Re: [time-nuts] Down under Time Nuts Tsunami's
jim77...@gmail.com said: I always use 09:44 (UT+11) to remove all ambiguity. Well, by the time your message got there, it said: Date: Thu, 8 Oct 2009 12:52:02 +1100 What was it when it left your end? -- These are my opinions, not necessarily my employer's. 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] Any Time nuts in AU?
Hi all, Another one here in Melbourne :-) Morris VK3DOC From: Nic McLean mcle...@bigpond.com Subject: Re: [time-nuts] Any Time nuts in AU? Yes Ray there are quite a few of us! Nic VK2KXN / VK5ZAT Sydney / Adelaide Hills; Australia. Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. ___ 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] Any Time nuts in AU?
I'm not in AU (left coast US), but I've got a clock on my office wall that runs backwards (the numerals progress CC too). I think I got it as a gift years ago when Dick Smith had a store in the area. It didn't last very long. Cheers, -Dave - Original Message - From: Joseph Gray jg...@zianet.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, October 7, 2009 3:14:14 AM GMT -07:00 US/Canada Mountain Subject: Re: [time-nuts] Any Time nuts in AU? Does time run backwards down there? :-) Joe Gray KA5ZEC On Wed, Oct 7, 2009 at 2:53 AM, Ray Hudson hudson...@yahoo.com.au wrote: Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Any Time nuts in AU?
Good day all I am a mountaineer in the Blue Mountains, west of Sydney. I don't worry much about any extra digit (up to now), happy with whatever I have, heard and learn from America, Europe and down here Oceania from time nuts mail tunnel, those info are always above my head and very informative. How do I keep time ? I built several GPSDOs from scratch since 2006 with NavSync CW25 - TIM module, with 1PPS and NCO up to 30.000MHz. I have only one clock, an FRK,uncalibrated, as I learn from the group, a man with one clock is a happy man ! I do not have any HP timing related test gear, I use a soundcard stereo input for comparison, still waiting for any instruction from the group how to clock the PC up to nuts-standard. Cheers from Pascal VK2IHL / XV2PN On Thu, Oct 8, 2009 at 9:11 AM, arie schellaars arie.schella...@yahoo.com wrote: G'day folks. I am Latrobe Valley Victoria. Cheers Arie VK3DBF Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Any Time nuts in AU?
And there's another timenut in Melbourne. Regards to all. Max Skop VK3YBA On Wed, Oct 7, 2009 at 7:53 PM, Ray Hudson hudson...@yahoo.com.au wrote: Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Any Time nuts in AU?
Hell, Yes, we get all the days fresh and new in the Mainland before we flog them off to the West Island. Those poor diggers always get the hand-me-downs :-) Cheers, Steve Rooke 2009/10/8 Neville Michie namic...@gmail.com: Hi, I am in Sydney where I am playing at setting up time standards and making precision mechanical clocks. We get to use all the days just after the NZ people have used them. Then we send them on to Asia, Europe then UK who send them on to USA when they are almost worn out. cheers, Neville Michie On 07/10/2009, at 7:53 PM, Ray Hudson wrote: Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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. -- Steve Rooke - ZL3TUV G8KVD A man with one clock knows what time it is; A man with two clocks is never quite sure. ___ 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] Any Time nuts in AU?
Hi Ray, Another Melbourne nut and long time follower of this list. A couple of years ago I got snipped bidding on an ex RAAF HP cesium frequency standard. It was very sad to see someone in the states paying $800+ to ship the unit back to the US... Does anyone know what happened to the ex TRL equipment? And more recently the gear from Telstra's CDMA network? Cheers, - Mark 2009/10/7 Ray Hudson hudson...@yahoo.com.au: Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Any Time nuts in AU?
Mark, i've seen some of (i'm guessing) ex Telsrta gear going through The Macservice Group (TMG) and through Oatley electronics. But I'd love to know where the rest of it goes as well. Ray. --- On Thu, 8/10/09, Mark Treacy mark.tre...@gmail.com wrote: From: Mark Treacy mark.tre...@gmail.com Subject: Re: [time-nuts] Any Time nuts in AU? To: Discussion of precise time and frequency measurement time-nuts@febo.com Received: Thursday, 8 October, 2009, 9:52 PM Hi Ray, Another Melbourne nut and long time follower of this list. A couple of years ago I got snipped bidding on an ex RAAF HP cesium frequency standard. It was very sad to see someone in the states paying $800+ to ship the unit back to the US... Does anyone know what happened to the ex TRL equipment? And more recently the gear from Telstra's CDMA network? Cheers, - Mark 2009/10/7 Ray Hudson hudson...@yahoo.com.au: Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] HP 5315A info?
Can someone tell me if there is a repository or a web site with all the info on modifing a HP5315 for external reference. And I suppose all the other project time nuts do. Thanks Ray VK4TFT Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Any Time nuts in AU?
The rest is at home in the sheds of ex Telstra employees Horst Schmidt Ray Hudson wrote: Mark, i've seen some of (i'm guessing) ex Telsrta gear going through The Macservice Group (TMG) and through Oatley electronics. But I'd love to know where the rest of it goes as well. Ray. --- On Thu, 8/10/09, Mark Treacy mark.tre...@gmail.com wrote: From: Mark Treacy mark.tre...@gmail.com Subject: Re: [time-nuts] Any Time nuts in AU? To: Discussion of precise time and frequency measurement time-nuts@febo.com Received: Thursday, 8 October, 2009, 9:52 PM Hi Ray, Another Melbourne nut and long time follower of this list. A couple of years ago I got snipped bidding on an ex RAAF HP cesium frequency standard. It was very sad to see someone in the states paying $800+ to ship the unit back to the US... Does anyone know what happened to the ex TRL equipment? And more recently the gear from Telstra's CDMA network? Cheers, - Mark 2009/10/7 Ray Hudson hudson...@yahoo.com.au: Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Down under Time Nuts
- Original Message - From: Magnus Danielson mag...@rubidium.dyndns.org Some of you actuallly work in the field I gather. :) snip- Some of us work in it- but most of us just play there. If you play hard enough, sometimes you get paid... DaveB, NZ ___ 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] Tbolt instability
Tbolts seem to have a very good reputation for accuracy and stability. Most comments I have seen compare them favorably to the HP/Symmetricom Z3801. Mine may be OK in the very long term but doesn't look too good in the short term. Let me explain. First, I'll describe my set up. I have a Z3801 which has been running continously for at least 6 weeks. The 10 MHz output feeds a resistive 2 way splitter with one output going to the external timebase input of a Racal Dana 1992. The other goes to input B of said 1992. The 10 MHz output of the Tbolt goes to input A. What I am seeing, this is after a 20,000 point self survey and being powered on overnight, is that the time difference between the Tbolt and Z3801 varies by as much as 10 nS over a period of a couple of minutes. Sometimes, it moves 4 or 5 nS in a few seconds. I don't believe this is either the 1992 or Z3801 because when I connect the Z3801 to A and B through different length cables, I see a constant, non changing time difference. I also don't believe it is the Z3801 because I have compared several TCXOs and one Rubidium to it in the past few weeks. Without exception, the time difference moved, either up or down, in a constant fashion. In the case of the Rubidium, it would slip a nS in just under an hour. This was always constant and in the same direction with an occasional dither of 1 nS. I can't believe this is normal. I would assume that two GPS receivers fed from the same antenna would see the same satellites and if they had an error, it would be the same error so no difference in timing between the two signals. It seems to me that the way the two receivers discipline their respective oscillators is responsible. The Tbolt adjusts quickly, while the Z3801 adjusts very slowly. Lady Heather is currently showing an ADEV of 1.5 x 10-11. This doesn't seem all that good to me considering that the receiver has been on for 16 hours. Shoud I give it a couple of days and try again? I had plans to use the Tbolt instead of the Z3801 as a cal standard here at work but I am now inclined to use the LPRO and cal it against the Z3801 maybe twice a year. Is there a way I can improve the Tbolt? Sorry for the lengthy post but I felt I should explain everything as completely as possible. ___ 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] Tbolt instability
I think I might have found at least part of the answer. Extreme sensitivity to ambient temperature. I held a heat gun a couple of feet away and in under a minute, it went nuts. I don't think I was heating the OCXO that much. I believe it was the internal temperature sensor. I didn't get it that hot, maybe 90 degrees F or so. It seems to me that it would have been better for them to try to sense the internal temperature of the OCXO somehow rather than ambient if that was the aim of installing a sensor to start with. If it is the internal sensor, then going to an externally mounted, much better thermally insulated OCXO wouldn't help. I know some have retrofitted Tbolts. Did it cure the temperature sensitivity? ___ 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] Tbolt instability
How large a self survey did you take with the TB? The default survey size is relatively small. If you increase the size of the self survey to be (say) 24 hours of data (24*60*60 = 86400) you may find you get a much better self survey position which should result in better stability (based on Mark Sims' recent research). Mark will soon be releasing a new version of Lady Heather that will collect position readings over 48 hours and then do some fancy stats on this data to set the position accurately. Side question to Mark: Any thoughts on release dates? I'm not sure how long the TB needs to be on to reach a stable state, but do know that it suffers from a heisenberg problem in that the temperature as reported by the onboard sensor chip starts to climb quite fast if you start monitoring the TB using the serial port. I'm sure the Z3801 will be more stable, as IIRC it uses a very long time constant for disciplining the 10811A. I suspect that if you had an accurate source like a maser to check against, you could come up with a better time constant and damping factor for the TBolt than the factory default settings, and this would allow it to give much better results, but what do I know? I only have one clock that's reasonably trustworthy (the TB), so I'm happy - I'm sure if I had more I would start to worry ... Dave -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of John Green Sent: 08 October 2009 14:51 To: time-nuts@febo.com Subject: [time-nuts] Tbolt instability Tbolts seem to have a very good reputation for accuracy and stability. Most comments I have seen compare them favorably to the HP/Symmetricom Z3801. Mine may be OK in the very long term but doesn't look too good in the short term. snip ___ 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] Any Time nuts in AU?
I just can't resist this one. As an undergrad at a very well known eastern US engineering school, we liked hacks. Also, we hardware types looked down on the theory guys with some distain. Anyway, a friend of mine's roommate was a hair grinder... he had very high grades, but was clueless about hardware. In those days, almost everyone had those little GE line powered clocks with a synchronous motor. One Christmas vacation, he left school for a week or so. We took his clock apart and flipped the magnet structure so the shading pole was on the other side, so the thing ran backwards. He came back, and was mystified. We said nothing. He pulled several books down from the shelf and mumbled a while, then said Oh. He then unplugged the clock from the wall, got a pair of scissors, and cut the line cord, spliced it back together w/ masking tape with the leads reversed, and plugged it in again. Of course it STILL ran backwards. We were all on the floor laughing uncontrollably. We did ask him why he'd simply not flipped the plug in the socket and he said Oh, that wouldn't have worked. True story. Honest. BTW, we eventually bought him a new clock for about $3. Names withheld to protect the clueless. Last I heard he was running a government agency. -John === I'm not in AU (left coast US), but I've got a clock on my office wall that runs backwards (the numerals progress CC too). I think I got it as a gift years ago when Dick Smith had a store in the area. It didn't last very long. Cheers, -Dave - Original Message - From: Joseph Gray jg...@zianet.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, October 7, 2009 3:14:14 AM GMT -07:00 US/Canada Mountain Subject: Re: [time-nuts] Any Time nuts in AU? Does time run backwards down there? :-) Joe Gray KA5ZEC On Wed, Oct 7, 2009 at 2:53 AM, Ray Hudson hudson...@yahoo.com.au wrote: Just a test to see if I can send to the mailing list and to find out how many time nuts are in the land down under Thanks Ray. Send instant messages to your online friends http://au.messenger.yahoo.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Time Running Backwards
I have a Goofy (Disney) watch, where the hands run backwards. This was actually not uncommon in barber shop clocks, when looked at in the mirror they are correct. Ralph On Oct 8, 2009, at 3:07 AM, d.sei...@comcast.net wrote: I'm not in AU (left coast US), but I've got a clock on my office wall that runs backwards (the numerals progress CC too). I think I got it as a gift years ago when Dick Smith had a store in the area. It didn't last very long. Cheers, -Dave - Original Message - From: Joseph Gray jg...@zianet.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, October 7, 2009 3:14:14 AM GMT -07:00 US/Canada Mountain Subject: Re: [time-nuts] Any Time nuts in AU? Does time run backwards down there? :-) Joe Gray KA5ZEC ___ 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] Tbolt instability
A lot depends upon the temperature sensor in the Tbolt. Dallas Semi changed the guts of the sensor ship in such a way that the Tbolt can only get 1 degree resolution out of it. Later production Tbolts all have that sensor. Does your Tbolt show a mostly flat line temp curve with coarse, step-like transitions or one that tracks the temperature rather finely? When you hit the thing with the hot air, what did the temperature plot do? Also, the temperature sensor would do no good inside the OCXO (there is already one in there). The Tbolt temperature sensor is used to compensate the unit for temperature effects on the unit as a complete system. It is also used for environmental alarms, etc. _ Hotmail: Powerful Free email with security by Microsoft. http://clk.atdmt.com/GBL/go/171222986/direct/01/ ___ 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] Tbolt instability
Tbolts seem to have a very good reputation for accuracy and stability. Most comments I have seen compare them favorably to the HP/Symmetricom Z3801. Mine may be OK in the very long term but doesn't look too good in the short term. Let me explain. First, I'll describe my set up. I have a Z3801 which If this was a TAPR unit, send me the S/N off-line and I'll look at the raw data I collected before it shipped. /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Fwd: UTC Receiver Timeout
No one knows what UTC Receiver Timeout means? I Googled for it but only got one hit, which was a passing reference on this list. Joe Gray KA5ZEC -- Forwarded message -- From: Joseph Gray jg...@zianet.com Date: Wed, Oct 7, 2009 at 8:24 PM Subject: UTC Receiver Timeout To: Discussion of precise time and frequency measurement time-nuts@febo.com While sitting at the computer, I just heard the laptop attached to the Z3801A ding at me. Going to look, I see that GPSCon Pro shows a UTC Receiver Timeout. I also had this happen twice on 2 Oct. On that day, after the second timeout, I saw the Z3801A go into holdover for a few minutes. Right now, after the current timeout message, I see the Z3801A is tracking six satellites and not tracking one. Is this an indication that the Oncore or something else is failing? Joe Gray KA5ZEC ___ 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] Tbolt instability
John I have had my TAPR Tbolt for a couple of months now so my sample size of one and experience is rather limited. I have found MANY reasons why my unit did and still does sometimes behave like yours. Sorry for the long answer to your long post, But There is NO single one item that magically fixes everything. In no special order of importance or max effect, I have listed many of the items below that needed to be addressed in order to make mine the best that it could be. Any and all of these items have caused me similar problems as you described, and they may need more than one line to fully explain. Most if not all of these issues have been discussed in detail on the Nuts site before as will as others that I've missed or that have not yet applied to me. Bottom line is that the Tbold is a good little unit for the money and it can be made into a great unit with some TLC. 1) Be sure it has the high resolution Temp sensor, If not CHANGE it. This is a must so that it does not sometimes think it just had a 1 deg temp step. 2) Do not let the case temp change FAST, isolate it from the environment. 3) Keep the case temp from changing at all, I use a small light bulb in a box connected to a modified fish temp controller. 4) Make sure to have a good antenna and it is in a good OUTSIDE location with a good view. 5) make sure the survey location is correct 6) Don't let weak Sat signals jump in and out of range, (I change the default elevation and the sat level) 7) NOT let the unit go into hold over. I've seen that half the time the first holdover will pick a poor starting Dac value. 7b) which is not too bad, BUT when the unit returns from Holdover, it is going to have a giant phase jump. 8) Do not put any pressure on the case top or bottom, put some rubber feet under it in the 4 corners. 9) Do not let it Tilt, move or vibrate it. (I put mine on its zero G axes) 10) Make sure the +12 volt PS does not change voltage or have ANY noise on it. 11) If you want to remove the line freq noise from the output, use a low noise PS on the +12 volts, /or add a lot of cap. 12) Make sure the Dac gain is correct, mine is 3.4, not the 5Hz/ volt default 13) The default TC is way too slow, I've found 500 sec with a damping of 1.5 NOW works good for me. Without the TLC modes, It is safest to leave it at its default of 100 sec and 1.2. 14) Let it run in a long time before judging. It. needs 1 month. The first two weeks, mine was terrible for use as a high precision Nuts quality type reference. 14a) Mine has been going constantly for 2 months, and getting better all the time, but still some times has a little weird behavior, That causes the phase to vary by 20 ns over a few hours, but mostly it now stays within 5 to 10 ns 15) The Number one tool to make sure it is working and to see what it is doing, USE Lady Heater plots (not its ADEV) to verify all is working and to make adjustments. In defense of the Tbolt, It's only real problem is we're asking it to do an order of magnitude better performance than it was ever designed for, Or than is really necessary. Given some TLC, The fact it can even do the unreasonable demands expected by 'nuts' says a lot for it. ws -Original Message- From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of John Green Subject: [time-nuts] Tbolt instability Tbolts seem to have a very good reputation for accuracy and stability. Most comments I have seen compare them favorably to the HP/Symmetricom Z3801. Mine may be OK in the very long term but doesn't look too good in the short term. snip ___ 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] Tbolt instability
WarrenS wrote: 8) Do not put any pressure on the case top or bottom, put some rubber feet under it in the 4 corners. What do you mean by pressure ? Can you explain the pressure issue ? 9) Do not let it Tilt, move or vibrate it. (I put mine on its zero G axes) Which axis is that and how did you determine it ? 12) Make sure the Dac gain is correct, mine is 3.4, not the 5Hz/ volt default How did you determine this value ? 13) The default TC is way too slow, I've found 500 sec with a damping of 1.5 NOW works good for me. Without the TLC modes, It is safest to leave it at its default of 100 sec and 1.2. Ditto on this one as well. Thanks, BillWB6BNQ ___ 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] Tbolt instability
Mark Sims wrote: A lot depends upon the temperature sensor in the Tbolt. ? ?Dallas Semi changed the guts of the sensor ship in such a way that the Tbolt can only get 1 degree resolution out of it. ? Later production Tbolts all have that sensor. ?Does your Tbolt show a mostly flat line temp curve with coarse, ?step-like transitions or one that tracks the temperature rather finely? ? When you hit the thing with the hot air, ?what did the temperature plot do? Also, ?the temperature sensor would do no good inside the OCXO (there is already one in there). ?The Tbolt temperature sensor is used to compensate the unit for temperature effects on the unit as a complete system. ? It is also used for environmental alarms, etc. Mark, Mine is an older unit. I believe it has the better sensor. It seems to read out temperature to maybe .001 degree. When Lady Heather changed the temp scale to 10 mDeg/div, I still saw lots of fine steps. The hot air blast raised the temp 11 degrees C per Lady Heather. I have it in a corrugated box to insulate it somewhat. I was still seeing large temperature excursions with the A/C cycling. I diverted the vent over my work bench and that helped. I finally got LH to report 5E-13 at tau = 10,000. It is definitely temperature that is causing the phase shifts. I needed a reference for a 900 MHz ham repeater I am building and had been having trouble finding anything that wouldn't need frequent adjustment. The Tbolt is the perfect solution to that need,. It should never need attention. ___ 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] Tbolt instability
13) The default TC is way too slow, I've found 500 sec with a damping of 1.5 NOW works good for me. Without the TLC modes, It is safest to leave it at its default of 100 sec and 1.2. Here is a plot showing switching from a TC=100 to TC=400 Notice that the jumps in frequency which are more noticeable at TC=400, are probably caused by the 1 degree sensor in this tbolt. http://www.k5cm.com/z3801%20vs%20various.htm I will put up a plot showing the Tblot in hold over a little later. The short term in hold over looks better, but as you mention there is sometimes a large jump in frequency when it goes into hold over. Regards, Connie K5CM ___ 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] Tbolt instability
Bill - Original Message - From: WB6BNQ WarrenS wrote: 8) Do not put any pressure on the case top or bottom, put some rubber feet under it in the 4 corners. What do you mean by pressure ? Can you explain the pressure issue ? If you squeeze the case or set something on top if it on set it so that it applies some pressure to it's bottom cover all can have small effects on its Freq, much the same as tilting it. 9) Do not let it Tilt, move or vibrate it. (I put mine on its zero G axes) Which axis is that and how did you determine it ? This is an overkill unless you are moving the unit around some and can not be sure it is placed back at the exact same level position. The Null may be any axis and it will very unlikely be on a flat axes. Just tilt it around and see there the freq change effect nulls and reverses its direction. FINE check it by tilting it in any angle and the first 10 deg or so should do nothing and then all tilt directions will cause the same freq anount and direction of change. Using Lady Heather 12) Make sure the Dac gain is correct, mine is -3.4, not the 5Hz/ volt default How did you determine this value ? One way is with an external counter and the unit in disable mode. You can output various small value changes to the Dac and measure their effect on the freq. Using Lady Heather? Or it may take 'trimble monitor' for that because LH may have a S/W bug that effects the Dac out command? The three things Dac Gain effects is the accuracy of the Damping, TC and the accuracy of the OSC Freq plot. If you do not care about them, then not a big lost to leave it uncalibrated. Watch the sign, It's neg! 13) The default TC is way too slow, I've found 500 sec with a damping of 1.5 NOW works good for me. Without the TLC modes, It is safest to leave it at its default of 100 sec and 1.2. Ditto on this one as well. If you mean how or why, 'Tom Van Baak's leapsecond.com is the place search for more info. He is the expert on how to do that using ADEV data. BUT, Simplest is set TC to 330 sec and leave everthing else alone. Assuming you like to tinker, and that you have already taken reasonable steps so the unit does not see large or fast temp changes or any other movement changes, One way is: Start at 500 seconds and 1.5 Damping and if the phase error stays within YOUR acceptable limits over time, change the TC to 1000 second. If the phase error goes outside your acceptable limits decrease the TC to 250 second. One of those 3 values of TC should be good enough for just about everyone. And what is the BEST acceptable phase error to use? Around 15- 25 ns peak over a 1/2 day or so is a good place to start. It depends on the changing environment that the units sees. OR Another way to set it a little coser it is to keep making the TC longer say by x1.4 until the Dac voltage plot noise reduces to a min and then a bit more so the Phase error plot starts to increase a little. all Using Lady Heather plots Thank, BillWB6BNQ ___ 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] Time running backwards down under
Actually, the water goes down the plug hole the correct way here in NZ, as do hurricanes rotate and the moon is the right way up. Anyone claiming otherwise must be upside down. :-) Cheers, Steve 2009/10/8 Jim Palfreyman jim77...@gmail.com: Now I have an enourmous respect for Murray - one of the cleverest people I know, but this time he has shot himself in the foot. The water does not go down the plug hole differently - that is an urban legend. Any difference in direction in a household sink has more to do with residual circular motion in the bowl rather than the coriolis effect. Also, we call hurricanes cyclones. They rotate clockwise which is opposite to what North Americans see in their hurricanes. So technically hurricanes don't rotate the other way here - because we don't have them. :-) :-) :-) 2009/10/8 Murray Greenman murray.green...@rakon.com: Think about it... no it doesn't. Just takes a while to get used to the sun being on the wrong side and the moon being upside down (think about that one!). And yes, the water goes down the plug hole the other way, and hurricanes rotate the other way. However, here in New Zealand we are currently 13 hours ahead of UTC, so well ahead of the rest of the world! Murray ___ 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. -- Steve Rooke - ZL3TUV G8KVD A man with one clock knows what time it is; A man with two clocks is never quite sure. ___ 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] Fwd: UTC Receiver Timeout
Hi Joe, I get these time-outs from GPSCon as well. On my display it says [DATE][TIME] UTC Receiver Timeout Or something similar. It is just a time stamp of when GPSCon is trying to talk to the receiver, and not getting a response before GPSCon times-out. Nothing to worry about. bye, Said In a message dated 10/8/2009 15:48:20 Pacific Daylight Time, jg...@zianet.com writes: No one knows what UTC Receiver Timeout means? I Googled for it but only got one hit, which was a passing reference on this list. Joe Gray KA5ZEC ___ 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] Acitve GPS antenna biasing
Hi Bruce, in response to the active antenna biasing discussion we had a couple of days ago: there is a good reference I ran across with inductor part number, schematic, and layout in the uBlox literature (hardware reference manuals) on the uBlox website. They use a single Murata inductor for GPS antenna biasing. bye, Said In a message dated 10/8/2009 18:30:16 Pacific Daylight Time, sar10...@gmail.com writes: Actually, the water goes down the plug hole the correct way here in NZ, as do hurricanes rotate and the moon is the right way up. Anyone claiming otherwise must be upside down. :-) Cheers, Steve 2009/10/8 Jim Palfreyman jim77...@gmail.com: Now I have an enourmous respect for Murray - one of the cleverest people I know, but this time he has shot himself in the foot. The water does not go down the plug hole differently - that is an urban legend. Any difference in direction in a household sink has more to do with residual circular motion in the bowl rather than the coriolis effect. Also, we call hurricanes cyclones. They rotate clockwise which is opposite to what North Americans see in their hurricanes. So technically hurricanes don't rotate the other way here - because we don't have them. :-) :-) :-) 2009/10/8 Murray Greenman murray.green...@rakon.com: Think about it... no it doesn't. Just takes a while to get used to the sun being on the wrong side and the moon being upside down (think about that one!). And yes, the water goes down the plug hole the other way, and hurricanes rotate the other way. However, here in New Zealand we are currently 13 hours ahead of UTC, so well ahead of the rest of the world! Murray ___ 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. -- Steve Rooke - ZL3TUV G8KVD A man with one clock knows what time it is; A man with two clocks is never quite sure. ___ 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] Tbolt instability
my Tbolts work same of your , you explain very well how your and mine work . i have z3805 rock stable , lpro101 , and Tbolts . i track the signal with my tek 2467b , lpro for trigger , z3805 channel A , tbolts channel B , sweep 500 ps . i read your description , i see on my scope the same . i have also SR620 ( i do not like this counter to much jitter for short time , for long time is good) May be Tbolts OCXO is no good as HP OCXO , may be temperature change in the home , i do not know , but hp 3805 is 10 time better in short time , in long time tbolts is good. But for my personal use i prefer to have short time reference , i no need long time for the moment. Sorry for my bad english but i am italian. regards Alfredo ___ 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] Acitve GPS antenna biasing
Said You mean as in figure 31 on page 40 of http://www.u-blox.com/images/downloads/Product_Docs/LEA-5_NEO-5_TIM-5H_HardwareIntegrationManual(GPS.G5-MS5-09027).pdf http://www.u-blox.com/images/downloads/Product_Docs/LEA-5_NEO-5_TIM-5H_HardwareIntegrationManual%28GPS.G5-MS5-09027%29.pdf The only one for which a nondisclosure agreement isn't required. thats fine for a narrow band solution. If one also wished to receive L2, L5 etc it wont be optimal. Bruce saidj...@aol.com wrote: Hi Bruce, in response to the active antenna biasing discussion we had a couple of days ago: there is a good reference I ran across with inductor part number, schematic, and layout in the uBlox literature (hardware reference manuals) on the uBlox website. They use a single Murata inductor for GPS antenna biasing. bye, Said In a message dated 10/8/2009 18:30:16 Pacific Daylight Time, sar10...@gmail.com writes: Actually, the water goes down the plug hole the correct way here in NZ, as do hurricanes rotate and the moon is the right way up. Anyone claiming otherwise must be upside down. :-) Cheers, Steve 2009/10/8 Jim Palfreyman jim77...@gmail.com: Now I have an enourmous respect for Murray - one of the cleverest people I know, but this time he has shot himself in the foot. The water does not go down the plug hole differently - that is an urban legend. Any difference in direction in a household sink has more to do with residual circular motion in the bowl rather than the coriolis effect. Also, we call hurricanes cyclones. They rotate clockwise which is opposite to what North Americans see in their hurricanes. So technically hurricanes don't rotate the other way here - because we don't have them. :-) :-) :-) 2009/10/8 Murray Greenman murray.green...@rakon.com: Think about it... no it doesn't. Just takes a while to get used to the sun being on the wrong side and the moon being upside down (think about that one!). And yes, the water goes down the plug hole the other way, and hurricanes rotate the other way. However, here in New Zealand we are currently 13 hours ahead of UTC, so well ahead of the rest of the world! Murray ___ 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. http://www.u-blox.com/images/downloads/Product_Docs/LEA-5_NEO-5_TIM-5H_HardwareIntegrationManual(GPS.G5-MS5-09027).pdf ___ 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] Acitve GPS antenna biasing
saidj...@aol.com wrote: Hi Bruce, in response to the active antenna biasing discussion we had a couple of days ago: there is a good reference I ran across with inductor part number, schematic, and layout in the uBlox literature (hardware reference manuals) on the uBlox website. They use a single Murata inductor for GPS antenna biasing. bye, Said For broadband use a powdered iron filled conical choke such as: http://www.piconics.com/BC/bc.pdf May be more useful, provided it is oriented correctly with respect to the microstrip transmission line. Bruce ___ 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] Acitve GPS antenna biasing
Hi Bruce, these are very nice indeed. I used these conical inductors in our 2004 FireFox broad-band synthesizer prototype (working from DC to 1.64GHz), they are quite amazing. But: * you need a microscope and a VERY stable hand to solder them down, and cut-off the unused wire. I damaged quite a few before I figured out how to solder them. And once soldered, they need to be physically protected because they are so extremely fragile * if I remember correctly they won't sell to everyone due to military applications (their main use) * their current handling capacity is limited * And they are very expensive. I ended up designing the FireFox with a series connected bias-t using a 120nH inductor in series to a 150 Ohm power resistor in series to a 2.2uH/270 Ohm resistor combination. That works very well up to over 1.6GHz, and costs pennies compared to $$. bye, Said In a message dated 10/8/2009 19:33:06 Pacific Daylight Time, bruce.griffi...@xtra.co.nz writes: For broadband use a powdered iron filled conical choke such as: http://www.piconics.com/BC/bc.pdf May be more useful, provided it is oriented correctly with respect to the microstrip transmission line. Bruce ___ 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] Any Time nuts in AU?
Or current ones. ;-) 2009/10/8 A.H.Schmidt hor...@iinet.net.au: The rest is at home in the sheds of ex Telstra employees ___ 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] Fwd: UTC Receiver Timeout
Thanks, Said. I was concerned that something was going bad. When I saw the unit go into holdover shortly after the second one, I was really worried. Maybe just a coincidence. Joe Gray KA5ZEC On Thu, Oct 8, 2009 at 7:30 PM, saidj...@aol.com wrote: Hi Joe, I get these time-outs from GPSCon as well. On my display it says [DATE][TIME] UTC Receiver Timeout Or something similar. It is just a time stamp of when GPSCon is trying to talk to the receiver, and not getting a response before GPSCon times-out. Nothing to worry about. bye, Said In a message dated 10/8/2009 15:48:20 Pacific Daylight Time, jg...@zianet.com writes: No one knows what UTC Receiver Timeout means? I Googled for it but only got one hit, which was a passing reference on this list. Joe Gray KA5ZEC ___ 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.
