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

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’ [4]. The LC_XO is available as TCXO or more stable OCXO version. *It is ele

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,

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

Re: [time-nuts] Reflections and Low Phase Noise

I have heard it called about everything up to a 1000 year flood. But I also heard a University of Colorado professor who monitors Boulder creek called it a twenty five year flood. In any case I was lucky. Thanks; Thomas Knox > To: time-nuts@febo.com > From: hmur...@megapathdsl.net > Date: Sat,

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 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 batter

Re: [time-nuts] FE-5680A Loop Lock Indicator

b...@evoria.net said: > Is 3ma really that big a deal?  I know squat about CMOS gates.  I guess it > is pulling the voltage down by 25%, though. There should be something in the data sheet. 1/2 :) If you trace the signal back the next time you have it open, you might be able to figure out whi

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

On 9/21/13 6:40 PM, Hal Murray wrote: jim...@earthlink.net said: If it gets cold enough (without power from solar cells, it won't generate enough internal heat to keep warm), it will die. That's probably what happened to Spirit on Mars. It got cold enough during the Martian winter, and with

Re: [time-nuts] Space mission comes to an end because of a "computer time tagging" problem

jim...@earthlink.net said: > Then on the ground, we time tag (with an atomic clock) when the telemetry > frame is received. (giving you "Earth Received Time" or ERT) Someone on the > ground does a process of time correlation figuring out what spacecraft time > corresponds to what TAI time, allow

Re: [time-nuts] FE-5680A Loop Lock Indicator

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

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 >To: Time Nu

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

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

jim...@earthlink.net said: > If it gets cold enough (without power from solar cells, it won't generate > enough internal heat to keep warm), it will die. That's probably what > happened to Spirit on Mars. It got cold enough during the Martian winter, > and with not enough solar power, enough t

Re: [time-nuts] Reflections and Low Phase Noise

Looks like Colorado's version of a hurricane. I'm pretty much convinced that, no matter what you have or where you live, Mother Nature can pretty much take it all away from you without much warning using wind, fire, water, and/or earth quake. Life is about the journey, not the destination. All w

Re: [time-nuts] Reflections and Low Phase Noise

> 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.

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" Sent: Saturd

[time-nuts] HP 5061A Problem

Adrian, You can use either Zeeman frequency as long as you use the corresponding A1 frequency synthesizer setting. See: http://www.febo.com/pipermail/time-nuts/2005-April/018171.html This does not matter for troubleshooting but once you want to get "on frequency" they need to match. Corby

Re: [time-nuts] Reflections and Low Phase Noise

Tom, Don't forget the 'stand-by' generator to keep that pump running. If you have natural gas and can 'plant' a propane tank in the ground, you can get an automatic transfer, dual fuel, generator with an automatic transfer switch to power the entire house and automatically put the generator and t

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

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 wrote: > Hi Bob, > > It's rather curious. Using my handheld DVM in the diode scale, I get a > reading of 448 in one direc

Re: [time-nuts] FE-5680A Loop Lock Indicator

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

Re: [time-nuts] Reflections and Low Phase Noise

Hi, On 09/21/2013 07:50 PM, Tom Knox wrote: > If this at first appears to be off topic read on. > Having this year survived fire evacuations and most recently what has been > called anything from a five to 1000 year flood here in Boulder, I have has a > little time to reflect on just how lucky I

Re: [time-nuts] New NTBW50AA

I did a bit of sleuthing today about my dBc numbers. Looks like my best numbers happened (47.2 and 44.7) when the antenna was on the shortest piece of feed line, maybe 30', right above my room but well under the canopy of trees. Highest dBc I get now is in the low 40's with 150' of feed and t

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 wrote: > The instructions I got with this Rb said that you could h

Re: [time-nuts] HP 5061A Problem

Corby, many thanks for the comprehensive instructions. After the harmonic generator alignment I measured 90mV into the 10Meg DMM input, so the beam current should be 9nA. The floor with the harmonic generator pot fully ccw was 6nA. I didn't change the generator output during the LF test. To g

Re: [time-nuts] Reflections and Low Phase Noise

Tom: I would like to see that paper. Thanks, jim wb4...@amsat.org On 9/21/2013 1:50 PM, Tom Knox wrote: If this at first appears to be off topic read on. Having this year survived fire evacuations and most recently what has been called anything from a five to 1000 year flood here in Boulder, I

Re: [time-nuts] HP 5061A Problem

If you have another reference like a GPS or Rubidium it makes set up much easier since you simply tune to 5MHz and then adjust current. The High Perf Tubes often needed to be degaussed, I have the 10638A but no cable if that is any help contact me off list. Also placing an external power supply

[time-nuts] Reflections and Low Phase Noise

If this at first appears to be off topic read on. Having this year survived fire evacuations and most recently what has been called anything from a five to 1000 year flood here in Boulder, I have has a little time to reflect on just how lucky I was. Over the last few years I have made a few upgr

Re: [time-nuts] New NTBW50AA

R is to read files. I tried all 3 reset (!) commands, warm, cold and hard. (and said 'OH no what have I done) Warm locked in about 3 minutes and cleared the holdover, cold locked in 10 minutes, hard locked in 10 minutes but cleared the lat lon, reset the EL to 10, AMU to 4. I put the lat lon a

Re: [time-nuts] FE-5680A Loop Lock Indicator

There is a problem introduced if you sink too much current off the lock pin. An LED draws enough current to cause the issue, I think to do with not going into lock or PPS output. If I could just remember what the issue is... Anyway, this guy has it nailed: http://www.ka7oei.com/10_MHz_Rubidium_

Re: [time-nuts] FE-5680A Loop Lock Indicator

If the lock output comes from the micro or a logic port with a maximum output of 3.3 or 5V, a LED connected to it from +15 will be always ON. On Sat, Sep 21, 2013 at 4:55 PM, Bob Stewart wrote: > The instructions I got with this Rb said that you could hook an LED through a > 5-10K resistor to th

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

from JPL http://www.jpl.nasa.gov/news/news.php?release=2013-275 "Mission controllers postulate that there was an anomaly generated by the spacecraft's software which left the vehicle's computers in a condition where they are continuously rebooting themselves. If this is the case, the computers wo

Re: [time-nuts] FE-5680A Loop Lock Indicator

Hi John, Thanks for the response.  I don't think my unit is the same as that one.  The instructions I got did not mention any +5V.  Also, this is not a 10MHz unit, it is only a timing unit.  The internal frequency is 8.38860798/9 (last digit jitter) MHz. Bob >_

Re: [time-nuts] FE-5680A Loop Lock Indicator

Are you applying +5V to pin as well? See: http://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:fe5680a_faq "Within 5 minutes after powering up (apply +15V on DB9 pin 1 and +5V on pin 4) the unit should indicate lock (pin 3 voltage drops low)." John WA4WDL --

Re: [time-nuts] Doppler and FMT

On 09/20/2013 04:34 AM, quartz55 wrote: > But when working with clocks (time, frequency, stability measurements) this > assumption often not true and it's helpful to think of averaging more as a > disease than a cure. > > /tvb > > I can understand that. > > Dave >

[time-nuts] HP 5061A Problem

Adrian, Most used High stability tubes are DOA but you might get lucky! You say the low frequency test "worked". What was the amplitude of the peak in nanoamps and was the peak well above the noise or baseline level? Once you were on the peak did you adjust the 41.6Khz amplitude to max the sign

[time-nuts] FE-5680A Loop Lock Indicator

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 op

Re: [time-nuts] HP 5061A Problem

Adrian It looks like you are gathering a lot of good detail. I have a couple of thoughts. But will say there are many on this list that are far far more knowledgeable then me. My experience was in building a hp 5060/61 combo. A mixed marriage that worked. That said. You don't mention the current re

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

On 09/21/2013 03:26 PM, Jim Lux wrote: > On 9/21/13 6:03 AM, Magnus Danielson wrote: >> On 09/21/2013 02:52 PM, Bob Camp wrote: >>> Hi >>> >>> So it's a pretty good AT cut crystal without any compensation of >>> heating. Not quite a cheap wrist watch, but not a BVA in a dewar >>> flask either. >> T

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

On 9/21/13 6:03 AM, Magnus Danielson wrote: On 09/21/2013 02:52 PM, Bob Camp wrote: Hi So it's a pretty good AT cut crystal without any compensation of heating. Not quite a cheap wrist watch, but not a BVA in a dewar flask either. The environmental perturbations should go quite slow most of t

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

On 9/21/13 5:52 AM, Bob Camp wrote: Hi So it's a pretty good AT cut crystal without any compensation of heating. Not quite a cheap wrist watch, but not a BVA in a dewar flask either. Yep. The AuxOsc is what is used if you don't want to have the downlink locked to the uplink.

Re: [time-nuts] Space mission comes to an end because of a "computer time tagging" problem

On 9/21/13 5:41 AM, Bob Camp wrote: Hi I'd be a bit surprised if they were running anything as power hungry as an Rb all the time when a quartz based device would be smaller / lower power / lower volume. Of course they may have had mission requirements that drive them to a hydrogen maser ...

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

On 09/21/2013 02:52 PM, Bob Camp wrote: > Hi > > So it's a pretty good AT cut crystal without any compensation of heating. Not > quite a cheap wrist watch, but not a BVA in a dewar flask either. The environmental perturbations should go quite slow most of the time, as it glides in the void slowly

[time-nuts] HP 5061A Problem

I got a 5061A with high performance tube that I'm trying to get running. The Cs oven works and the -3500 and -2500V are there. The beam current has its maximum at the correct frequency. 90MHz from the multiplier are there and they are phase modulated with 137Hz at about 0.01 rad. Measured on a

Re: [time-nuts] Space mission comes to an end because of a "computer time tagging" problem

Jim, On 09/21/2013 01:32 PM, Jim Lux wrote: > On 9/21/13 2:30 AM, Rob Kimberley wrote: >> David, >> >> The satellite has probably got a Rb as its clock (hopefully more than >> one). > > Very, very few deep space probes carry a Rb ( I can't think of any off > hand). Regular old quartz, usually som

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

Hi So it's a pretty good AT cut crystal without any compensation of heating. Not quite a cheap wrist watch, but not a BVA in a dewar flask either. Bob On Sep 21, 2013, at 8:11 AM, Jim Lux wrote: > from JPL > http://www.jpl.nasa.gov/news/news.php?release=2013-275 > > "Mission controllers post

Re: [time-nuts] Space mission comes to an end because of a "computer time tagging" problem

Hi I'd be a bit surprised if they were running anything as power hungry as an Rb all the time when a quartz based device would be smaller / lower power / lower volume. Of course they may have had mission requirements that drive them to a hydrogen maser ... Bob On Sep 21, 2013, at 5:30 AM, Rob

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

from JPL http://www.jpl.nasa.gov/news/news.php?release=2013-275 "Mission controllers postulate that there was an anomaly generated by the spacecraft's software which left the vehicle's computers in a condition where they are continuously rebooting themselves. If this is the case, the computers

Re: [time-nuts] Space mission comes to an end becuase of a "computer time tagging" problem

On 9/20/13 5:12 PM, Bob Camp wrote: Hi Low bid wrist watch used as time base? - I'd bet there is some form of master time tick in their RTOS that keeps everything pumping. Loose the time tick (or the time tick count) and it all goes away… yes and no. Most spa

Re: [time-nuts] Space mission comes to an end because of a "computer time tagging" problem

On 9/21/13 2:30 AM, Rob Kimberley wrote: David, The satellite has probably got a Rb as its clock (hopefully more than one). Very, very few deep space probes carry a Rb ( I can't think of any off hand). Regular old quartz, usually some sort of tcxo. If they are doing radio science, then it

Re: [time-nuts] Low Phase Noise Ref?

Tom, On 09/20/2013 06:37 PM, Tom Knox wrote: > We all have our idea of what a low or Ultra Low phase noise oscillator > is. For 5 and 10MHz references I usually look first at 1Hz offset then > the noise floor. At 5MHz I consider 125dB @ 1Hz state of the art. But > now with work by Archita Hati and

Re: [time-nuts] Space mission comes to an end because of a " computer time tagging" problem

If I was to make an educated guess about this one I'd say that it is more likely to be an overflow problem. The spacecraft was operating for significantly longer than it's builders or programmers ever considered likely. -Geoff. On Sat, 21 Sep 2013 07:30:54 pm Rob Kimberley wrote: > David, > >

Re: [time-nuts] Space mission comes to an end because of a "computer time tagging" problem

David, The satellite has probably got a Rb as its clock (hopefully more than one). All I can imagine is that there has been a major clock failure of some sort, and everything is in free run and unable to sync up with ground. Thoughts? Rob -Original Message- From: time-nuts-boun...@febo.