Re: [time-nuts] Time Nut Pickens at the MIT Flea ?
I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ 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] 10 MHz output level from DATUM 9390...
Burt - On the scope I see 950mv RMS with 50 ohm termination, 1.5V RMS with 1M. This is on a 9390-6000 OCXO with the default timing output configuration, 10MHz on J7. Hope this helps. Paul - K9MR On Dec 15, 2012, at 4:21 PM, Burt I. Weiner wrote: Gang, Does anyone have a DATUM 9390 series GPS receiver that can tell me what the (50 Ohm) terminated output level of the 10 MHz spigot is. One of mine started spurring and the other one is clean, but seems way to high in output level. Thanks, Burt, K6OQK Burt I. Weiner Associates Broadcast Technical Services Glendale, California U.S.A. b...@att.net www.biwa.cc K6OQK ___ 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] FE-5682A coming, any info?
The -48V RTN should be the 'positive' side and the POWER -48V should be the 'negative' side. On normal installations the -48V is a black wire, the -48V return is a red wire. It's like having a 'positive ground'. (I've used, manufactured, sold, and installed 48V Telco gear.) On most Telco gear both are isolated from earth ground - but you should check. A current limited supply would be nice for initial startup, but I don't think you'll have any issues. You should in any case, fuse it. Ziggy On 11/21/2012 09:10 AM, Fabio Eboli wrote: Thank you, Peter and Paul. Now I see that the pinout is almost identical to LPRO-101, the only difference are pins 8 and 10 for power supply. That's nice, I like the external C-Field control, and monitor voltage for lamp, they can be useful. I'm not familiar with telco power supplies, I know only that they used 48V with positive to ground. So the supply should be 48V, positive to pin 8 and negative to 10 ? Should I expect the GND to be connected to pin 8? Or it will be floating at middle voltage (hence the 19 to 32V rating), in this case all I need will be a dual 24V psu. Fabio. This message was sent using IMP, the Internet Messaging Program. ___ 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] Datum/Exactime 9390-6000
Just thought I'd give a progress report. I've successfully placed a micro (Arduino) between the GPS and the system board, can spit out the packets in hex, and inject/modify data on the fly. So I can add 1024 to the GPS week and the unit does the date conversion correctly. But it gets more interesting. What I've found is that the GPS module has a nonstandard firmware. It still sends TSIP, but the GPS time packet 0x41 has a different format: Header (0x10) GPS time of week (4 byte single precision float) GPS week number (integer) GPS/UTC offset or leap second count (integer) ??? 4 bytes Trailer (0x10 0x03) For reference, a standard TSIP GPS time packet 0x41 is: Header (0x10) GPS time of week (4 byte single precision float) GPS week number (integer) GPS/UTC offset (4 byte single precision float) Trailer (0x10 0x03) Instead of changing the week number, I can change the offset from 15 to 17 and the unit correctly flips to the next epoch, showing the right day and year. I'm off by 2 seconds then, but it proves that field is used as the leap second count. The next four bytes in question are not just the GPS time shifted. If I can get this decoded, I may be able to use a more modern receiver with better PPS performance. Some snippets of data are below in case it looks familiar to anyone. There's something nagging at me, but it's eluding me for now. If anyone would like to help, I would much appreciate it and we could continue off list. 10 41 45 5B E7 6D 06 9E 00 0F 30 C4 7E 56 10 03 (bytes in red decoded as binary) 10 41 45 5C 38 D9 06 9E 00 0F 30 C4 7D 39 10 03 0011 1100 0100 0111 1101 0011 1001 10 41 45 5C 8C B4 06 9E 00 0F 30 C4 7C 13 10 03 0011 1100 0100 0111 1100 0001 0011 10 41 45 5C EE 04 06 9E 00 0F 30 75 F5 7E 10 03 0011 0111 0101 0101 0111 1110 10 41 45 5D 3E C9 06 9E 00 0F 30 75 F3 49 10 03 0011 0111 0101 0011 0100 1001 10 41 45 5D 91 91 06 9E 00 0F 30 75 F1 06 10 03 0011 0111 0101 0001 0110 10 41 45 5D F2 93 06 9E 00 0F 30 75 EE 5F 10 03 I thought the GPS week increment might show something interesting, but it wasn't really: 10 41 49 13 A7 80 06 9D 00 0F 31 24 FF A0 10 03 10 41 49 13 A7 C4 06 9D 00 0F 31 24 FF D3 10 03 10 41 3F A7 0A 3D 06 9E 00 0F 31 25 00 10 10 10 03 (extra 0x10 is an escaped inline value) 10 41 40 BE 97 8D 06 9E 00 0F 31 25 00 47 10 03 10 41 41 2C 87 2B 06 9E 00 0F 31 25 00 81 10 03 Paul On Jun 12, 2012, at 12:26 PM, Ziggy wrote: The GPS unit is a module, which seems to be a a Trimble SVeeSix-CM3, or variant of some kind. It's marked 26889-81 on a sticker and 25040- -D silk screened on the board. Just as an interesting observation: This GPS module has two MCX connectors, one on the top of the board for the antenna and one on the bottom which mates with the system board. Directly adjacent to this is a 16.368 (or thereabouts) TCXO can. It works with a standard antenna, so it looks like this is setup to work with both downconverting and standard antennas. I had to go to the Internet Archive to find the old Trimble page (http://www.trimble.com/y2kwnro/index2.htm) on Y2k/WNRO status. While this specific module wasn't listed, it didn't look encouraging. I do have a Trimble ACE III receiver which I am going to try using tonight. It is supposed to report the absolute GPS week since 06 January 1980 as an integer value and not truncated to 10 bits. Trimble says: The ACE III GPS module has been designed to handle WNRO, and there are no problems with either dates or first fix after WNRO through the year 2015. Not sure what happens after 2015... Note that due to the 16.368MHz TCXO can being right next to the GPS module, I had to modify the ACE III by changing the connector type to match the existing connector and move it to the other side of the board. I'll report back with the results. Maybe I'll get lucky for once. Paul On 06/12/2012 03:52 AM, Azelio Boriani wrote: Is the GPS unit built-in (TBolt-like) or is it a separate module? Maybe there is a firmware update for the GPS unit itself to fix the rollover problem. On Tue, Jun 12, 2012 at 5:26 AM, Ziggyzig...@pumpkinbrook.com wrote: I've recently acquired one of these, primarily to use as an alternative to (and for comparison with) my Thunderbolt. This was a DC model that was inoperative when I received it and at $225 (price from the OEM) to replace the failed DC-DC converter, I installed an AC supply. So far, so good. The unit powers up, tracks, locks the OCXO and things look generally good. I'm giving it some burn in time before I try to characterize it. However, I have a couple of issues. I did search the archives, and have contacted Symmetricom (who politely told me this unit was obsoleted 2 generations of product ago :) The menus and serial command responses do not match any version of the manual that I can find, although the Datum 9390 manual on Didier's site is pretty close on the commands. Does anyone
Re: [time-nuts] Datum/Exactime 9390-6000
The GPS unit is a module, which seems to be a a Trimble SVeeSix-CM3, or variant of some kind. It's marked 26889-81 on a sticker and 25040- -D silk screened on the board. Just as an interesting observation: This GPS module has two MCX connectors, one on the top of the board for the antenna and one on the bottom which mates with the system board. Directly adjacent to this is a 16.368 (or thereabouts) TCXO can. It works with a standard antenna, so it looks like this is setup to work with both downconverting and standard antennas. I had to go to the Internet Archive to find the old Trimble page (http://www.trimble.com/y2kwnro/index2.htm) on Y2k/WNRO status. While this specific module wasn't listed, it didn't look encouraging. I do have a Trimble ACE III receiver which I am going to try using tonight. It is supposed to report the absolute GPS week since 06 January 1980 as an integer value and not truncated to 10 bits. Trimble says: The ACE III GPS module has been designed to handle WNRO, and there are no problems with either dates or first fix after WNRO through the year 2015. Not sure what happens after 2015... Note that due to the 16.368MHz TCXO can being right next to the GPS module, I had to modify the ACE III by changing the connector type to match the existing connector and move it to the other side of the board. I'll report back with the results. Maybe I'll get lucky for once. Paul On 06/12/2012 03:52 AM, Azelio Boriani wrote: Is the GPS unit built-in (TBolt-like) or is it a separate module? Maybe there is a firmware update for the GPS unit itself to fix the rollover problem. On Tue, Jun 12, 2012 at 5:26 AM, Ziggyzig...@pumpkinbrook.com wrote: I've recently acquired one of these, primarily to use as an alternative to (and for comparison with) my Thunderbolt. This was a DC model that was inoperative when I received it and at $225 (price from the OEM) to replace the failed DC-DC converter, I installed an AC supply. So far, so good. The unit powers up, tracks, locks the OCXO and things look generally good. I'm giving it some burn in time before I try to characterize it. However, I have a couple of issues. I did search the archives, and have contacted Symmetricom (who politely told me this unit was obsoleted 2 generations of product ago :) The menus and serial command responses do not match any version of the manual that I can find, although the Datum 9390 manual on Didier's site is pretty close on the commands. Does anyone have a manual that covers this model/firmware? This unit suffers from a GPS epoch rollover problem. This makes the date produced incorrect, and there is no way to override it, or offset it in my firmware (DT813MP) other than running it in 'freewheel' or undisciplined mode. It's my understanding that there may have been a firmware update to address this, so if you have a firmware image, or a unit with later firmware it would really be great to get a PROM copy/image. And perhaps a silly question: Is the LCD supposed to be illuminated? Because mine isn't. I haven't taken the front panel apart yet to check out the display - I've been more concerned with getting the unit operational. In the end, it's pretty usable the way it is, but the date being off irks me. I'd like to fix that if I can, and docs that match the hard/firmware would be nice. Any help would be greatly appreciated. Best regards, Paul - K9MR ___ 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] Datum/Exactime 9390-6000
I've recently acquired one of these, primarily to use as an alternative to (and for comparison with) my Thunderbolt. This was a DC model that was inoperative when I received it and at $225 (price from the OEM) to replace the failed DC-DC converter, I installed an AC supply. So far, so good. The unit powers up, tracks, locks the OCXO and things look generally good. I'm giving it some burn in time before I try to characterize it. However, I have a couple of issues. I did search the archives, and have contacted Symmetricom (who politely told me this unit was obsoleted 2 generations of product ago :) The menus and serial command responses do not match any version of the manual that I can find, although the Datum 9390 manual on Didier's site is pretty close on the commands. Does anyone have a manual that covers this model/firmware? This unit suffers from a GPS epoch rollover problem. This makes the date produced incorrect, and there is no way to override it, or offset it in my firmware (DT813MP) other than running it in 'freewheel' or undisciplined mode. It's my understanding that there may have been a firmware update to address this, so if you have a firmware image, or a unit with later firmware it would really be great to get a PROM copy/image. And perhaps a silly question: Is the LCD supposed to be illuminated? Because mine isn't. I haven't taken the front panel apart yet to check out the display - I've been more concerned with getting the unit operational. In the end, it's pretty usable the way it is, but the date being off irks me. I'd like to fix that if I can, and docs that match the hard/firmware would be nice. Any help would be greatly appreciated. Best regards, Paul - K9MR ___ 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] US Army Frequency Standard
Well, it's still probably better than nothing, even with the missing bits. It's kind of an interesting little box and the lack of a completely unencumbered version of this manual really annoyed me. So I've posted a complete PDF version on my website for those interested. It's a little hefty at 18M. The link is: http://www.pumpkinbrook.com/files/TS65-FMQ1_Manual.pdf Ziggy On Jan 24, 2012, at 7:09 PM, J. Forster wrote: Ah, thanks. I have complained to Google about that scanning issue. IMO, it's a real problem. In a few years, Google may have the only extant copy of some doc. And it will be near useless w/o the fully scanned pages. This is the third time this has come up in the last few months. Either they should do it correctly, or not at all. YMMV, -John = On 01/24/2012 11:59 PM, J. Forster wrote: Google: FMQ-1 Test Set The -24P Parts Manual w/ exploded parts ID is in many places and has a drawing of the front panel. It has no schematics. The full manual will be -15 to -45 Depot Maintenance Manual, per standard Army nomenclature. The last digit will be 5, without a following P. Google has TM 11-6625-407-14 scanned. The fold-out schematic pages isn't folded out... but you get a pretty good idea how it works from the rest of the text. The schematics is there fractioned over the pages explaining it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts 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] US Army Frequency Standard
I know it's generally bad form to reply to my own post, but if you downloaded the manual already, you may want to do it again. I found a copy of the complete schematic and updated the manual, inserting the schematic where it should be. Ziggy --- On Jan 25, 2012, at 9:48 PM, Ziggy wrote: Well, it's still probably better than nothing, even with the missing bits. It's kind of an interesting little box and the lack of a completely unencumbered version of this manual really annoyed me. So I've posted a complete PDF version on my website for those interested. It's a little hefty at 18M. The link is: http://www.pumpkinbrook.com/files/TS65-FMQ1_Manual.pdf Ziggy On Jan 24, 2012, at 7:09 PM, J. Forster wrote: Ah, thanks. I have complained to Google about that scanning issue. IMO, it's a real problem. In a few years, Google may have the only extant copy of some doc. And it will be near useless w/o the fully scanned pages. This is the third time this has come up in the last few months. Either they should do it correctly, or not at all. YMMV, -John = On 01/24/2012 11:59 PM, J. Forster wrote: Google: FMQ-1 Test Set The -24P Parts Manual w/ exploded parts ID is in many places and has a drawing of the front panel. It has no schematics. The full manual will be -15 to -45 Depot Maintenance Manual, per standard Army nomenclature. The last digit will be 5, without a following P. Google has TM 11-6625-407-14 scanned. The fold-out schematic pages isn't folded out... but you get a pretty good idea how it works from the rest of the text. The schematics is there fractioned over the pages explaining it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts 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] Vectron 217-9043 10MHz OCXO
Hijacking my own thread back here :) Thanks for tip - I did know about Skycraft, and I think there was another in the Orlando area, but I wasn't able to make the trip over that way before I had to leave town. Back on topic though, if anyone has an old catalog, or some other source of info on the old Vectron OCXO such as I mentioned, it would be most helpful. I'm not even sure if I'm running it at the right voltage. Thanks! ___ 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] Vectron 217-9043 10MHz OCXO
While in Florida on business last week, fairly close to Cape Canaveral, I stopped in at the only surplus house I could find: AstroToo in Melbourne. Poking around there, I found several Vectron 217-9043 10MHz OCXO. I could not readily find any info on this model/series at the time of purchase, but bought one anyway. Cheap entertainment no matter what the outcome :) Thing is, I still cant find any directly relevant info. Digging through the time-nuts archives, I found info on other Vectron OCXO that have a similar 7 pin connector on the bottom, but this unit has no SMA connector - only the 7 pins. The standard for these seems to be: 1 - Output 2 - Case 3 - Power -/Case 4 - Power + 5 - EFC Supply (if present) 6 - EFC Input 7 - EFC -/Case That seems to pretty much match this model, and I've noted that at 12V, there is distortion in the output, but at 15 V it looks clean. It's not quite a sine wave, but it looks reasonable as does the output level. The current starts out around 400ma and drops to 70-80ma once warmed up. So I don't think the supply voltage is too far off. The thing is, pin 5 instead of being not connected, ground or some EFC supply voltage, also has 10MHz on it at about twice the output level as pin 1, but seems quite sensitive to load. Pins 6 and 7 are apparently not connected. The pin 5 signal doesnt match any 7 pin Vectron OCXO pinouts that I can find, so I'm not sure what the story is on this unit. I'm currently running it on the bench, letting it settle in. Would have been nice if it had EFC but that doesn't seem to be the case. If anyone has any info on this series OCXO, I would much appreciate seeing it. Thanks! Paul - K9MR ___ 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] List Threading Behavior?
The other way that threads get broken is by thread 'hijacking'. If I were to hit reply to any message on this thread, change the subject and delete the body, I could write a 'new' message. Threaded clients would see that new message as part of the existing thread, but others would simply see a new message with a new subject. It's bad form to use 'reply' and change the subject. If you're going to change the subject, start with a new and blank message. Ziggy On 10/25/2011 05:38 PM, Justin Pinnix wrote: Looking at recent instances of thread-breaking tells a different story: X-Mailer: QUALCOMM Windows Eudora Version 7.1.0.9 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:7.0.1) Gecko/20110929 Thunderbird/7.0.1 User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.21) Gecko/20110830 Thunderbird/3.1.13 While these mailers are all running on Microsoft OSes, none of them are actual Microsoft products. ___ 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] Rapco 1804M - serial problems?
Actually no, it doesn't have to be the software. In my day job, I work for a company that makes terminal servers (networked serial concentrators) and have seen many times where USB/serial converters do not behave properly. I would bet that choosing a different USB/serial dongle would fix the problem. Generally speaking it seems the FTDI based units are the most dependable, but implementations vary. HTH Paul --- On Oct 18, 2011, at 1:56 PM, David J Taylor wrote: The short version: it's now OK! The long version: I dug out the old terminal, found it had no mains plug, added that, and noted it was video out. Dug out an old TV, found the remote control had corroded batteries (how often have I warned people about that!) had to dig those out and find a couple of fresh AAAs so that I could switch the TV to video input, and eventually got the terminal working. Although the terminal didn't respond to the line feed characters, it did have a display control characters mode, and that showed that the data stream was OK. Went back to the PC and noted that I had a very simple terminal emulation program supplied with one of the Delphi components I use (TComPort). Compiled that, and it displayed the data perfectly. The program is supposed to emulate VT100, and that's what I had been using on the other programs (HyperTerminal and TeraTerm Pro). Same serial settings, of course. Why those others don't work, and this very simple emulator does, is a mystery which will have to wait for another day It has to be the software, doesn't it? Too fancy a terminal emulation? Port settings incorrect (but not on two programs, surely). Answers on a five-pound note, please! Anyone with an 1804 care to try it with TeraTerm Pro or HyperTerminal? And a Sitecom USB hub/serial/parallel box. Half a day wasted, but at least with a positive result. I've let the eBay seller know. My thanks to all here who tried to help. Cheers, David -- SatSignal software - quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ 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] Thunderbolt hardware revisions
Well, if it's any help, on my rev E unit with the 'coarse' temperature chip, there is a sticker on the top (near the power connector) with a bar code, a date (3/14/05) and the Rev E designation. There's also a series of numbers that could be a serial number and some other kind of rev designator but their significance is not clear. My Rev D unit with the 'fine' temperature chip has a similar sticker dated 12/16/03. Paul - K9MR On Aug 10, 2011, at 5:55 PM, Richard W. Solomon wrote: OK, now, how old is old enough ?? Where is the units date code located ? Hopefully, the seller knows (or even cares) where to find it. 73, Dick, W1KSZ -Original Message- From: Bob Camp li...@rtty.us Sent: Aug 10, 2011 9:59 AM To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Subject: Re: [time-nuts] Thunderbolt hardware revisions Hi The real question is what's the date code on the unit? If the rev E part is old enough to have the good thermometer chip in it - that's the one to get. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of David Garnier Sent: Tuesday, August 09, 2011 10:19 PM To: time-nuts@febo.com Subject: [time-nuts] Thunderbolt hardware revisions Hi, I'm brand new to the time-nut odessy thing so please bear with me. ;-) I'm in the market to buy a used Thunderbolt, I have found a vendor that's selling used Thunderbolt receivers and states one can have the choice of PCB revisions A, B or E. Does anyone have any specific info or determined the product history of these guys? Any information would be greatly appreciated. Thanks, Dave Garnier - wb9own ___ 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] GPS Filter
The discussion got me to thinking about how we used to filter out nearby interference on amateur TV - namely by using interdigital filters. This led to a search for GPS interdigital filters which i did indeed find. See Alison Microwave website at http://www.amlant.co.uk/DetailsAD430.htm for one example of an integrated antenna/filter/preamp. (I'm sure these aren't cheap, but I haven't asked.) As for retrofitting, you could add a filter after the antenna/amplifier assembly but I might be concerned that the amplified GPS antenna is pretty wide and may have trouble with a Lightsquared transmitter nearby. There are passive antennas though, and there are in-line amps - you'd need to add the filter in between. We made these ourselves for 439 and 1296 MHz - GPS L1 isn't much above that so with some care it should be doable. The tuning can be finicky though :\ Ziggy On 03/04/2011 03:31 PM, John Ackermann N8UR wrote: Here's a measurement we did a few years ago on the HP 58535A: http://www.febo.com/pages/hp_gps_splitter/port_1_hp_58535a_two_port_amp.png John On 3/4/2011 1:31 PM, Bob Camp wrote: Hi Ok, now it's pretty obvious the RF world near your GPS will be changing a *lot* in the near future. Lightsquared and a bunch of similar outfits will be camping out right next door with very high power gear. They will be running 1.5KW from somewhere in town. GPS is running 30 watts from off planet. Has anybody tossed the various HP / Symmetricom GPS splitters on a network analyzer? If so, what do the filters in them look like? I probably should corner the market on these things before asking a question like that. The new neighbors will be at 1525 to 1559 MHz. GPS L1 is at 1575.42 MHz. That's what we are using for timing. L2 is down at 1227.5, right now it's mainly military use. Obviously these guys are a bigger deal for civilians than the military. So the question is - do the built in splitter filters have any real rejection 15 to 50 MHz off of center? Probably worth checking. It would be a pleasant surprise if they turned out to be useful. Bob ___ 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] Lightsquared and a little math
Wow - yet another on-topic time-nuts discussion... Really guys? I mean REALLY? On Feb 4, 2011, at 8:30 AM, William H. Fite wrote: True enough. And it certainly was not the left that condoned--or ever would condone--leaving the stadium lights on while turning off power to hospitals and nursing homes. Which didn't happen, by the way, but it makes a fantastic tale. And power * did* roll off for virtually all non life-critical applications. On Fri, Feb 4, 2011 at 2:32 AM, li...@lazygranch.com wrote: Five out of nine people believe money is free speech and a corporation is a person. Well five conservative judges. ;-) -Original Message- From: Perry Sandeen sandee...@yahoo.com Sender: time-nuts-boun...@febo.com Date: Thu, 3 Feb 2011 22:45:05 To: time-nuts-requ...@febo.comtime-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: [time-nuts] Lightsquared and a little math List, Wrote The nationwide LightSquared network, consisting of approximately 40,000 cellular base stations, will cover 92 percent of the U.S. population by 2015 You can make book the missing 8 percent will be areas that exclude the farmers and ranchers who provide our food but the left will make sure the always “financially challenged” in the slums will have it and probably for free. The proof? In every state in the US there is something called a universal service fee on your phone bill. This is usually 35 to 45 cents. It is not optional. The purpose of that fee is modeled after the postal system that charges you the same amount whether one sends a letter 2 miles or 2,000 miles so that everyone can economically communicate. By law the phone companies are given that money to provide the rural areas with the same services that are offered in urban areas. This includes broadband DSL and TV services. It has never happened and probably won’t as we seem to have the best politicians money can buy. I’m a conservative and I have lived in two rural areas now and the story is the same. ATT continues to send me glowing adverts for bundled phone service only. When I lived in a large town they came door to door trying to sign people up for broadband and the regularly sent glowing adverts in my phone bill to sign up for bundled phone, DSL broadband, and TV. This explains while they kept the lights on continuously at the Dallas Cowboy stadium for the superbowel, they had 15 minute rolling blackouts to all the area hospitals, nursing homes and elder care facilities where residents rely on continued electrical service for their oxygen concentrators and assisted breathing devices. Regards, Perrier ___ 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] Thunderbolt 10MHz
There is an EEPROM that can be used to store parameter such as the initial DAC voltage, position, etc. but it's not automatic. Have you explicitly saved the position (or auto stored it) after the survey is complete? If you don't do this then it will have to do a survey on every startup and that takes a bit. Ziggy On 11/6/2010 8:14 AM, David Hopkins wrote: Gentlemen, A question on the Thunderbolt. Lately every time I turn the Thunderbolt off and then on again I have to do a cold reset. It then takes about 10-20 minutes before it is fully operational again. This is most unsatisfactory. Its almost as if its lost most of its settings. Is there some internal memory backup device that dies with age? Any suggestions would be appreciated. David David G. Hopkins (VK4ZF) CAPALABA QLD AUSTRALIA 27.32.38S 153.12.03E QG62OL Skype :- davhop ___ 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] Odd Lady Heather graph
I don't know if embedded images will make it through to the list, but can someone explain the behavior indicated in this graph? This is from an auction and it doesn't look at all like other graphs that I've seen. It's only for a 12 min span, but others with a short span aren't similar. If the included graph doesn't make it to the list, please take a look at the auction (150508234942). I'd like to understand more of what I am am seeing there. Thanks! Ziggy Please wait Image not available ___ 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] Odd Lady Heather graph
I did note that it was the temp sensor, but the behavior was clearly different. I guess my earlier search terms weren't good enough to reveal this info about the sensor differences in the T'bolts. I've done some further digging and now have the scoop on these DS1620 changes, etc. Other than pretty graphs, it looks like the difference between units using one vs. the other is a (relatively) minor difference in pps jitter. Also that for those interested enough, there have been plenty of folks that have swapped the sensor. Thanks! Ziggy On 10/23/2010 3:31 PM, Bob Camp wrote: Hi If you look at the fine print on the yellow graph, it's running right at the limit of the bad temp sensor. What you are seeing is normal stepping / averaging on the low resolution sensor. Bob On Oct 23, 2010, at 3:28 PM, Magnus Danielson wrote: Hi Ziggy, On 10/23/2010 09:05 PM, Ziggy wrote: I don't know if embedded images will make it through to the list, but can someone explain the behavior indicated in this graph? This is from an auction and it doesn't look at all like other graphs that I've seen. It's only for a 12 min span, but others with a short span aren't similar. If the included graph doesn't make it to the list, please take a look at the auction (150508234942). I'd like to understand more of what I am am seeing there. I assume you refer to the yellow curve... Isn't that the average from the temp-sensor, being the modern coarse-stepped variant as things heats up it looks like the step-response of a one pole low-pass filter. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts 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] GPSDO Comparisons
I did some searching (perhaps ineffectively) of the archives, looking for some discussion of the merits of the different GPSDO products that we commonly see on auction sites. I've seen some discussions of individual models, but nothing that really discusses the differences, and why one unit may be superior to another. I'm a newcomer, so please be patient with my silly questions :) For example, what are the relative merits of the HP units? There are different vintages HP Z3801A, Z3805A, Z3815A, etc. and datasheets are available, but what difference is there when using the output from these different models? For example, the Z3801A has a 6 channel GPS receiver. The Samsung/Symmetricom Z3805A we see out there has a 16 channel receiver. What is the difference when it comes to practical usage of these two different units? Does tracking 10 or 12 satellites provide a benefit over tracking 6? Then there are the different manufacturers. There are the HP units, the Alcatel-Lucent units (also of varying vintage), Trimble Thunderbolts, and others. Again, when it comes to practical usage is there any difference between these? Is there any value in paying the premium for a Z3805A over a Thunderbolt? (Above the plug and play aspects.) I can get an older ALU unit with both GPSDO and Ru units for $100. How am I hurting myself with that purchase? There is certainly more public information available for some vendors and models than others. The software like Lady Heather or GPS Control provide a lot of information, and for the less popular units there is no such software option. Under what circumstances would that be a handicap? I freely admit I'm ignorant, but I'm not thin skinned. I'm just not aware yet of the factors to be considered when answering the questions above. Any comments would be appreciated. Thanks Paul ___ 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.
