Re: [time-nuts] HP 58503A service manual with schematics
John, Most time nuts have searched for this particular manual at one stage. I am afraid it is unobtainium. marks -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of gianni Sent: Thursday, 29 May 2014 7:09 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] HP 58503A service manual with schematics hi John I am new in the list but not in the art here a lot of manuals http://exodus.poly.edu/~kurt/manuals/manuals/HP%20Agilent/ Gianni In 28 maggio 2014, starb...@uplink.net scritto: Hello to the time experts, I own a nice HP-58503A and I would be happy to find a pdf version of the complete service manual for it. Is somebody in the position to help me or to give me a hint where I could find it? Thank you very much, regards, John ___ 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] New NIST Time Code to Boost Reception for Radio-Controlled Clocks
Good morning to the group I do have the extendwave chip sheets. But they are 668K generally in size so can not send through Time-nuts. I have sent them to Scott already. Regards Paul WB8TSL On Sat, May 31, 2014 at 11:34 PM, Alexander Pummer alex...@ieee.org wrote: here is a description how a receiver works for a time signal with very similar modulation http://caxapa.ru/thumbs/417284/Engeler_DCF77.pdf 73 KJ6UHN On 5/31/2014 2:23 PM, paul swed wrote: I had reached out several times to the new wwvb chip maker for this timecode. And though first run chips were available they are not to us unless we want 1000 of them. Also pricing is unclear. That said yes the intent is to receive time. The new chip doesn't easily allow a way to d-psk the signal. Though it can be helpful. Regards Paul WB8TSL On Sat, May 31, 2014 at 4:31 PM, Brooke Clarke bro...@pacific.net wrote: Hi: What are the left two digits telling us? http://www.nist.gov/pml/div688/wwvb-030513.cfm I've emailed John Lowe James Burrus the above question and for more information about the different transmission modes as well as more information about the hardware shown on the above web page. -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html ___ 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.
Re: [time-nuts] Beginner question - unexpected possible jitter in 1 PPS output of Motorola ONCORE UT+ module
Thank you, Tom - I appreciate the advice. I am using a 74HC390 in the (divide-by-20, square wave output) divider chain, and sure enough, after looking more closely at the data sheet, it clocks on the FALLING edge (I thought otherwise - wrong)! I will stick an inverter in the path and that will probably fix it. Will update again once that's taken care of. Dave Check rising/falling edge times, check trigger levels, check signal levels and load. Are you DC or AC coupled. How about power supply noise and grounding? Which edge are you actually triggering on? Is there crosstalk with the Tx line. It is extremely unlikely that there's a problem with the UT+ itself -- this series of Motorola Oncore GPS boards has served the time frequency community for two decades with no problems, or jitter, or off-by-100us errors. It will be fun to meticulously track down the bug; don't just make it go away and move on. We will all learn from this interesting problem. I'll trade you a perfect UT+ if you give up. At some point we time nuts stop getting excited about what works and delight in what doesn't, and why. ___ 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] Beginner question - unexpected possible jitter in 1 PPS output of Motorola ONCORE UT+ module
Thanks to Tom, Jean-Louis and Chris for all of the helpful advice. Problem is now fixed. First problem was obvious - the 74HC390 I use as a divider clocks on negative-going transition. Added inverter, and the problem appeared to still be present (!) Next problem was not so obvious - my very cheap benchtop chinese frequency counter (a Zhaoxin HC-2700L, bought on ebay, and retrofitted with a divided-by-two Pletronics 26 MHz VCOCXO as timebase, which were for sale cheaply on ebay a few years ago) turns out to have a bug/defect in the totalizer mode; when count transitions from 99 999 999 to 00 000 000, the counter ignores its input for a few milliseconds while it processes something, so my original plan to count for 10 seconds (expecting to see 30 000 000, which is 130 million with the hundred-million digit wrapped off) didn't pan out. Small change to the counter circuit and I now count a series of 1-second intervals, each of 13 MHz reference oscillator in the counter. I adjusted the counter's timebase VCOCXO bias input so that counting for seven 1-second intervals shows 91 000 000 (13 000 000 * 7). There seems to be a +/- 1 count uncertainty, likely due to absence of synchronization between the counter's timebase and the 1 PPS signal, but this accomplishes what I set out to do, which was a cheap-and-dirty (but certainly not quick!) calibration of the counter's timebase. Thanks for everyone's advice and support! Dave To: jl.on...@free.fr, Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Beginner question - unexpected possible jitter in 1 PPS output of Motorola ONCORE UT+ module Message-ID: CABbxVHvpyUYZfP7=zztTKRXGr+F=k7DBYCzNLwAG04Tr=3_...@mail.gmail.com Content-Type: text/plain; charset=UTF-8 I posted here some days ago an admission that I did exactly this by accident once. It is a very hard problem to debug because everything works just fine, except for the very high jitter. So I go looking for noise and what not.The problem was a wrong number of inverters. On Sat, May 31, 2014 at 7:58 PM, Jean-Louis Oneto jl.on...@free.fr wrote: . So if your divider is clocked on the falling edge of the 1PPS, you can expect a 1 ms jitter... -- 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.
