Re: [time-nuts] Paper about DCF77 performance
> > The clock-correction seemed a bit crude. I expected to find a PI-filter > and a phase-accumulator to steer the 300 MHz to 37 MHz synthesis. Actually I do use a phase accumulator, in Fig. 26 it's inside the "binary search" block. The phase is accumulated during several seconds (longer for a noisy signal), then the binary search takes a decision in which direction to modify the clock correction. A standard binary search cannot recover from a wrong decision, therefore I use smaller steps which slowly converges to the final value. I assume that the clock correction could also be implemented with a classical PLL algorithm, it would be interesting to compare the performance. ___ 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] TimePod 5330A announcement/info (was TimePod, cross-correlation fun and measurements)
> I was recently reading the manual for the TimePod. It looks quite > nice. I'm curious as to the price. I haven't really done a formal "product announcement" on the list or anywhere else beyond the PTTI show last November, for two reasons. One is that the PTTI introduction led to a larger-than-expected amount of business... and the second, related reason is that those early adopters almost unanimously asked for some additional software features that weren't on my to-do list. I wanted to support some of those requests, such as automated test scripts and pass/fail masks, before advertising to more commercial users who would likely need the same things. Some good progress has been made in that direction, so I'm planning to raise the market visibility over the next few months. So, the short answer is that yes, the TimePod 5330A is shipping, and it's available at lead times from one to six weeks, depending on quantities ordered and parts/production scheduling at this end. The current price is US $4995.00 each for 1-5 units. > Or is this a case of "if you have > to ask, you can't afford one"? > > Joe Gray > W5JG The pricing was intended to be competitive with some of the newer time-interval counters that have been introduced with significantly fewer features and less capable specs. If someone is in the market for an Agilent 53230A or similar high-performance TIC for use at 5/10 MHz (i.e., not 1 pps), they are almost certainly better off with a TimePod instead. Other users have been manufacturers who would like to use TSC 5120A-class analyzers for production testing, but who have been deterred by the cost of putting high-end lab equipment on the factory floor. Some of the newer features being added to TimeLab are the result of requests from these users, who I didn't realize were out there at first. At the same time, quite a few R&D users are having trouble keeping their older HP 3048A gear alive, and they are looking for alternative solutions that are actively supported. For reasons too long to get into here, I tend to get a lot of email asking about HP 3048A software support, and that's really what made me decide to jump into the market in the first place. The overall idea is that while the TimePod isn't what you would call "dirt cheap," it outperforms all existing instrumentation that's available at a similar price, and it can often compete with equipment that costs 5x to 20x more. Sell sheet (from PTTI): http://www.miles.io/timepod/ss_1pg.pdf Manual: http://www.miles.io/TimePod_5330A_user_manual.pdf Software: http://www.miles.io/timelab/readme.htm (which supports a lot of other time/freq hardware besides my own) Latest beta, for more adventurous users: http://www.miles.io/timelab/beta.htm Obviously, technical discussion is more than welcome on the list, but any specific sales inquiries should go to me directly, as it's not my intent to spam the list with sales/marketing stuff beyond this post. -- john, KE5FX Miles Design LLC www.miles.io ___ 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] TimePod, cross-correlation fun and measurements
Joe wrote: I was recently reading the manual for the TimePod. It looks quite nice. I'm curious as to the price. http://www.miles.io/ Best regards, Charles ___ 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] TimePod, cross-correlation fun and measurements
Since you asked, I believe the TimePod is around $5000. An excellent value for anyone serious about time and freq. I was lucky enough to meet John recently at the NIST Time and Freq Seminar and he is a very approachable you should give him a call if you are interested. Thomas Knox 1-303-554-0307 > Date: Sun, 17 Jun 2012 20:32:04 -0600 > From: jg...@zianet.com > To: time-nuts@febo.com > Subject: Re: [time-nuts] TimePod, cross-correlation fun and measurements > > > I also picked up my TimePod out of the hands of no other than John Miles > > himself. > > I was recently reading the manual for the TimePod. It looks quite > nice. I'm curious as to the price. Or is this a case of "if you have > to ask, you can't afford one"? > > Joe Gray > W5JG > > ___ > 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] TimePod, cross-correlation fun and measurements
On Jun 17, 2012, at 9:32 PM, Joseph Gray wrote: > I was recently reading the manual for the TimePod. It looks quite > nice. I'm curious as to the price. Or is this a case of "if you have > to ask, you can't afford one"? The price is right on the TimePod web site: http://www.miles.io. I couldn't be happier with the TimePod that I got back in December. Highly recommended. Kevin ___ 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] TimePod, cross-correlation fun and measurements
> I also picked up my TimePod out of the hands of no other than John Miles > himself. I was recently reading the manual for the TimePod. It looks quite nice. I'm curious as to the price. Or is this a case of "if you have to ask, you can't afford one"? Joe Gray W5JG ___ 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] Paper about DCF77 performance
On 6/17/2012 5:18 PM, Daniel Engeler wrote: Here is the PDF version of my paper "Performance Analysis and Receiver Architectures of DCF77 Radio-Controlled Clocks", which was published in the May 2012 issue of the IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control: http://goo.gl/sWjFX Have fun reading! I'd be glad to hear your feedback. --Daniel Engeler ___ 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. Thanks looking forward to reading it. Paul WB8TSL ___ 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] Paper about DCF77 performance
Hi Daniel, On 17/06/12 23:18, Daniel Engeler wrote: Here is the PDF version of my paper "Performance Analysis and Receiver Architectures of DCF77 Radio-Controlled Clocks", which was published in the May 2012 issue of the IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control: http://goo.gl/sWjFX Have fun reading! I'd be glad to hear your feedback. First of all, many thanks for providing us with a link to the paper. Second, it's a good paper. It includes the inherent re-occurence of the signal which can be utilized. Good to see that. There is many layers of analysis, so one has to be patient when reading this to see it through. I was lacking a frequency/time stability measurement. It would have been good to know how good it is in time stability. TIE, ADEV and TDEV plots would have been welcome. Possibly even an MTIE. Also, I would have enjoyed a stability analysis for code and carrier phase separately. 24h plot of them shifting around with a GPS receiver as reference would suffice. The clock-correction seemed a bit crude. I expected to find a PI-filter and a phase-accumulator to steer the 300 MHz to 37 MHz synthesis. 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] TimePod, cross-correlation fun and measurements
Fellow time-nuts, As you know, I spent last week in Boulder. NIST T&F seminar, fellow time-nuts and much fun. I also picked up my TimePod out of the hands of no other than John Miles himself. Being sleep deprived from the travel, progress have been slow, but I have now come to the point where I got a bunch of measurements done. This has been greatly aided by the excellent cables and adapters provided by Tom Knox. I did a comparison of my OSA8601-02 SN1314 and OSA8600-1 SN817. Some material to let you know what these are, see: http://rubidium.dyndns.org/~magnus/time/oscilloquartz/8601/ Essentially the 8601 is a different interconnection mounting than the 8600. I tend to refer to them as 8600s as they are essentially the same. However, my 8601 is an older generation than my 8600. We will come back to that. I have made three essential measurements: OSA8600-OSA8601 pair (one as input and one as reference) OSA8601 with dual reference (OSA8600 and HP5065A) OSA8600 with dual reference (OSA8601 and HP5065A) With the first measurement, I get the sum of the noise-levels. With the second and third, the noise of the other sources cross-correlates out to some degree and the individuals noise should remain. It works to some degree. Let's see how the noise-floor measurements look: http://rubidium.dyndns.org/~magnus/time/timelab/OSA8600_HP5065A_OSA8600_20120618_1.png The green trace is the sum of them both. This is best seen from 10 Hz and above. The blue trace is the OSA8601-02 AT-cut BVA. The purple trace is the OSA8600-1 AT cut BVA. The overall plot shows the typical f^-3 noise, some f^-1 noise and the white noise. The white noise is around -155 dBc or better and is essentially flat from 1 kHz to 100 kHz, except for the 20 kHz bump. This bump I do not know the source of. In the 7 Hz to 500 Hz region, the f^-1 noise of the 8600 dominates the sum (green), where as below 7 Hz the 8601 f^-3 noise dominates. Considering that their Q values should be roughly the same, and hence their break-point, it is fair to assume that the white noise of the 8600 buffer amp is worse than the 8601 buffer amp, but the amplifier core of the 8600 is better than the 8601 amplifier core. Doing a Hadamard analysis with linear drift: http://rubidium.dyndns.org/~magnus/time/timelab/OSA8600_HP5065A_OSA8600_20120618_2.png and without linear drift: http://rubidium.dyndns.org/~magnus/time/timelab/OSA8600_HP5065A_OSA8600_20120618_6.png Shows kind of OK values, with the flat part of ADEV around 3-5 E-13. It's obvious how the 50 Hz breaks through, and that spurious was clearly visible in the phase-noise plots too. To maintain that low I kept lights off in the lab (with me walking around the disaster area with few visual cueues). Obviously I need to work on that. The ADEV is clearly school-book with a 9E-14/tau slope and then level out at about 4E-13 and then go steep up at tau or tau square depending on the linear drift being removed or not. This prooves that the frequency drift is not linear, and that Hadamard is not able to remove the effect. Looking at the phase difference: http://rubidium.dyndns.org/~magnus/time/timelab/OSA8600_HP5065A_OSA8600_20120618_3.png and frequency difference: http://rubidium.dyndns.org/~magnus/time/timelab/OSA8600_HP5065A_OSA8600_20120618_4.png Reveal that this is not matching up very well with the linear drift assumption, but there is clearly a systematic effect in here. A better frequency drift model should be applied, and it can be assumed that it pollutes the xDEV data, especially in the long-term. Finally a look at TDEV http://rubidium.dyndns.org/~magnus/time/timelab/OSA8600_HP5065A_OSA8600_20120618_5.png For short times, the time-stability can be as low as below 20 fs RMS. It is clear that 50 Hz noise is a threat for that performance. At 1 s they all remain below 300 fs. 1 ns stability is in the range of 100-400 s or so. Actually, there is many improvements in how these measures are being done, but it is a nice example of how cross correlation allows one to measure below onces oscillators noise. The HP5065A is even noiser. I could for instance not trim the OSA8601 for optimum frequency, so the measurements of the OSA8600 may suffer from tracking issues. This could be the explanation that the f^-3 noises isn't as good as they should be. Also, the OSA8600s wasn't separated physically or power-wise. It's pretty good numbers in there. -121.9 dBc and -147 dBc for 1 and 10 Hz is pretty amazing numbers, for a home lab. Suggestions for improvements is welcome. The long measurements was for 1 hour. Now, nobody donating a H-maser or two? 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] Paper about DCF77 performance
Hi Very interesting !!! Thanks very much for sharing it. Bob On Jun 17, 2012, at 5:18 PM, Daniel Engeler wrote: > Here is the PDF version of my paper "Performance Analysis and Receiver > Architectures of DCF77 Radio-Controlled Clocks", which was published in the > May 2012 issue of the IEEE Transactions on Ultrasonics, Ferroelectrics, and > Frequency Control: > > http://goo.gl/sWjFX > > Have fun reading! I'd be glad to hear your feedback. > > --Daniel Engeler > ___ > 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] Paper about DCF77 performance
Here is the PDF version of my paper "Performance Analysis and Receiver Architectures of DCF77 Radio-Controlled Clocks", which was published in the May 2012 issue of the IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control: http://goo.gl/sWjFX Have fun reading! I'd be glad to hear your feedback. --Daniel Engeler ___ 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] Paper about DCF77 performance
Hm. Is the paper now online or do I have to add it to my list of downloads at next university trip? Thanks - Henry Hal Murray schrieb: enge...@alumni.ethz.ch said: Building the best DCF77 receiver in the world :-) You have found the right place. :) -- ehydra.dyndns.info ___ 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] HP5386A GPIB
Hui, The older instruments have a very simple command structure. You don't need the "?" to query. Typically just doing a GPIB Read command (ibread for NI controllers) will address the counter to output and it will send the current reading. This can cause a problem if you request data too soon after a setup command. You'll get the previous reading. The "ENTER S ; N$" command just reads from address "S" into the variable "N$". It sound like you need the command to your USB-GPIB controller to get it to read. The counter is probably ready to send the data, the controller just needs to initiate its read cycle. Mike On 6/17/2012 10:17 AM, Hui Zhang wrote: I have a old HP5386A counter and a OEM USB-GPIB controller(no tech support), I use a serial port debug program to send command via USB-GPIB to HP5386A, when I send "FU2"(Measure period) or "DI"(increment display digis), the 5386 response the command and worked well, the other control command in the HP's manual also worked well. But I don't know how to read the measure value from 5385A, in my HP3478A mutilmeter case, I just send a "?", it will return voltage value to software, but at 5386A, the “?” not work, I got error message "52" on LCD panel. I read the HP5386's manual, the demonstrates used "ENTER" command to get measure value, but the "ENTER" is a HP-BASIC command of vintage HP-85 computer. I don't know how to send similar command to control my counter, can someone give me some advice? Thank you! Hui ___ 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] HP5386A GPIB
I have a old HP5386A counter and a OEM USB-GPIB controller(no tech support), I use a serial port debug program to send command via USB-GPIB to HP5386A, when I send "FU2"(Measure period) or "DI"(increment display digis), the 5386 response the command and worked well, the other control command in the HP's manual also worked well. But I don't know how to read the measure value from 5385A, in my HP3478A mutilmeter case, I just send a "?", it will return voltage value to software, but at 5386A, the “?” not work, I got error message "52" on LCD panel. I read the HP5386's manual, the demonstrates used "ENTER" command to get measure value, but the "ENTER" is a HP-BASIC command of vintage HP-85 computer. I don't know how to send similar command to control my counter, can someone give me some advice? Thank you! Hui ___ 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.
