts from batteries, but computers and radios generally run continuously so they shouldn't need a battery when the sun is up. Am I missing something? Can't the computers and radios run off solar power when the batteries are dead? Does the receiver take more than (ballpark) peak solar-cell output under nasty conditions? I jst looked up some specs. The electronic is housed in a heated box. Apparently if the heat goes away some parts fail. Also it is a close call if the radio and computer could run under solar power alone. It can if the communications path uses a Mars orbiting relay but it takes 55W to transmit directly to Earth and the computer burns 15W. The computer can't run full time. It uses to much power so the solar charger has a built-in timer that can wake the computer. I looks like normal operation is to let the battery charge while the computer and everything thing else of powered down, then after so much time the charger wakes the computer so it can do something, then back to charging.This lets them do work with very degraded solar cells.But at some point the battery freeze and the heated electronics box can't be kept warm any more.This was a reasonable design for a system that had a 90 day planned operational lifetime. There are a lot of things they could have done. For example why not push the arm into the ground hard enough to left the front wheels and tilt the panels square to the sun? I guess the added weight of the more robust arm was not worth it. They had a weight, volume and cost and time budget to work with. -- 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] Space mission comes to an end becuase of a computer time tagging problem
On 9/22/13 4:48 PM, Mark Sims wrote: And my favorites: Nickel-Hyrdogen cells and their silvery cousins. You have to work REALLY hard to kill them. Yes, forgot the NiMH too.. although they self discharge --- for rechargeable? NiCd (in the past) Lithium Ion (now) ___ 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 Loop Lock Indicator
Hi Al, This is just something quick and dirty. At least it works and doesn't seem to be able to hurt anything. Bob From: Al Wolfe alw.k...@gmail.com To: time-nuts@febo.com Sent: Sunday, September 22, 2013 6:43 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator I'm surprised no one suggested using two 2N's in Darlington. Then a 22K or more from the base to the indicator pin would not load things down much. Collector load then 1.2K to 2k in series with the LED. Al, K9SI ___ 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 Loop Lock Indicator
I just did a quick inline test with the 3456A. The resistor measured just over 1000 ohms, and it's dropping just over 2.5V before it locks. So, that's about 2.5ma current draw from the FE-5680A for about 90 seconds or so. I think we're just at the splitting hairs stage on this. =) Bob From: Al Wolfe alw.k...@gmail.com To: time-nuts@febo.com Sent: Sunday, September 22, 2013 6:43 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator I'm surprised no one suggested using two 2N's in Darlington. Then a 22K or more from the base to the indicator pin would not load things down much. Collector load then 1.2K to 2k in series with the LED. Al, K9SI ___ 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 Loop Lock Indicator
Hi, A lot of indicator outputs on oscillators and other things are completely or primarily pull-downs, just like some microcontroller pins. The problem with surplus stuff like this that don't come with exact datasheets for their options is that you have to work out for yourself how it's configured, etc. If it does not look like a proper TTL or CMOS output (especially when loaded a little) it's worth checking to see if it is a pull down. Sometimes they're just weird (or faulty!). It all depends what they were designed to connect to. I find low current LEDs are useful to give some indication with minimal loading to reduce the chance of any complications, since you never know what else is going on. A while back there was some discussion of the pps output on some 5680As not working because of the lock indicator pin being pulled down too much. More info at http://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:fe5680a_faq if you have not already seen it. Angus. From: Bob Stewart To: Time Nuts Sent: September 22, 2013 10:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator I hadn't thought of using a pullup resistor. I'd have to get out the calculator to see if it's worth it, though. It's only taking a load for a minute or two till it locks, so I don't think it's a problem. Bob From: Chris Stake To: 'Discussion of precise time and frequency measurement' ; 'Bob Stewart' Sent: Sunday, September 22, 2013 2:06 PM Subject: RE: [time-nuts] FE-5680A Loop Lock Indicator I have a circuit that seems to work well: The lock indicator is a weak source but a good sink so it interfaces more naturally with a pnp or p-channel device. Pull it up to 5V with 100K and connect this point to the gate of a P channel Mosfet whose source is also connected to 5V. Connect the drain of the mosfet to a LED anode and take the LED cathode via 220 R to 0V. This way, the sense of the indicator is correct (0n = lock) and the drive capability of the lock signal works in your favour. Chris Stake -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: 22 September 2013 18:53 To: Bob Stewart; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you want 10 ma through the LED (which should be plenty) then the collector resistor would be right around 1.2K Bob On Sep 22, 2013, at 1:32 PM, Bob Stewart wrote: D'oh, that should say I could increase the COLLECTOR resistor to 1500 ohms. From: Bob Stewart To: Discussion of precise time and frequency measurement Sent: Sunday, September 22, 2013 12:27 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Except that it doesn't work with even 1500 ohms in the base lead. The LED immediately comes on and stays on. I could increase the emitter resistor to 1500 ohms and get around 8.5-9ma through the LED, but I'm done playing with it until I get a proper box to put it all in. This is just a random 3mm LED out of an HP 37203A, so maybe that has something to do with it? I haven't looked at the specs. Bob From: Bob Camp To: Discussion of precise time and frequency measurement Sent: Sunday, September 22, 2013 12:12 PM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi Circuit should be: 2N with emitter to ground, collector to LED, base to lock indicator via the 4.7K resistor. The LED is hooked to +15 via another resistor. If you have ~ 10 ma in the LED then the base needs less than 0.1 ma to do the job with a . A 4.7K should be plenty. Alternate circuit: 2N with base to lock indicator / no resistor at all, emitter to ground via a 1K resistor, collector to LED. LED to +15 via a 1.5K resistor. Either one should work. Both turn on the LED when the output is high and off when the output is low. In order to turn on when it's high you need to get an inversion ahead of the 2N. Bob On Sep 22, 2013, at 12:17 PM, Bob Stewart wrote: Hi Bob, I tried 4700 and even 1500, but they're too large. I guess the little flash of the LED at power-on is the hint that 1K is right at the ragged edge. It would probably make a big difference if there was a 100 or even 47 ohm resistor between the emitter and the LED, but my little board is starting to get burnt up, wires are starting to get frayed, and it does work, so this cake is done. Bob From: Bob Camp To: Discussion of precise time and frequency measurement Sent: Sunday, September 22, 2013 6:31 AM Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator Hi If you trace out the chip that drives the lock indicator it's got some sort of strange gating in it's supply pin. That gets
Re: [time-nuts] HP5061B Beam Tubes
Yes the Cs are long evaporated. In my frankenstein 5060/5061. I built a new oven controller to cook out the remains. It worked as the system locks and I get 2nd harmonic etc. But we are seriously speaking of fumes. It was bit of fun and it didn't really matter that I was hacking. The 5061 was a $125 flea market special. The 5060 tube was given to me from a fellow time nut and was believed dead. Well its seriously on the last fumes. I do the same thing as above. Fire it up every qtr. See that its still works, marvel that it locks and shut it down after 48 hours. Regards Paul WB8TSL On Sun, Sep 22, 2013 at 7:11 PM, Bob Camp li...@rtty.us wrote: Hi If so Symmetricom is not aware of that and neither is FedEx or UPS. When you ship in your 5071, they are the ones that put the hazmat requirement on the shipping paperwork. Bob On Sep 22, 2013, at 6:53 PM, Tom Knox act...@hotmail.com wrote: The HP and Symmetricom Cesium standards have a hazmat exemption. Thomas Knox From: li...@rtty.us Date: Sun, 22 Sep 2013 17:46:18 -0400 To: time-nuts@febo.com Subject: Re: [time-nuts] HP5061B Beam Tubes Hi Well I can answer that one. Sending a 5071 back to Symmetricom and getting a new high performance tube in it is roughly a $35K hit to the old Visa card. The hard part is getting all the shipping doc's filled out for the ultra hazardous Cs that you are shipping. You have to go to a class and get a certificate just to fill out the forms…. Perish forbid *anybody* would ever ignore those regulations and carry one on a passenger flight ……. -- Just in case you missed all the previous posts. There isn't enough Cs in a standard to harm much of anything Its so well protected that a drop off a 4 story building won't release any of it. Regardless of all that it's Hazmat. Bob On Sep 22, 2013, at 5:32 PM, Pete Lancashire p...@petelancashire.com wrote: Bob basically said it, not only 5061A but most others. I now only run my 5061A every couple months to purge it and when I want to play with my two Rb's and want them adjusted to the 5061A vs GPS. Wonder what a replacement 5071A tube runs now days ... -pete On Sun, Sep 22, 2013 at 1:36 PM, Bob Camp li...@rtty.us wrote: Hi Most of the genuine 5061 tubes out there have either died long ago or wound up in one of the ever smaller number of working 5061's. Bob On Sep 22, 2013, at 3:58 PM, W3KL w...@w3kl.com wrote: What's the story on availability of beam 5061 beam tubes? Does anyone have a supply or know of someone who does who is willing to sell one or more? I'm looking for option 004 tubes if they are available? My 5061B Option 004 is basically kaput.no beam current at all. Thanks. Jeff ___ 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 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 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] Space mission comes to an end becuase of a computer time tagging problem
No, I'm talking about nickel/gaseous hydrogen cells. Basically they can't be overcharged/overdischarged/frozen to death. State of charge can be determined by a pressure reading. Can be cycled a zillion times. -- And my favorites: Nickel-Hyrdogen cells and their silvery cousins. You have to work REALLY hard to kill them. Yes, forgot the NiMH too.. although they self discharge ___ 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.
