Re: [time-nuts] 3.0 GHz Channel 3 Installation in Agilent 53132A Counter
Hi Jim Will send direct shortly, if nothing arrives let me know and I'll try again. Regards Nigel GM8PZR In a message dated 19/03/2014 01:13:31 GMT Standard Time, jsrobb...@earthlink.net writes: Thanks everyone for the thoughts. Nigel, I am not seeing the references to pin 9 connected to +12 and 10 to ground on the documentation I have.Perhaps you could send along your component level service manual. Address is jsrobb...@earthlink.net. Many thanks. Jim N1JR ___ 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] 3.0 GHz Channel 3 Installation in Agilent 53132A Counter
Hi Jim The PC containing my archives is busy and I can't pull any files off right now, sorry about that, but I've confirmed that the component level service data I have is the same February 2007 version as can be found here.. http://cp.literature.agilent.com/litweb/pdf/5989-6308EN.pdf Information regarding the pin usage is at the top left of page 20, Main Board schematic page 3 of 4, and the connection data from the expansion PCB is at the bottom right of the Channel 3 schematic on Page 8. That's all I was going on, I haven't checked any further what the effect might be of altering what the motherboard sees from those pins. Regards Nigel GM8PZR In a message dated 19/03/2014 01:13:31 GMT Standard Time, jsrobb...@earthlink.net writes: Thanks everyone for the thoughts. Nigel, I am not seeing the references to pin 9 connected to +12 and 10 to ground on the documentation I have.Perhaps you could send along your component level service manual. Address is jsrobb...@earthlink.net. Many thanks. Jim N1JR ___ 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] NIST time services
I would, but I don't have the time at the moment :) Didier KO4BB On March 19, 2014 12:18:23 AM CDT, Tom Van Baak t...@leapsecond.com wrote: If you can design a system that can handle 6.5 billion requests per day, this opportunity is for you... https://www.fbo.gov/spg/DOC/NIST/AcAsD/RFI_InternetTimeServiceComments/listing.html Solicitation Number: RFI_InternetTimeServiceComments Synopsis: Added: Mar 18, 2014 9:46 am SUMMARY: National Institute of Standards and Technology (NIST), Department of Commerce, seeks information from the public on NIST's potential transition of time services from a NIST-only service to private sector operation of an ensemble of time servers that will provide NIST-traceable time information in a number of different formats over the public Internet. ___ 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. -- Sent from my Motorola Droid Razr 4G LTE wireless tracker while I do other things. ___ 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] 3.0GHz Channel 3 installation in Agilent 53132A counter
Many thanks for all the replies. Nigel, thank you for the link. I did have this pdf, but was not reading it correctly. It has been suggested that perhaps the counter main board was set up (modified) for a 12GHz channel 3. That would have required some mods to the actual main board, but I am not sure what they would be to check them out. The FW is 3703, so the counter is pretty current. I have a second 53132A with a 3.0GHz channel 3 installed which works properly. I will try some swapping of boards to see if the issue is with the new channel 3 board or with the new counter's main board. Jim Robbins N1JR ___ 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] NIST time services
On 3/18/14 10:18 PM, Tom Van Baak wrote: If you can design a system that can handle 6.5 billion requests per day, this opportunity is for you... https://www.fbo.gov/spg/DOC/NIST/AcAsD/RFI_InternetTimeServiceComments/listing.html Solicitation Number: RFI_InternetTimeServiceComments For those that are unfamiliar with the ways of US Government contracting, this is NOT a request for proposals to provide the service. It's more of a preliminary step to identify potential bidders, gather background information, shake the trees to find out who the potential players are, as well as help make a decision on whether it's even a good idea. (e.g. it might feature into a make vs buy report) We do this at NASA when we want to make sure we haven't missed something in the marketplace. These days, Government folks don't go to as many conferences and almost no trade shows. So you find out what's available by exercising google or bing, which is not such a great way to find niche products and services. Someone who's got a great way to do reliable, accurate time distribution over the internet might not have a big web presence, or might be overshadowed by something similar that has been heavily Search Engine Optimized. This is also a way for people who aren't necessarily interested in providing the service to give comments to NIST about potential issues that may be of concern. Those kinds of comments might wind up changing the eventual procurement, or might even result in a report that says nope, not worth privatizing this, because of reasons A, B, and C. that's the crux of question 7 at the end What are advantages and disadvantages of NIST's potential transition of time services from a NIST-only service to private sector operation... A lot of the questions at the end of the RFI are things that get discussed on time-nuts from time to time. ___ 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] 3.0GHz Channel 3 installation in Agilent 53132A counter
Thanks for everyone's help here. I have done some further sleuthing. I have a second 53132A which has a 3.0GHz Channel 3. So, I switched the new channel 3 board into the old 53132A and it reads properly. Then, I switched the old 3.0GHz Channel 3 board into the new 53132A and it also read four times (4x) the input frequency. From this I conclude that the issue is with the new 53132A counter box and not the channel 3 board. Then I powered up each counter and measured at the pins on the ribbon cable connector at the Channel 3 board to the main board on both the new and old counters (channel 3 boards plugged in and powered). They each read the same voltages and/or grounds (pin1 = 2v; 2,5,7,9,10 = ground; 3,8 = +12v; 4 = -12v with numbering based on 1 shown on channel board). Someone suggested that maybe the new main board had been set up for the 12.5 or 6GHz channel 3 but was sold without that channel. The idea was that such a main board would cause a 4x reading. To my mind this is opposite to what I would think in that the division ratio for 12.5 or 6GHz would be higher than the ratio for the 3.0GHz board and would result in a fraction of the frequency rather than 4x frequency. Of course, it could be a FW mod (rather than a HW mod) which has been applied also. Any other thoughts are much appreciated. 73, Jim Robbins N1JR ___ 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] NIST time services
So they want to in-invent NTP? I think NTP already services way more than 6.5 billion per day. The problem with NTP is while it is nearly optimal and provides the best time accuracy for a given hardware/network setup it is not technically traceable even if the time really is from NIST indirectly. I think you could fix this traceability problem with some rules about how to write the configuration files, no new software. For example NTP already handles cryptographic authentication. Make the use of this monitory so that then you know you are talking to a NIST referenced server. On Tue, Mar 18, 2014 at 10:18 PM, Tom Van Baak t...@leapsecond.com wrote: If you can design a system that can handle 6.5 billion requests per day, this opportunity is for you... https://www.fbo.gov/spg/DOC/NIST/AcAsD/RFI_InternetTimeServiceComments/listing.html Solicitation Number: RFI_InternetTimeServiceComments Synopsis: Added: Mar 18, 2014 9:46 am SUMMARY: National Institute of Standards and Technology (NIST), Department of Commerce, seeks information from the public on NIST's potential transition of time services from a NIST-only service to private sector operation of an ensemble of time servers that will provide NIST-traceable time information in a number of different formats over the public Internet. ___ 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. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 3.0GHz Channel 3 installation in Agilent 53132A counter
On 3/19/2014 8:26 AM, James Robbins wrote: Thanks for everyone's help here. I have done some further sleuthing. I have a second 53132A which has a 3.0GHz Channel 3. So, I switched the new channel 3 board into the old 53132A and it reads properly. Then, I switched the old 3.0GHz Channel 3 board into the new 53132A and it also read four times (4x) the input frequency. From this I conclude that the issue is with the new 53132A counter box and not the channel 3 board. Then I powered up each counter and measured at the pins on the ribbon cable connector at the Channel 3 board to the main board on both the new and old counters (channel 3 boards plugged in and powered). They each read the same voltages and/or grounds (pin1 = 2v; 2,5,7,9,10 = ground; 3,8 = +12v; 4 = -12v with numbering based on 1 shown on channel board). Someone suggested that maybe the new main board had been set up for the 12.5 or 6GHz channel 3 but was sold without that channel. The idea was that such a main board would cause a 4x reading. To my mind this is opposite to what I would think in that the division ratio for 12.5 or 6GHz would be higher than the ratio for the 3.0GHz board and would result in a fraction of the frequency rather than 4x frequency. Of course, it could be a FW mod (rather than a HW mod) which has been applied also. Any other thoughts are much appreciated. 73, Jim Robbins N1JR ___ 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. Jim, I think the problem is with the Ch3 board as the issue migrates to the other counter with the board. Also the know good board works properly with the first counter that has issues with that board. I don't think that it would be a firmware issue as the board from the working counter works properly in the other counter with the non-working board. Hope this helps Randy, KI6WAS ___ 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] 3.0GHz Channel 3 installation in Agilent 53132A counter
No, the suggestion makes perfect sense. A 12 GHz input board likely has an internal prescaler with a division ratio that is 4 times that of a 3 GHz input board, in order to have the main counter running at the same internal frequency. For example, a 3 GHz input might divide by 32 while a 12 GHz input might divide by 128, so that both feed a signal in the 0 to 100 MHz range to the main counter circuits. (And the 5 GHz input might divide by 64...) When the firmware goes to display what the main counter measured, it has to multiply by the prescaler ratio to obtain the original input frequency. If this multiply happens on the main board (e.g. in a FPGA or CPU), it needs to be told which prescaler division ratio was used. If the firmware thinks the 12 GHz input is installed instead of the 3 GHz input, it will multiply by 128 instead of 32, and the displayed frequency will be 4 times the actual frequency (since the prescaler actually divided by 32). (The prescaler division ratios may not be 32 and 128; the actual values don't matter. As long as the 12 GHz option uses 4 times the prescaler divisor of the 3 GHz option, the display error will be a factor of 4). - Dave On Wed, Mar 19, 2014 at 11:26 AM, James Robbins jsrobb...@earthlink.net wrote: Someone suggested that maybe the new main board had been set up for the 12.5 or 6GHz channel 3 but was sold without that channel. The idea was that such a main board would cause a 4x reading. To my mind this is opposite to what I would think in that the division ratio for 12.5 or 6GHz would be higher than the ratio for the 3.0GHz board and would result in a fraction of the frequency rather than 4x frequency. 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] Fwd: Re: NIST time services
Original Message Subject: Re: [time-nuts] NIST time services Date: Wed, 19 Mar 2014 10:21:17 -0700 From: Jim Lux jim...@earthlink.net To: time-nuts@febo.com On 3/19/14 9:50 AM, Chris Albertson wrote: So they want to in-invent NTP? I think NTP already services way more than 6.5 billion per day. The problem with NTP is while it is nearly optimal and provides the best time accuracy for a given hardware/network setup it is not technically traceable even if the time really is from NIST indirectly. They are well aware of NTP.. they serve 6.5 billion a day *from NIST* and that's what they are looking at potentially outsourcing or changing. And, of course, there's the legally traceable aspect. I think you could fix this traceability problem with some rules about how to write the configuration files, no new software. For example NTP already handles cryptographic authentication. Make the use of this monitory so that then you know you are talking to a NIST referenced server. That's very possible, and you could respond to the RFI and tell them so. Could you set up a legally traceable set of multiple tiers? What would the mechanics of this be? That's really what the RFI is all about.. tell us what you think we need to know.. They'll get responses that are overlapping existing knowledge, for sure. And nobody is going to respond with something that is confidential or proprietary or telegraphs a future product line, because all the RFI responses are essentially public 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.
[time-nuts] 3.0GHz Channel 3 installation in Agilent 53132A Counter
I think I may need to clarify my prior posting. Both old and new Channel 3 boards work fine (and read correctly) in my older 53132A counter. Both old and new Channel 3 boards fail to work properly in (and read 4x actual) the newer 53132A counter. So I think the problem is in the newer main 53132A box. As far as my understanding of the division ratios, I understand my error now. Thank you Dave (and some others). I have done some further testing and discovered one of HP/Agilent's little tricks. The main counter board channel 3 ribbon cable socket pin numbering does not conform to the channel 3 board ribbon cable socket numbering (they are crisscrossed). (I can supply the shifted numbers if anyone is interested.) However, my search for suspected unwanted zero ohm resistors left in the new box (to set the counter up for a 5 or 12.5GHz channel 3) has resulted in no joy and only a large headache and sore eyes:( Thanks everyone for trying to help here. It was supposed to be a plug and play addition to my counter. So much for the plan. Jim Robbins N1JR ___ 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] 3.0GHz Channel 3 installation in Agilent 53132A Counter
On 2014-03-19 16:00, James Robbins wrote: I think I may need to clarify my prior posting. Both old and new Channel 3 boards work fine (and read correctly) in my older 53132A counter. Both old and new Channel 3 boards fail to work properly in (and read 4x actual) the newer 53132A counter. So I think the problem is in the newer main 53132A box. As far as my understanding of the division ratios, I understand my error now. Thank you Dave (and some others). I have done some further testing and discovered one of HP/Agilent's little tricks. The main counter board channel 3 ribbon cable socket pin numbering does not conform to the channel 3 board ribbon cable socket numbering (they are crisscrossed). (I can supply the shifted numbers if anyone is interested.) However, my search for suspected unwanted zero ohm resistors left in the new box (to set the counter up for a 5 or 12.5GHz channel 3) has resulted in no joy and only a large headache and sore eyes:( Thanks everyone for trying to help here. It was supposed to be a plug and play addition to my counter. So much for the plan. Presumably you looked for obvious changes between the main boards? Have you checked the FW ROM markings or could you dump and compare the ROM contents? Thought of trying a straight (uncrossed) ribbon cable between the channel 3 board and the newer counter? That's the kind of change that might be done to reduce costs on newer model upgrades requiring a factory mod. -- Take care. Thanks, Brian Inglis ___ 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] 3.0GHz Channel 3 installation in Agilent 53132A Counter
Hi Jim: I've seen a similar problem when one end of a ribbon cable connector is soldered to the wrong side of a PCB. Maybe you can unsolder a connector and install it on the other side? Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html James Robbins wrote: I think I may need to clarify my prior posting. Both old and new Channel 3 boards work fine (and read correctly) in my older 53132A counter. Both old and new Channel 3 boards fail to work properly in (and read 4x actual) the newer 53132A counter. So I think the problem is in the newer main 53132A box. As far as my understanding of the division ratios, I understand my error now. Thank you Dave (and some others). I have done some further testing and discovered one of HP/Agilent's little tricks. The main counter board channel 3 ribbon cable socket pin numbering does not conform to the channel 3 board ribbon cable socket numbering (they are crisscrossed). (I can supply the shifted numbers if anyone is interested.) However, my search for suspected unwanted zero ohm resistors left in the new box (to set the counter up for a 5 or 12.5GHz channel 3) has resulted in no joy and only a large headache and sore eyes:( Thanks everyone for trying to help here. It was supposed to be a plug and play addition to my counter. So much for the plan. Jim Robbins N1JR ___ 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] 3.0GHz Channel 3 installation in Agilent 53132A Counter
Jim the 5 and 12.8GHz modules are the same part and the software/firmware set the upper freq limit. I assume at least the 12.8 GHz option must be unlocked/accessed most likely through the key pad. The 5GHz may be plug and play. Thomas Knox From: jsrobb...@earthlink.net Date: Wed, 19 Mar 2014 18:00:09 -0400 To: time-nuts@febo.com Subject: [time-nuts] 3.0GHz Channel 3 installation in Agilent 53132A Counter I think I may need to clarify my prior posting. Both old and new Channel 3 boards work fine (and read correctly) in my older 53132A counter. Both old and new Channel 3 boards fail to work properly in (and read 4x actual) the newer 53132A counter. So I think the problem is in the newer main 53132A box. As far as my understanding of the division ratios, I understand my error now. Thank you Dave (and some others). I have done some further testing and discovered one of HP/Agilent's little tricks. The main counter board channel 3 ribbon cable socket pin numbering does not conform to the channel 3 board ribbon cable socket numbering (they are crisscrossed). (I can supply the shifted numbers if anyone is interested.) However, my search for suspected unwanted zero ohm resistors left in the new box (to set the counter up for a 5 or 12.5GHz channel 3) has resulted in no joy and only a large headache and sore eyes:( Thanks everyone for trying to help here. It was supposed to be a plug and play addition to my counter. So much for the plan. Jim Robbins N1JR ___ 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] Aircraft ping timing
Those who say the missing aircraft should be searched along the two corridors, what measurement are they relying on? I think it is a one-way measurement of time-stamped pings, which implies good synchronization of clocks between a geosynchronous satellite and a moving aircraft. Antonio I8IOV ___ 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] Aircraft ping timing
They only got one ping from INMARSAT at 64E above the Indian Ocean. There was no other ping to triangulate the position. One ping projects a circle on the Earth. The maximum flying range of the plane determined the ends of the NE and SE arcs of that circle. The news only gets stranger as time goes on. Bill Hawkins -Original Message- From: iov...@inwind.it Sent: Wednesday, March 19, 2014 6:46 PM Those who say the missing aircraft should be searched along the two corridors, what measurement are they relying on? I think it is a one-way measurement of time-stamped pings, which implies good synchronization of clocks between a geosynchronous satellite and a moving aircraft. Antonio I8IOV ___ 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] Aircraft ping timing
My question was on what would be the expected accuracy of the circle's radius. Antonio I8IOV Messaggio originale Da: b...@iaxs.net Data: 20/03/2014 1.21 They only got one ping from INMARSAT at 64E above the Indian Ocean. There was no other ping to triangulate the position. One ping projects a circle on the Earth. The maximum flying range of the plane determined the ends of the NE and SE arcs of that circle. The news only gets stranger as time goes on. Bill Hawkins -Original Message- From: iov...@inwind.it Sent: Wednesday, March 19, 2014 6:46 PM Those who say the missing aircraft should be searched along the two corridors, what measurement are they relying on? I think it is a one-way measurement of time-stamped pings, which implies good synchronization of clocks between a geosynchronous satellite and a moving aircraft. Antonio I8IOV ___ 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] Aircraft ping timing
It depends on how accurately the bird can measure the round-trip time: 1 us = ca 500' 10 us = ca 1 mile 100us = ca 10 miles 1 ms = ca 100 miles The arcs are loci of constant round trip time, projected on the globe. -John === My question was on what would be the expected accuracy of the circle's radius. Antonio I8IOV Messaggio originale Da: b...@iaxs.net Data: 20/03/2014 1.21 They only got one ping from INMARSAT at 64E above the Indian Ocean. There was no other ping to triangulate the position. One ping projects a circle on the Earth. The maximum flying range of the plane determined the ends of the NE and SE arcs of that circle. The news only gets stranger as time goes on. Bill Hawkins -Original Message- From: iov...@inwind.it Sent: Wednesday, March 19, 2014 6:46 PM Those who say the missing aircraft should be searched along the two corridors, what measurement are they relying on? I think it is a one-way measurement of time-stamped pings, which implies good synchronization of clocks between a geosynchronous satellite and a moving aircraft. Antonio I8IOV ___ 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] 3.0GHz Channel 3 installation in Agilent 53132A Counter
FYI: Here is the link to the 53132 CLIP. http://www.home.agilent.com/agilent/redirector.jspx?action=refcname=AGILENT _EDITORIALckey=1119025lc=engcc=USnfr=-33788.536880944.00 It wasn't there last I checked. John K1AE ___ 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] Aircraft ping timing
Messaggio originale Da: j...@quikus.com Data: 20/03/2014 1.47 It depends on how accurately the bird can measure the round-trip time: 1 us = ca 500' 10 us = ca 1 mile 100us = ca 10 miles 1 ms = ca 100 miles The arcs are loci of constant round trip time, projected on the globe. This is valid for round trip and for the signal path which in this case is the line generating the cone having the bird at its apex. The radius of the circle at earth is another thing, and the error should be multiplied by some factor which depends on the angle at the apex, being the earth's surface curve. Hence I tought that the timing is crucial. Add to this that I understood it was not a ping as we usually mean, but a one way signal (aircraft to satellite). Hence my question. Antonio I8IOV -John === My question was on what would be the expected accuracy of the circle's radius. Antonio I8IOV Messaggio originale Da: b...@iaxs.net Data: 20/03/2014 1.21 They only got one ping from INMARSAT at 64E above the Indian Ocean. There was no other ping to triangulate the position. One ping projects a circle on the Earth. The maximum flying range of the plane determined the ends of the NE and SE arcs of that circle. The news only gets stranger as time goes on. Bill Hawkins -Original Message- From: iov...@inwind.it Sent: Wednesday, March 19, 2014 6:46 PM Those who say the missing aircraft should be searched along the two corridors, what measurement are they relying on? I think it is a one-way measurement of time-stamped pings, which implies good synchronization of clocks between a geosynchronous satellite and a moving aircraft. Antonio I8IOV ___ 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] Aircraft ping timing
Hi Antonio: It's my understanding that the satellite sends a ping to each aircraft in it's low gain antenna pattern once every hour by aircraft ID number. The aircraft replies with a very short data packet that's time stamped (but without any location or other info other than the ID). The difference between the time stamp on the ping and the received message is the ping time. The idea is to have some idea which of the spot beams to use if someone on the plane wanted to make a phone call. As it happens MH370 does not have first class or sat phones, but this is the default system for everyone. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html iov...@inwind.it wrote: Messaggio originale Da: j...@quikus.com Data: 20/03/2014 1.47 It depends on how accurately the bird can measure the round-trip time: 1 us = ca 500' 10 us = ca 1 mile 100us = ca 10 miles 1 ms = ca 100 miles The arcs are loci of constant round trip time, projected on the globe. This is valid for round trip and for the signal path which in this case is the line generating the cone having the bird at its apex. The radius of the circle at earth is another thing, and the error should be multiplied by some factor which depends on the angle at the apex, being the earth's surface curve. Hence I tought that the timing is crucial. Add to this that I understood it was not a ping as we usually mean, but a one way signal (aircraft to satellite). Hence my question. Antonio I8IOV -John === My question was on what would be the expected accuracy of the circle's radius. Antonio I8IOV Messaggio originale Da: b...@iaxs.net Data: 20/03/2014 1.21 They only got one ping from INMARSAT at 64E above the Indian Ocean. There was no other ping to triangulate the position. One ping projects a circle on the Earth. The maximum flying range of the plane determined the ends of the NE and SE arcs of that circle. The news only gets stranger as time goes on. Bill Hawkins -Original Message- From: iov...@inwind.it Sent: Wednesday, March 19, 2014 6:46 PM Those who say the missing aircraft should be searched along the two corridors, what measurement are they relying on? I think it is a one-way measurement of time-stamped pings, which implies good synchronization of clocks between a geosynchronous satellite and a moving aircraft. Antonio I8IOV ___ 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] 3.0GHz Channel 3 installation in Agilent 53132ACounter
http://cp.literature.agilent.com/litweb/pdf/5989-6308EN.pdf See also: http://www.febo.com/pipermail/time-nuts/2009-February/036507.html http://www.febo.com/pipermail/time-nuts/2014-February/082545.html FYI: Here is the link to the 53132 CLIP. http://www.home.agilent.com/agilent/redirector.jspx?action=refcname=AGILENT_EDITORIALckey=1119025lc=engcc=USnfr=-33788.536880944.00 ___ 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] Aircraft ping timing
On 3/19/14 5:21 PM, Bill Hawkins wrote: They only got one ping from INMARSAT at 64E above the Indian Ocean. There was no other ping to triangulate the position. One ping projects a circle on the Earth. The maximum flying range of the plane determined the ends of the NE and SE arcs of that circle. The news only gets stranger as time goes on. not time based...from what I understand it's based on a received power estimate, matched against antenna patterns. Not particularly accurate. The power measurement is probably good to 0.2 dB (at best). If the transmit antenna's attitude isn't in the nominal straight and level (e.g. plane is banking, or parked on ground, perhaps with a tarp placed by a overweight gentleman holding a white furry cat on his lab?) I did some back of the envelopes and there's a good many 100s of km uncertainty in range. ___ 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] Aircraft ping timing
A lot of these satellites have footprints for each antenna. I don't know if the footprints are narrow enough to track a plane. ___ 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.
