[time-nuts] Greetings from Australia
Hi Guys :) I thought I’d say thanks for the add to the group and introduce myself. I’m only starting to get compulsive about time and frequency. My findings so far are that only the timing of the next second matters because it’s too late to worry about the current second by the time you have the information about it. It’s +10 hours here so I have to add 10 to everything, and that could increment the date, so then a whole calendar program is required to know what the next date will be, just because you need to know what date it will be on the next seconds tick that occurs. I have a question… Is the reason most amateur radio people care about accurate frequency mostly about operating at higher radio frequencies? I imagine if a bunch of radio enthusiasts aligned their HF radios with atomic standards for use on those bands that doppler shift would ruin everything the additional hardware put into it. Cheers, Brek. ___ 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] Reeeely long term HP 5065A drift rate (13 year!)
I recently had a unit come in for repair that I had sold 13 years ago. The owner never did ANY adjustments on the unit. After the repair (which would not have affected the frequency) and before aligning the unit I decided to check and see how far it had drifted in the 13 years. Did a run against an HP 5071A and the frequency offset is 2.1X10-11th best case and 4.1X10-11th worst case. This gives an average of 1.65X10-12th to 3.15X10-12 per year! Pretty amazing! Cheers, Corby ___ 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] Splitters for the GPS antenna
The GPS splitter is spoken for. Thanks Mark Spencer Sent from my iPhone On Jun 25, 2015, at 2:07 PM, Mark Spencer m...@alignedsolutions.com wrote: Sorry for the thread hi jack. I also have a lightly used Symmetricom 58535A dual port (one antenna, two receivers) gps splitter I would be happy to part with. Please contact me off list of interested in this and perhaps we can come an agreement. It's fairly heavy so shipping may be pricey. Thanks Mark Spencer m...@alignedsolutions.com Sent from my iPhone On Jun 25, 2015, at 6:18 AM, Cash Olsen radio.kd5...@gmail.com wrote: I initially tried using Dishtv splitters with qualified success. On closer examination the bandpass between dish 1 and dish2 is different and neither actually calmed to pass the GPS frequencies. And indeed I had significantly different path losses. I wanted a better solution. I did a brief search and found the following. The results are much better and the price was very reasonable. My path losses appear to be balanced and generally agree within 1dB, with at least 10 SV reporting 39 - 49dB. The splitter I tried has a claimed bandwidth of 40 to 2400 MHz and a all ports power pass. Of course you have to have the adaptors from type N to type F and type F to type SMA. I was able to find all of those on Amazon and don't forget some type F terminators, they are hard to find in local box stores. Hope this helps some of the new guys, like myself, to get their labs up a little quicker. Computer Network Accessories, Inc. 5520 Burkhardt Road Dayton, Ohio 45431 Web: www.CNAweb.com http://www.cnaweb.com/ Email: sa...@cnaweb.com Phone: 937-258-2708 - Fax: 937-258-2743 Product NamePart No.QuantityItem PriceTotal Price4 Way 2GHz Splitter w/ DC Pass72-2443$4.10$12.30 Subtotal:$12.30Shipping Handling:$7.35Tax:$0.00 -- Order Total:$19.65 -- S. Cash Olsen KD5SSJ ARRL Technical Specialist ___ 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] Casio Watches 13 Year Drift in Seattle
But wouldn't normal watch wear just balance itself over time, one wears their watch for say 12 hours and the rest it sits on a counter at a much colder temperature. So wonder if Casio would actually go to such lengths to compensate. Maybe, interesting though. -=Bryan=- From: kb...@n1k.org Date: Sun, 28 Jun 2015 20:41:15 -0400 To: time-nuts@febo.com Subject: Re: [time-nuts] Casio Watches 13 Year Drift in Seattle Hi Just to clarify: In the “art” the watches all ran fast rather than slow. They *would* have run slow if the room temperature / skin temperature delta was an issue. Since they did not, one assumes that Casio digitally compensates this model (and probably all their watches). The typical watch tuning fork will shift more than the observed delta when run in a cold court house if un-compensated. By far the best explanation is the “set to deliberately run fast” one. Bob On Jun 27, 2015, at 8:19 PM, Jim Palfreyman jim77...@gmail.com wrote: My Casio g shock keeps extraordinary time. I did open it up and tune it, but still I'd expect it to drift. After 6 months untouched I still can't separate by eye the second from UTC. Also, with regard to the video's query about all the clocks running slow - they have been tuned to run at the temperature of a person's wrist. On Sunday, 28 June 2015, John Stuart j.w.stu...@comcast.net wrote: I think there may be a new Time-Nut in the Seattle area, , , Art, Engineering and Justice - how accurate is a Casio watch? https://www.youtube.com/watch?v=hwOMUhS8gV0 John, KM6QX ___ time-nuts mailing list -- time-nuts@febo.com javascript:; 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] Greetings from Australia
Alex, Brek - the Doppler effect is primarily an effect of the ionosphere moving. A 24 hour measurement of WWV on 20 Mhz shows as much as +/- 800 mHz movement, all due to Doppler. Note that if you run the measurement over several days at the same time of year the measured frequency will strongly correlate with time of day. This varies both with time of day and season as the height of the ionosphere varies. To a much lesser effect most of us nuts see a variation due to room temperature as this effects the frequency reference of the measurement oscillator. This effect in my shack (uncompensated) varies about +/- 1 mHz over a 20 degree (F) temperature change. 73, Michael / K7HIL On Mon, Jun 29, 2015 at 12:23 PM, Alex Pummer a...@pcscons.com wrote: Not exactly Brek, as long as the position of the two stations, which are in contact with each other, does not vary in the time, you don't have to worry about Doppler effect, also if you are trying to get in touch in SSB mode in the 13cm band, you rather have a precise frequency reference and actually the other site should have too to find each other, and where the Doppler would effect your communication a special combination of hardware-software could provide a compensation. 73 KJ6UHN Alex On 6/29/2015 9:33 AM, Brek Martin wrote: Hi Guys :) I thought I’d say thanks for the add to the group and introduce myself. I’m only starting to get compulsive about time and frequency. My findings so far are that only the timing of the next second matters because it’s too late to worry about the current second by the time you have the information about it. It’s +10 hours here so I have to add 10 to everything, and that could increment the date, so then a whole calendar program is required to know what the next date will be, just because you need to know what date it will be on the next seconds tick that occurs. I have a question… Is the reason most amateur radio people care about accurate frequency mostly about operating at higher radio frequencies? I imagine if a bunch of radio enthusiasts aligned their HF radios with atomic standards for use on those bands that doppler shift would ruin everything the additional hardware put into it. Cheers, Brek. ___ 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] Casio Watches 13 Year Drift in Seattle
Back in the day when mechanical escapement pocket watches, and wrist watches were state of the art, the jeweler would adjust the watch to run at a normal rate, and give them a daily wind. Everything looked nice in the display case. When a customer bought a watch, the jeweler would set the watch to his shop clock, and instruct the customer to wear, and wind the watch normally for two weeks, but do not set it. At the end of the two weeks, bring the watch back to the shop for a check up... When the watch came back, the jeweler would calculate the number of days the watch had been worn, note the difference from his shop clock, and calculate the daily rate of the watch. He would then set his timing machine for the the inverse of that rate, and set the watch to match. Now, when the customer wore his watch, the watch would seem to always be right on because it was adjusted for a rate that compensated for the customer's patterns of wearing the watch...his personal error. This trick had an added advantage because the customer got to see how so-so his brand new watch behaved during those two weeks, and got to be dazzled by his jeweler's rare ability to make the new watch perform so much better than the factory could! If this was normal back at the turn of the 20th century, why wouldn't Casio, and others at least do as well? Especially now that all electronic watches have a microprocessor built in... complete with temperature sensing diodes, battery monitors, and other nifty gadgets. -Chuck Harris Bryan _ wrote: But wouldn't normal watch wear just balance itself over time, one wears their watch for say 12 hours and the rest it sits on a counter at a much colder temperature. So wonder if Casio would actually go to such lengths to compensate. Maybe, interesting though. -=Bryan=- ___ 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] Greetings from Australia
Hi Brek. In my experience the perceived frequency difference from Doppler shift is of little or no relevance for amateur HF communications. For amateurs involved in activities such as the frequency measurement test I believe it could be at times relevant at HF. There might be a mode where Doppler shift is relevant for HF communications but I have never run across it. In my experience when communicating at VHF and beyond it is helpful to have an accurate frequency standard when using modes such as CW, SSB, JT65 etc. I routinely check the calibration of my 1.2 GHz (23 cm) SSB / CW setup each time I turn on the radio. I use a GPSDO as a frequency source for this. Knowing the radio is on frequency gives me one less thing to worry about when trying to make 100 mile plus contacts on this band. Even through the radio has a tcxo I still need to check the frequency each time I turn it on. From time to time I also check the calibration of my lower frequency equipment as well. The gear with TCXO's is usually close enough in frequency that I can use it on SSB and CW without having to worry about the difference between the dial frequency and the actual frequency. Radios that just have a plain crystal oscillator usually require me to figure out the difference between the dial frequency and the actual frequency when operating using SSB and CW at 144 MHz and higher. When using wider band modes such as FM on 144 and 440 MHz and narrow band modes below 30 MHz I usually trust that the dial frequency on the radio will be close enough. I hope this was of some interest. Best regards Mark S VE7AFZ Sent from my iPhone On Jun 29, 2015, at 9:33 AM, Brek Martin bmar8...@bigpond.net.au wrote: Hi Guys :) I thought I’d say thanks for the add to the group and introduce myself. I’m only starting to get compulsive about time and frequency. My findings so far are that only the timing of the next second matters because it’s too late to worry about the current second by the time you have the information about it. It’s +10 hours here so I have to add 10 to everything, and that could increment the date, so then a whole calendar program is required to know what the next date will be, just because you need to know what date it will be on the next seconds tick that occurs. I have a question… Is the reason most amateur radio people care about accurate frequency mostly about operating at higher radio frequencies? I imagine if a bunch of radio enthusiasts aligned their HF radios with atomic standards for use on those bands that doppler shift would ruin everything the additional hardware put into it. Cheers, Brek. ___ 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] Greetings from Australia
Hi On Jun 29, 2015, at 12:33 PM, Brek Martin bmar8...@bigpond.net.au wrote: Hi Guys :) I thought I’d say thanks for the add to the group and introduce myself. I’m only starting to get compulsive about time and frequency. My findings so far are that only the timing of the next second matters because it’s too late to worry about the current second by the time you have the information about it. It’s +10 hours here so I have to add 10 to everything, and that could increment the date, so then a whole calendar program is required to know what the next date will be, just because you need to know what date it will be on the next seconds tick that occurs. I have a question… Is the reason most amateur radio people care about accurate frequency mostly about operating at higher radio frequencies? I imagine if a bunch of radio enthusiasts aligned their HF radios with atomic standards for use on those bands that doppler shift would ruin everything the additional hardware put into it. Yes and no. If the ionosphere is getting involved (or other forms of propagation) then yes you will get time varying path length. The result will be a time varying phase modulation. Your frequency will always be correct. The signal “as received” will appear to be off frequency due to the phase shift caused by the path length continuously changing. Bob Cheers, Brek. ___ 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] Greetings from Australia
Not exactly Brek, as long as the position of the two stations, which are in contact with each other, does not vary in the time, you don't have to worry about Doppler effect, also if you are trying to get in touch in SSB mode in the 13cm band, you rather have a precise frequency reference and actually the other site should have too to find each other, and where the Doppler would effect your communication a special combination of hardware-software could provide a compensation. 73 KJ6UHN Alex On 6/29/2015 9:33 AM, Brek Martin wrote: Hi Guys :) I thought I’d say thanks for the add to the group and introduce myself. I’m only starting to get compulsive about time and frequency. My findings so far are that only the timing of the next second matters because it’s too late to worry about the current second by the time you have the information about it. It’s +10 hours here so I have to add 10 to everything, and that could increment the date, so then a whole calendar program is required to know what the next date will be, just because you need to know what date it will be on the next seconds tick that occurs. I have a question… Is the reason most amateur radio people care about accurate frequency mostly about operating at higher radio frequencies? I imagine if a bunch of radio enthusiasts aligned their HF radios with atomic standards for use on those bands that doppler shift would ruin everything the additional hardware put into it. Cheers, Brek. ___ 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] Large clock display from NMEA input? (Should understand leap second).
Tomorrow evening, I'm going to a leap second barbecue. The barbecue itself was the idea of a friend, but I'm bringing the equipment to show the leap second. My main setup is a Thunderbolt, Lady Heather running on a PC laptop, and a serial to USB converter. It's all working sitting here on a desk this evening, so the only thing I can't test in advance is the leap second itself. I haven't had the Thunderbolt running during a leap second before, but there is a YouTube video showing the June 2012 leap second as handled by a Thunderbolt and Lady Heather, so I'm assuming all will work as expected. Never one to trust a single piece of hardware completely, I want to bring a backup. I have an old Garmin GPS-25 board mounted in a box with power supply and RS-232 level converters, so I want to bring it too. I have watched a leap second previously on the GPS-25, so I know it handles the event properly. But the GPS-25 is NMEA output so it won't work with Lady Heather. I need something else to display a digital clock that everyone can see, from a NMEA data stream. VisualGPS displays a bunch of interesting stuff, but not time. U-center from u-blox displays UTC as both analog and digital clock, and the analog clock can be made as large as you have screen space for. Does anyone know what it does with a leap second? Are there other programs I should look at? - Dave ___ 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.
