Re: [time-nuts] GPS interference and history...
In message 4f0fc1aa.5070...@earthlink.net, Jim Lux writes: On 6/9/11 1:30 PM, Javier Herrero wrote: I don't think it is feasible... for a cooling reason :) Soviet had an entire series of spy-satellits powered by reactors, one of them is still leaking droplets/pellets of sodium from the cooling system creating quite a mess. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] Z3801A's
b...@shinji.net said: My question is this... What is the current market value on working and tested Z3801A's? Feed Z3801A to ebay and see what you find. I see one at $1K, and 2 with power supply and antenna and cables at $480 and $499. (Read the fine print, YMMV...) On the other hand, ebay has a Thunderbolt for $250. There was one for $110 a short while ago. So my estimate for a Z3801A is ballpark of $250. Maybe more if you are willing to wait longer, less if you need to unload them quickly. - Does anybody know what Z3801A has been upgraded by us, which the feature is the same as 58503A. really means? -- 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.
[time-nuts] power for Rb
Just ordered power supplies for the Rb units, ebay #280439877318 $9.95, free shipping, 15v 3 A, plenty of headroom. Meant for Toshiba and other laptops. Ought to work just fine. Don -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] Lady Heather S/W
I can't speak for all of them, but I had a NTPX26AB-06 and that worked with the Trimble software, but not with Lady Heather. Regards, Pete Bell On Jan 13, 2012 1:47 PM, VK3YV vk...@internode.on.net wrote: Hi all, can anyone tell me whether Lady Heather S/W is compatible with the ex Trimble CDMA 10 Mhz reference units that run with the Thunderbolt S/W ok. Many thanks, Don ...VK3YV __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://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] Line Voltage
albertson.ch...@gmail.com said: You don't need to use the audio interface to monitor frequency. Use the PPS interface. it will time stamp each positive slope zero crossing. So you get 60 log file entries per second. Sounds like a lot but not really given the size of modern disks. I've been collecting 60Hz data using a Linux PPS hack since last July. http://www.megapathdsl.net/~hmurray/time-nuts/60Hz/60Hz-Jul11-12.png The reason I'm interested in the audio data is to be able to investigate what happens around a glitch. -- Actually, the size of the log files is interesting. Mostly, I agree about the size of modern disks. (Moore's law is great.) But there are limits. I'm interested in collecting data for many years. If I'm lucky, the cost of disks will shrink faster than I find new sources of data to collect. For the 60 Hz stuff, I'm writing a line of text to the log file every 10 seconds. With the format I picked, that's 1/2 megabyte/day or 1/3 gigabyte per year. If I blindly started logging every cycle at 60 Hz, that would be 600x as much data, 200 gigabytes per year. That no longer fits under the modern disks are big umbrella. (It might work, but it's not in the noise.) I could pick up a factor of 2 or 3 by tweaking the ASCII text format. I could pick up another factor of two by converting to binary and another factor of 2 (maybe 4) by some simple compression hacks. The bottom line is that, yes, logging every cycle at 60 Hz is not unreasonable but I think it's just over the edge of no-brainer - just do it. -- 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] EF-5680A Breakout board
On Thu, 12 Jan 2012 18:42:57 -0500 Chase Turner ke4...@gmail.com wrote: How much cheaper would you be able to manufacture the board and send them along, Attila? Would it be cheaper than 15 AUD? That highly depends on the specs of the PCB and the production size. Guestimating it's a 2.5x10cm, dual sided PCB and using PCB-pools online calculator, i get below 12EUR (~15AUD) per piece at a production size of 15. I guess if you produce it in the US, you can get cheaper than that (electronic production in europe is damn expensive). Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ 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] EF-5680A Breakout board
On Fri, 13 Jan 2012 00:20:08 + gonzo . cadbl...@hotmail.com wrote: your most welcome to the original CAD files (you can then do any mods that suit your purpose). The design was done using the free version of Eagle, so anyone can have a go. If you could send them to me, i would very much appreciate it. As for making it cheaper, your welcome to try. I hope I'm covering my costs, but I'm certainly not making a profit. I doubt i can produce them much cheaper than you. Unless you production is done in a low-wage country, the costs are +/-20% the same. What i'd aim to reduce is the shipping costs, which is quite substantial if you are shipping something from australia to europe. Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ 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] EF-5680A Breakout board
On Thu, 12 Jan 2012 19:21:40 -0800 Chris Albertson albertson.ch...@gmail.com wrote: futerlec can build 20 of the above PCBs for US$99, that's $5 each. plus shipping. And all 20 have to ship to the same address. Futurlec is an Australian company but mostly run in Thailand they have offices in US, AU, UK and asia. They can also stuff the boards and supply parts. They are my #1 parts source but have limited range so I have to go to the other places for the more rare items. Just for curiosity I got a price for 10,000 boards. It drops to $1.56 each. $2.16 for 100. But I'd bet 20 is the upper limit. lol.. if you were going to make 10k, it would be worth it to let them produce, including assembly, in far east. I guess then we could get below 5USD/piece for fully assembled devices. :-) But still.. if there would be enough interest in fully assembled devices, a production run of those shouldn't be too difficult. But assembly isn't really worth it below lot sizes 50-100 pieces as the NRE is just too high. Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ 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] Temperature and signal amp for 'Bay FE-5680A?
On Thu, 12 Jan 2012 00:50:35 +1300 Bruce Griffiths bruce.griffi...@xtra.co.nz wrote: Thats certainly not the case in the FS730C, the risetime isnt appreciably affected by the small (4R7) damping resistor in series with Vcc. Adding a series damping resistor in series with the output is insufficient to suppress ringing. How about using a ferit bead into the power supply instead of a resistor? I'm thinking about something like a BLM18. The DC resistance is much lower while HF resistance is much higher. Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ 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] FE-5680A tear down on Youtube
Hi, This is my first post to the list, but I have been a long time reader and found it extremely interesting and informative. I think you guys might find this interesting.. Its a video of a FE-5680A being dissembled on Youtube. I had noticed that within hours of the video being published 14 of the cheaper 5680A's were sold! as the producer of the video (not me) has over 14,800 subscribers, my thoughts are that this may have some effect on the used FE-5680A price or even advanced depletion of the stock.. I'm glad mines on the boat already. The tear down: http://www.youtube.com/watch?v=FRdGsSu5Nec The theory of operation: http://www.youtube.com/watch?v=I55uLRRvLCU Sam. ___ 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] Temperature and signal amp for 'Bay FE-5680A?
Attila Kinali wrote: On Thu, 12 Jan 2012 00:50:35 +1300 Bruce Griffithsbruce.griffi...@xtra.co.nz wrote: Thats certainly not the case in the FS730C, the risetime isnt appreciably affected by the small (4R7) damping resistor in series with Vcc. Adding a series damping resistor in series with the output is insufficient to suppress ringing. How about using a ferit bead into the power supply instead of a resistor? I'm thinking about something like a BLM18. The DC resistance is much lower while HF resistance is much higher. Attila Kinali It may be useful if the ferrite bead parameters are just right. However the bead HF resistance will increase the high frequency output impedance in the high state which will adversely affect the high frequency source impedance of the line driver. Whereas a resistor increases the high state output impedance in a more predictable way that can be easily compensated for particulalrly if a similar resistor were used in series with the ground lead. 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] Lady Heather for a noob
El 13/01/2012 04:57, brent evers escribió: Hijacked thread. Yes - this would be great to see done on a linux machine. I don't know that much about LH, but something done cross platform (PyQt or such - could make binaries for win, linux, and mac) in a server/client config would be great. I don't know much about NTP other than pointing machines to NTP servers for time, but having the server side provide also be an NTP server would be the cats ass for me. Pretty big wish list for someone who can't write code out of a wet paper bag huh? It would be nice, but if no graphic i/f is used for the server side, I think it would be better to implement it in standard C instead of PyQt, for portability reasons, so the server could be easily rebuilt for running in a non-PC class embedded linux computer (like those using ARM) For providing ntp, probably the best way is to use ntp :) As far as I remember, since I've not played around it since some time, the LinuxPPS driver is implemented as a character driver, so several applications can read it, and as other has pointed, ntp i/f to the GPS can be implemented using shmem. ntp can also be recompiled for running in almost anything (I've put it into work both in Nios-II uClinux-MMU and Blackfin uClinux-nonMMU, also taking time from an M12 using Linux-PPS) Best regards, Javier ___ 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] Z3801A's
I bougth one, and it seems like they have replaced the firmware with the one from 58503A. When sending *IDN to it, it responds with HP 58503A. Thomas. 2012/1/13 Hal Murray hmur...@megapathdsl.net - Does anybody know what Z3801A has been upgraded by us, which the feature is the same as 58503A. really means? ___ 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-5680A Breakout board
Hi Attila, yes, I'm certainly getting the boards made where production is cheap. Other things seem to be cheap there too; like used Rb Osc! I'm paying just under $3 per board (double sided, plated through, solder mask both sides, silk screen both sides). If it wasn't for that, I wouldn't be able to sell them for $10 with components. The first one I sent to the UK was slim enough to go as a letter weighing under 50g - I'm hoping the rest will too! The dimensions of the board are: 88mm x 22mm - about the same as the end view of the FE-5680a. I've sent you the CAD files so you can have a play. cheers, ian From: Attila Kinali att...@kinali.ch To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] EF-5680A Breakout board Message-ID: 20120113094719.676e47c8.att...@kinali.ch Content-Type: text/plain; charset=US-ASCII On Thu, 12 Jan 2012 18:42:57 -0500 Chase Turner ke4...@gmail.com wrote: How much cheaper would you be able to manufacture the board and send them along, Attila? Would it be cheaper than 15 AUD? That highly depends on the specs of the PCB and the production size. Guestimating it's a 2.5x10cm, dual sided PCB and using PCB-pools online calculator, i get below 12EUR (~15AUD) per piece at a production size of 15. I guess if you produce it in the US, you can get cheaper than that (electronic production in europe is damn expensive). Attila Kinali -- -- Date: Fri, 13 Jan 2012 09:50:42 +0100 From: Attila Kinali att...@kinali.ch To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] EF-5680A Breakout board On Fri, 13 Jan 2012 00:20:08 + gonzo . cadbl...@hotmail.com wrote: your most welcome to the original CAD files (you can then do any mods that suit your purpose). The design was done using the free version of Eagle, so anyone can have a go. If you could send them to me, i would very much appreciate it. As for making it cheaper, you'r welcome to try. I hope I'm covering my costs, but I'm certainly not making a profit. I doubt i can produce them much cheaper than you. Unless you production is done in a low-wage country, the costs are +/-20% the same. What i'd aim to reduce is the shipping costs, which is quite substantial if you are shipping something from australia to europe. Attila Kinali -- ___ 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-5680A Mechanical Question
What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren In a message dated 1/12/2012 12:20:15 P.M. Eastern Standard Time, li...@rtty.us writes: Hi I think it would be worth the effort to try dithering the DDS commands into the Rb while measuring ADEV. You *might* find that you can do it with little or no impact on the unit's stability. If so it takes out some modification effort and should make the controller cheaper. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Thursday, January 12, 2012 10:43 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question Bringing out the C field in my estimation does not effect long or short term. External magnetic field I think is a joke. An other option is a loop that generates a tuning word for the DDS but that means your steps are 7 E-13. Bert Kehren In a message dated 1/12/2012 10:34:10 A.M. Eastern Standard Time, davidwh...@gmail.com writes: I was more interested in the technical details of how to adjust the output of a RbO without sacrificing the short and long term stability. I have seen a few designs that used a DDS to generate the 10 MHz output which lends itself to this but they all suffer from DDS and tuning noise. I see now that the RbO can be adjusted with an external magnetic field. On Thu, 12 Jan 2012 07:34:44 -0600, J. L. Trantham jlt...@att.net wrote: David, I have been following discussions on the list about a GPSDRbO for a year or so. Some interesting challenges and probably best implemented in a 'stable' environment rather than portable operation but as best I can tell, it would require a very stable and good antenna location, stable and clean power, and I was thinking of using something like an LPRO-101 with an Ext C Field input, a Shera type controller, and a GPS timing receiver, though, I suspect there are likely to be some 'multi-tasking' receivers out there that will look at several sources including GPS, GLOSNASS, etc. While the project might be fun, for portable work, it is likely far easier and probably just as good (almost), to use a Tbolt. In any event, something to think about for the future. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of David Sent: Wednesday, January 11, 2012 11:12 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question How would a GPSDRbO work? Phase lock the DDS output to the GPS? Phase lock a VCXO to the GPS and then phase lock to the RbO on loss of GPS lock? On Wed, 11 Jan 2012 22:55:58 -0600, J. L. Trantham jlt...@att.net wrote: Bill, Brian, Bill, and Peter, Thanks for the info. All I need now is a 'project' to incorporate the unit into. In the back of my mind, I have the thought of a 'box' that will be battery powered or 110 VAC powered (perhaps with an internal SLA battery) and include a GPSDO and Rb unit (possibly a GPSDRbO) for the purpose of a 'reference' for portable operation in the microwave regions. ___ 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 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] EF-5680A Breakout board (Attila Kinali)
From: Attila Kinali att...@kinali.ch That highly depends on the specs of the PCB and the production size. Guestimating it's a 2.5x10cm, dual sided PCB and using PCB-pools online calculator, i get below 12EUR (~15AUD) per piece at a production size of 15. For small quantities I use PCBCART (http://www.pcbcart.com)... They work very well and the price is right: please take care they ask for tooling costs on the first order (not added on the subsequent orders). They have a price calculator on their web site (20 pieces 25x100mm = 2.29 euros/ea + one time tooling) _ Elio. ___ 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-5680A arrived
The 15 volts comes from an old Toshiba laptop ps. The 5 volts is from another switcher, similar to the famous Meanwell. http://www.omen.com/ham/gpsd.html The 15 volts seems fairly clean on my 2712. My Racal-Dana 1992 does emit a signal on 10 MHz. On 01/12/2012 03:40 AM, Javier Herrero wrote: Hello, What kind of power supply are you using for it? If a switching one, perhaps this is the origin. Regards, Javier, EA1CRB El 12/01/2012 11:39, Chuck Forsberg WA7KGX N2469R escribió: I received my Ebay Tek 2712 spectrum analyzer Monday and I have been throwing software to read its data via GPIB. Here is a spectrum I got connecting the Rb 10 MHz to the 2712. Nice little spurs. I don't see anything to account for these anywhere else. The 2712 is a big step up from Ham radio fish finders and I'm still learning things about the 2712. It would be nice to have original easy to read printed manuals and/or a high quality PDF. The black and white (no greyscale) PDFs on the internet are hard on the eyes and not searchable. ___ 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. -- Chuck Forsberg WA7KGX n2469r...@omen.comwww.omen.com Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc The High Reliability Software 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 attachment: rb7.gif___ 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-5680A Mechanical Question
did a preliminary layout and priced it with expressPCB and in 30 quantity the board would cost $ 5 !!! Any expert willing to volunteer.to do the loop? Bert Kehren In a message dated 1/13/2012 6:20:25 A.M. Eastern Standard Time, ewkeh...@aol.com writes: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren In a message dated 1/12/2012 12:20:15 P.M. Eastern Standard Time, li...@rtty.us writes: Hi I think it would be worth the effort to try dithering the DDS commands into the Rb while measuring ADEV. You *might* find that you can do it with little or no impact on the unit's stability. If so it takes out some modification effort and should make the controller cheaper. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Thursday, January 12, 2012 10:43 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question Bringing out the C field in my estimation does not effect long or short term. External magnetic field I think is a joke. An other option is a loop that generates a tuning word for the DDS but that means your steps are 7 E-13. Bert Kehren In a message dated 1/12/2012 10:34:10 A.M. Eastern Standard Time, davidwh...@gmail.com writes: I was more interested in the technical details of how to adjust the output of a RbO without sacrificing the short and long term stability. I have seen a few designs that used a DDS to generate the 10 MHz output which lends itself to this but they all suffer from DDS and tuning noise. I see now that the RbO can be adjusted with an external magnetic field. On Thu, 12 Jan 2012 07:34:44 -0600, J. L. Tranthamjlt...@att.net wrote: David, I have been following discussions on the list about a GPSDRbO for a year or so. Some interesting challenges and probably best implemented in a 'stable' environment rather than portable operation but as best I can tell, it would require a very stable and good antenna location, stable and clean power, and I was thinking of using something like an LPRO-101 with an Ext C Field input, a Shera type controller, and a GPS timing receiver, though, I suspect there are likely to be some 'multi-tasking' receivers out there that will look at several sources including GPS, GLOSNASS, etc. While the project might be fun, for portable work, it is likely far easier and probably just as good (almost), to use a Tbolt. In any event, something to think about for the future. Joe -OriginalMessage- From: time-nuts-boun...@febo.com[mailto:time-nuts-boun...@febo.com] On Behalf Of David Sent: Wednesday, January 11, 2012 11:12 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question How would a GPSDRbO work? Phase lock the DDS output to the GPS? Phase lock a VCXO to the GPS and then phase lock to the RbO on loss of GPS lock? On Wed, 11 Jan 2012 22:55:58 -0600, J. L. Trantham jlt...@att.net wrote: Bill, Brian, Bill, and Peter, Thanks for the info. All I need now is a 'project' to incorporate the unit into. In the back of my mind, I have the thought of a 'box' that will be battery powered or 110 VAC powered (perhaps with an internal SLA battery) and include a GPSDO and Rb unit (possibly a GPSDRbO) for the purpose of a 'reference' for portable operation in themicrowave regions. ___ time-nutsmailing list -- time-nuts@febo.com To unsubscribe, goto https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts andfollow the instructionsthere. ___ time-nutsmailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructionsthere. ___ time-nutsmailing 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] Austron 1150
I am looking at using a Austron 1150 in a Tbolt has any one done it or is there any one out there that has experience with the EFC. I want to proceed carefully before playing with the EFC. Also one of the 1150's says power 12-28 Volt, does any one have experience with that. Thanks Bert Kehren ___ 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 interference and history...
On 6/10/11 7:01 PM, Hal Murray wrote: li...@rtty.us said: There's an enormous amount of gear out there that gets timing off of GPS. That's an interesting claim. Does anybody have any data on the usage of GPS for timing? I assume there is one in every cell tower and one in every 911 call center. Are there other large categories of users? GPS is pretty ubiquitous as a time source for data loggers in the field, things like traffic signals, etc. There's real value in an inexpensive little box that makes sure you don't have to set the clock, even if the clock accuracy requirement is something like 1 minute. What would it cost to replace all of it? If you wanted to do something like that, what would it cover? How about people like us running old recycled gear? (Z3801A, ThunderBolt, ...) A fortune, quite literally I think I saw one last week. It was on a river level measuring station on the Sacramento River. It was a small block building. There was an antenna pointing up into the sky. I assume there is a satellite up there. There was also a small (~3 inch dia) hemisphere antenna. I assume it was GPS. (They had power going into the building (no solar panels) so it should have been simple to get a phone line too.) Not necessarily. And it's not cheap. Don't forget that you can't run power and phone in the same conduit, cable, etc. So basically you're doubling the physical plant installation costs to bring in phone, just for the labor to bring it from the nearest point of presence. Especially in rural farm kinds of areas, power is more pervaisve than phone (gotta run irrigation pumps, etc.) Adding a $100-200 GPS receiver (we're not talking GPSDO with OCXO here..) is probably cheaper than running ANY length of phone wires: just for the termination costs. I suppose one could use some sort of GPRS cellular service and get time, but then you're on the hook for a monthly subscription fee, etc. cheap L1 only GPS is a great solution. Apply power, wait, you've got accurate time. No need to have someone visit periodically and check to see if the clock needs to be reset, etc. I'm not sure why they need GPS at the recording house. They know where it is so timing is the only use I can think of. But they could also get that at the receiving end. Millisecond accuracy isn't helpful. Second level accuracy might be interesting if something breaks and you want to know when the wave got to downstream stations. The risetime is probably over a second. You're right, they don't need milliseconds, nor do they need seconds, probably. There's really no other convenient way to get time to the nearest minute that is as reliable and cheap as GPS. Think about it... WWVB? WWV? Vertical pointing sun sensor? ___ 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 interference and history...
Any large IT organization has multiple stratum 1 GPS based timing receivers. The public key for our internal routing updates is the time. No time and the routing would break. We route ~10+ Tb/hr in the 8am-5pm business day. That would be noticed by our users... On one building on our campus (College of Engineering ~1/4 mile long building ) I counted 14 mushroom antennas, I see other patch antennas on windows... Jim Cotton On 1/13/12 9:29 AM, Jim Lux wrote: On 6/10/11 7:01 PM, Hal Murray wrote: li...@rtty.us said: There's an enormous amount of gear out there that gets timing off of GPS. That's an interesting claim. Does anybody have any data on the usage of GPS for timing? I assume there is one in every cell tower and one in every 911 call center. Are there other large categories of users? GPS is pretty ubiquitous as a time source for data loggers in the field, things like traffic signals, etc. There's real value in an inexpensive little box that makes sure you don't have to set the clock, even if the clock accuracy requirement is something like 1 minute. What would it cost to replace all of it? If you wanted to do something like that, what would it cover? How about people like us running old recycled gear? (Z3801A, ThunderBolt, ...) A fortune, quite literally I think I saw one last week. It was on a river level measuring station on the Sacramento River. It was a small block building. There was an antenna pointing up into the sky. I assume there is a satellite up there. There was also a small (~3 inch dia) hemisphere antenna. I assume it was GPS. (They had power going into the building (no solar panels) so it should have been simple to get a phone line too.) Not necessarily. And it's not cheap. Don't forget that you can't run power and phone in the same conduit, cable, etc. So basically you're doubling the physical plant installation costs to bring in phone, just for the labor to bring it from the nearest point of presence. Especially in rural farm kinds of areas, power is more pervaisve than phone (gotta run irrigation pumps, etc.) Adding a $100-200 GPS receiver (we're not talking GPSDO with OCXO here..) is probably cheaper than running ANY length of phone wires: just for the termination costs. I suppose one could use some sort of GPRS cellular service and get time, but then you're on the hook for a monthly subscription fee, etc. cheap L1 only GPS is a great solution. Apply power, wait, you've got accurate time. No need to have someone visit periodically and check to see if the clock needs to be reset, etc. I'm not sure why they need GPS at the recording house. They know where it is so timing is the only use I can think of. But they could also get that at the receiving end. Millisecond accuracy isn't helpful. Second level accuracy might be interesting if something breaks and you want to know when the wave got to downstream stations. The risetime is probably over a second. You're right, they don't need milliseconds, nor do they need seconds, probably. There's really no other convenient way to get time to the nearest minute that is as reliable and cheap as GPS. Think about it... WWVB? WWV? Vertical pointing sun sensor? ___ 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 interference and history...
When you are thinking about replacing GPS receivers, don't forget about every police car, ambulance, fire truck and most of the tractor trailer's in the US...The latter don't need timing down to the second, but the first three use it to well under a minute. One of the first things you learn when on an ambulance crew is what lump on the roof to wrap the aluminum foil over when you are going to park the rig after that run of 5 middle of the night calls and go to sleep. ;) Some day I'll get the laptops in the rigs to sync up with the GPS directly rather than using NTP. ;) We probably should be using it to drive the time code in the video recorders...H. Bob On Fri, Jan 13, 2012 at 9:29 AM, Jim Lux jim...@earthlink.net wrote: On 6/10/11 7:01 PM, Hal Murray wrote: li...@rtty.us said: There's an enormous amount of gear out there that gets timing off of GPS. That's an interesting claim. Does anybody have any data on the usage of GPS for timing? I assume there is one in every cell tower and one in every 911 call center. Are there other large categories of users? GPS is pretty ubiquitous as a time source for data loggers in the field, things like traffic signals, etc. There's real value in an inexpensive little box that makes sure you don't have to set the clock, even if the clock accuracy requirement is something like 1 minute. What would it cost to replace all of it? If you wanted to do something like that, what would it cover? How about people like us running old recycled gear? (Z3801A, ThunderBolt, ...) A fortune, quite literally I think I saw one last week. It was on a river level measuring station on the Sacramento River. It was a small block building. There was an antenna pointing up into the sky. I assume there is a satellite up there. There was also a small (~3 inch dia) hemisphere antenna. I assume it was GPS. (They had power going into the building (no solar panels) so it should have been simple to get a phone line too.) Not necessarily. And it's not cheap. Don't forget that you can't run power and phone in the same conduit, cable, etc. So basically you're doubling the physical plant installation costs to bring in phone, just for the labor to bring it from the nearest point of presence. Especially in rural farm kinds of areas, power is more pervaisve than phone (gotta run irrigation pumps, etc.) Adding a $100-200 GPS receiver (we're not talking GPSDO with OCXO here..) is probably cheaper than running ANY length of phone wires: just for the termination costs. I suppose one could use some sort of GPRS cellular service and get time, but then you're on the hook for a monthly subscription fee, etc. cheap L1 only GPS is a great solution. Apply power, wait, you've got accurate time. No need to have someone visit periodically and check to see if the clock needs to be reset, etc. I'm not sure why they need GPS at the recording house. They know where it is so timing is the only use I can think of. But they could also get that at the receiving end. Millisecond accuracy isn't helpful. Second level accuracy might be interesting if something breaks and you want to know when the wave got to downstream stations. The risetime is probably over a second. You're right, they don't need milliseconds, nor do they need seconds, probably. There's really no other convenient way to get time to the nearest minute that is as reliable and cheap as GPS. Think about it... WWVB? WWV? Vertical pointing sun sensor? __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://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] sorry about the necro-post..
I haven't figured why yet, but I think it's something with an old post inadvertently getting marked unread and since I have tbird set up for viewing threads with unread, it looked like it had just come in (and, of course, who looks at the time posted?) Maybe I'll go back to simple chronological, rather than this newfangled threaded viewing... We now return to your regular, monotonically increasing, time sequenced mailing list. Sorry all. (and even more egregious.. it was somewhat off topic.. I am humbled) ___ 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] Z3801A's
Kind of scratching my head here. I have a 3801, great box. But I also have to say that since it can't run lady heather I do not see the value epay wants. Before everything spun up as they always do the 3801 was a $200 box and slightly less. I do not know why but I purchased mine on epay and I want to say $175. So if you have to have one then $500s fine, but it breaks my simple logic in value. If I had $200 I would certainly be considering the Tbolt. What would I pay $75, since its a backup that I have lived 10 years without. Just my crazy way of thinking. Regards Paul WB8TSL On Fri, Jan 13, 2012 at 4:46 AM, Thomas S. Knutsen la3...@gmail.com wrote: I bougth one, and it seems like they have replaced the firmware with the one from 58503A. When sending *IDN to it, it responds with HP 58503A. Thomas. 2012/1/13 Hal Murray hmur...@megapathdsl.net - Does anybody know what Z3801A has been upgraded by us, which the feature is the same as 58503A. really means? ___ 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] sorry about the necro-post..
This and John Fosters response. I haven't laughed so much in I can't remember when. Thanks, Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Jim Lux Sent: Friday, January 13, 2012 9:02 AM To: Discussion of precise time and frequency measurement Subject: [time-nuts] sorry about the necro-post.. I haven't figured why yet, but I think it's something with an old post inadvertently getting marked unread and since I have tbird set up for viewing threads with unread, it looked like it had just come in (and, of course, who looks at the time posted?) Maybe I'll go back to simple chronological, rather than this newfangled threaded viewing... We now return to your regular, monotonically increasing, time sequenced mailing list. Sorry all. (and even more egregious.. it was somewhat off topic.. I am humbled) ___ 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] FE5680a arrived in boston $38 shipping included
Well mine arrived Monday so about 3 weeks. Its the one without the useless to me oscillator. But I found it quite funny. It came bubble wrapped, cheap shipper mail as expected and commented in the list. But I have something far more valuable now then the oscillator. A teddy bear and 7805 regulator for the magical 5 V. There you go that 7508 was really protected by the teddy bear. Or They are dumping access teddy bears on the world market. ;-) Will fire up the unit tonight and see if I have the 2 sec pulse etc. Regards Paul WB8TSL ___ 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-5680A Mechanical Question
On Fri, Jan 13, 2012 at 3:19 AM, ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one. Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage. Many already have audio input with 24-bit ADC chips. Later you can move the C code from the PC pretty much directly to an AVR. PICs typically use assembly language, that is harder and limits the number of people who can contribute changes to the code. But you can start with a PC, maybe running Linux or BSD. 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.
[time-nuts] Storage locker cleanout
To anyone in the Minneapolis area: Collected a lot of stuff from eBay during the last decade, to keep me busy in retirement. Turned out that need never arose. Now I can't afford to keep an 8x8 storage locker anymore, so it must be empty by the end of this month. There are many rack-mount time code generators, most by Datum. They're 1, 2, and 3 rack units high. All have 5 and +/- 12 or 15 VDC compact power supplies. The 3 and 5U units have 1 MHz crystals in ovens. All have 9 digit led displays, and all speak IRIG. Thumbwheels are used to preset the digits. None have GPS receivers. There are time instruments by HP, as well as Tek scopes and other fine old vacuum tube items. All of what's in the locker is free for pickup at 6200 W Old Shakopee Road in Bloomington, MN. Things that are not free include a pair of Z3801As with HP cone antennas and 50 feet of RG8U cable and a Ratelco 48 VDC positive ground power supply. There's a 2 KVA sine wave Liebert computer UPS that requires eight 12V batteries, as large as you like. Then there's three HP 3335 synthesizers (200 Hz to 80 MHz) that I need to test. Two of them work, IIRC. One has Telco outputs. Pictures available from b...@iaxs.net, or call 952 835-6840. Bill Hawkins ___ 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-5680A Mechanical Question
On Fri, Jan 13, 2012 at 4:48 AM, ewkeh...@aol.com wrote: did a preliminary layout and priced it with expressPCB and in 30 quantity the board would cost $ 5 !!! Any expert willing to volunteer.to do the loop? Bert Kehren If the board uses AVR, has in-circuit programming and the ability to do in-circuit debug yes. Otherwise much time is wasted do the burn-test-gues what's wrong-burn-test. 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] FE-5680A Mechanical Question
On 1/13/12 8:15 AM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 3:19 AM,ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one. Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage. Many already have audio input with 24-bit ADC chips. But those audio inputs are almost always AC coupled. Bringing up a question: Does anyone know of a cheap ($20ish) USB voltage sensor (16 bits or better, ideally).. I can see one of those Atmel USB capable micros (like the one on the Arduino Uno) hooked to a dual slope or successive approximation ADC. There seem to be an amazing number of times that I want something like that. The DATAQ $29 widget is only 10 bits, unfortunately. A USB interface DMM would work nicely, but I haven't found one that's in the under $50 price 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] FE-5680A Mechanical Question
I recommend we talk. I am flexible, using 24 bit A/D will blow the budget and there is no way to do it for the cost goal. Bert In a message dated 1/13/2012 11:16:38 A.M. Eastern Standard Time, albertson.ch...@gmail.com writes: On Fri, Jan 13, 2012 at 3:19 AM, ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one. Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage. Many already have audio input with 24-bit ADC chips. Later you can move the C code from the PC pretty much directly to an AVR. PICs typically use assembly language, that is harder and limits the number of people who can contribute changes to the code. But you can start with a PC, maybe running Linux or BSD. 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. ___ 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] FE5680a arrived in boston $38 shipping included
Can you post or send me a pic of the Teddy Bear? -John == Well mine arrived Monday so about 3 weeks. Its the one without the useless to me oscillator. But I found it quite funny. It came bubble wrapped, cheap shipper mail as expected and commented in the list. But I have something far more valuable now then the oscillator. A teddy bear and 7805 regulator for the magical 5 V. There you go that 7508 was really protected by the teddy bear. Or They are dumping access teddy bears on the world market. ;-) Will fire up the unit tonight and see if I have the 2 sec pulse etc. Regards Paul WB8TSL ___ 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] Storage locker cleanout
Hi Bill, I may be interested in the Z3801s. Are you selling them locally only, or can you ship them? I'm in California. How much would you want for them? Ed Breya ___ 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-5680A Mechanical Question
Hi One way of looking at that: Back in 2003 or 2004 it left the factory exactly on frequency with a zero setting. (I'm betting there's a factory calibration register in there ..). You fire it up in seven years later and it's moved 5x10^-11. More or less it's drifted 1x10^-11 per year. Comes out to about 6x10^-13 per month. That's all based on a *lot* of wild guesses. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Thursday, January 12, 2012 6:58 PM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question Nigel I did not program it, it had its original setting and it is 9.944 which is -5.6 E-11, within 10 MHz which is within spec. Once I have some aging I will look at Voltage sensetivity. Bert Kehren In a message dated 1/12/2012 6:22:02 P.M. Eastern Standard Time, gandal...@aol.com writes: Hi Bert Could you clarify something for me please, before you started your tests did you program the unit to be close to 10MHz or did you leave it as received, and if so what is the actual frequency and is it stable? regards Nigel GM8PZR In a message dated 12/01/2012 21:50:28 GMT Standard Time, ewkeh...@aol.com writes: I hear all these ideas from paper tigers. How about building something and report on it. I can do a Shera for $ 40 and add a $ 20 GPS. And it works. I did fail to mention that I also have retrace data. Over the test period I had at least 10 power outages from seconds to a couple of hours. The Rb goes right back to 1 E-12. It would be nice if some one independent does a test on aging, maybe I was lucky and got a particularly good unit. ___ 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] FE-5680A Mechanical Question
Hi Rb's are sensitive to humidity, pressure, temperature, and magnetic field. You can probably control the temperature. With some effort you can control the humidity. Magnetic field and pressure are a bit harder. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray Sent: Thursday, January 12, 2012 8:49 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question jlt...@att.net said: While the project might be fun, for portable work, it is likely far easier and probably just as good (almost), to use a Tbolt. Somebody might have numbers for that, or be able to collect them. A TBolt that gets moved to a new location will have to do a new survey. How long does that take? How stable is the frequency during that time. How much better is it if the TBolt stays powered during the ride? How does that compare to a Rb? What's the recovery from power off look like for a Rb? How sensitive to vibration from transportation are they? -- 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. ___ 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-5680A arrived
Hi If you believe that your GPS is good to 1x10^-11 *and* that's good enough for what you are doing - the answer is easy. If you need 10X better than that, indeed it gets harder, but still in range for a TBolt. If you need 100X better, then it's very difficult. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray Sent: Thursday, January 12, 2012 8:48 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A arrived li...@rtty.us said: You would have to have either a *very* long loop (weeks?) and/or a *very* good GPS (big bucks) to keep from messing your Rb up. The alternative would be to simply do a comparison every two months and adjust it manually by the one or at most two DDS steps required. Yes, but how long do I measure when the two month timer goes off. Suppose I measure for a day. How do I know if I got a good day or was unlucky? Might as well collect everything and then analyze the whole pile. -- 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. ___ 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-5680A Mechanical Question
Hi Bert's Rb is performing better than it has any right to perform. He got lucky. At least that's my claim until I get a few measured here. Could be wrong... Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. L. Trantham Sent: Thursday, January 12, 2012 8:54 PM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] FE-5680A Mechanical Question Bob, You (and others) make a good point. The stability of a good Rb may be such that, in a portable operation, if you are going to be there for less than 2 weeks, why bother with the GPSDRbO option. Turn it on, adjust it to your GPSDO at home, turn it off, take it to the site, turn it on, use it, turn it off, bring it back home, turn it on and compare it to your GPSDO. I guess we'll have to wait for the 'aging' measurements from Bert and others to know the answer to this. Bert's initial measurement from his sounds like it is unlikely that we'll be able to improve very much from that, assuming all units perform similarly. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: Thursday, January 12, 2012 11:40 AM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] FE-5680A Mechanical Question Hi With the Rb pulling about 700 ma at 15 volts, it's going to nuke a battery pretty fast. You may find that (unlike an OCXO) the Rb comes back up to frequency fairly quickly (minutes /hours not days / weeks). Simply unplugging it and carrying it power off could be workable approach. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. L. Trantham Sent: Wednesday, January 11, 2012 11:56 PM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] FE-5680A Mechanical Question Bill, Brian, Bill, and Peter, Thanks for the info. All I need now is a 'project' to incorporate the unit into. In the back of my mind, I have the thought of a 'box' that will be battery powered or 110 VAC powered (perhaps with an internal SLA battery) and include a GPSDO and Rb unit (possibly a GPSDRbO) for the purpose of a 'reference' for portable operation in the microwave regions. Ah Dreaming! Makes looking forward to retiring very attractive! Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Peter Bell Sent: Wednesday, January 11, 2012 10:28 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question The pot accessible through the hole in the casing appears is the fine frequency adjust pot on the older units - on these, it's connected to an ADC input, but as far as I can see adjusting it does nothing at all. There are two screws hidden under the labels that hold the top over on - you also need to remove the two small screws on the side that bolt the D-type mounting bracket in place. Regards, Pete Bell On Thu, Jan 12, 2012 at 10:33 AM, J. L. Trantham jlt...@att.net wrote: Boy!!! I would have 'screwed' that up! Bill was correct. Mine were 1/16th inch Allen screws, not Torx as Brian has, and were very easily removed. They appear to be 3mm dia. X 5mm long with a 0.5mm pitch screw, in spite of having a 1/16th inch hex opening. There were two Phillips head screws underneath that appear to hold the bottom cover in place. On another topic, there is a small opening on the side (near the 'FE'Trademark) with what appears to be a multi-turn pot inside. What is that? Also, the 'sticker' on the top, that includes the 'FE' Trademark, 'FE-5680A', etc., has a 'soft spot' on the bottom edge. In addition, there is a 'soft spot' under the 'sticker' at the bottom of the front, near the connector, and includes the serial number. Does anyone know what is under these 'stickers'? Thanks again. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Brian, WA1ZMS Sent: Wednesday, January 11, 2012 8:52 PM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] FE-5680A Mechanical Question My rivets were tiny Torx screws. -Brian, WA1ZMS -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of J. L. Trantham Sent: Wednesday, January 11, 2012 9:22 PM To: 'Discussion of precise time and frequency measurement' Subject: [time-nuts] FE-5680A Mechanical Question Should I ever have time to pursue the Rb unit, what happens when I 'drill out' all the rivets that mount the unit to the PCB that it arrived on? Any reason to keep it on the PCB? Does the bottom cover come off? Will I need to replace the rivets with something else to keep the bottom cover on? Thanks in advance. Joe
Re: [time-nuts] FE-5680A Mechanical Question
Hi Common wisdom is that Rb's come back up pretty close to where they shut down. Weather it takes 10 minutes or two hours to get close on the specific Rb you have is indeed an open question. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Smither Sent: Thursday, January 12, 2012 9:55 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question J. L. Trantham wrote: Bob, You (and others) make a good point. The stability of a good Rb may be such that, in a portable operation, if you are going to be there for less than 2 weeks, why bother with the GPSDRbO option. Turn it on, adjust it to your GPSDO at home, turn it off, take it to the site, turn it on, use it, turn it off, bring it back home, turn it on and compare it to your GPSDO. This might work if all you are concerned with is the 10MHz. If the 1PPS from the Rb is to be used, it will come up at some random phase after the unit is powered off and back on. I have not done the power off - restart test to see how close the 10MHz recovers. Not sure I have anything that could measure it. Maybe it is time to order a 2nd Rb :-). ___ 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-5680A Mechanical Question
Hi I think it's pretty safe to guess that none of these units got reset in the field. What ever the end application, it just let them free run. Based on the number or pps missing units, I'd also bet it used the dirty 10 MHz output rather than the pps. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Chuck Forsberg WA7KGX N2469R Sent: Friday, January 13, 2012 12:05 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question Both of my units came with a stored preset of 0. Giving the second unit an offset of 0 results in an 84 second period for a 360 degree phase procession relative to a Thunderbolt's 10 MHz output. Call it 100 instead of 84 and we get 1e-9. Measure the distance to the Moon within a foot or two. On 01/12/2012 03:57 PM, ewkeh...@aol.com wrote: Nigel I did not program it, it had its original setting and it is 9.944 which is -5.6 E-11, within 10 MHz which is within spec. Once I have some aging I will look at Voltage sensetivity. Bert Kehren In a message dated 1/12/2012 6:22:02 P.M. Eastern Standard Time, gandal...@aol.com writes: Hi Bert Could you clarify something for me please, before you started your tests did you program the unit to be close to 10MHz or did you leave it as received, and if so what is the actual frequency and is it stable? regards Nigel GM8PZR In a message dated 12/01/2012 21:50:28 GMT Standard Time, ewkeh...@aol.com writes: I hear all these ideas from paper tigers. How about building something and report on it. I can do a Shera for $ 40 and add a $ 20 GPS. And it works. I did fail to mention that I also have retrace data. Over the test period I had at least 10 power outages from seconds to a couple of hours. The Rb goes right back to 1 E-12. It would be nice if some one independent does a test on aging, maybe I was lucky and got a particularly good unit. ___ 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. -- Chuck Forsberg WA7KGX N2469R c...@omen.com www.omen.com Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc The High Reliability Software 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 ___ 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-5680A PPS on pin 6 (or not)
Hi I'd suggest lurking on the usual sites for a cheap TBolt. It will give you a *much* better pps to compare to and you can do some amazing things with Lady Heather. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Miller Sent: Friday, January 13, 2012 1:19 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A PPS on pin 6 (or not) Hello Group, I have been lurking for a while to get a feel for the group and hope to give back something in return for all the good information found so far. I have two of the FE-5680A units from the usual source. They both worked and were much less than 1 Hz off compared to a Trak Microwave GPSDRb house clock. Can't say this is not one of the treasures found in modern surplus sources. I made one observation about the 1 PPS signal. It is not present until the unit achieves lock. The 10 MHz signal is there at power up. I would be interested in using a vanilla GPS receiver that has the 1 PPS signal to sync up the Rb clock so I am following those threads. Thanks much, Tom -- Message: 2 Date: Thu, 12 Jan 2012 03:23:00 +0100 From: EB4APL eb4...@cembreros.jazztel.es To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A PPS on pin 6 (or not) Message-ID: 4f0e4404.8070...@cembreros.jazztel.es Content-Type: text/plain; charset=ISO-8859-1; format=flowed Hi, I'm interested in seen those photos, because I collected a bunch of then from various owners but I dont see this 'AC161 even on in the switching regulator pair. I made a goof the other day when I connected the 5 V input to a 15 V power supply and toasted the 'ACT240 buffer which drives the lock indicator and the PPS outputs. I know that the 5 V is used to generate the +3.3 V in an internal regulator and because I'm not sure what else is toasted I want to trace this voltage and see if it is ok. The unit is mostly working, it locks and also generates the 1PPS, measured at the input pin of the buffer, but I want to check everything that can be damaged and replace the failed parts. So I'll benefit from partial schematics, parts location and identifications and all the like. Please share the info that you have. Best regards, Ignacio, EB4APL ___ 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] Lady Heather S/W
Hi Lady Heather does not seem to like the Trimble CDMA units. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of VK3YV Sent: Friday, January 13, 2012 1:47 AM To: time-nuts@febo.com Subject: [time-nuts] Lady Heather S/W Hi all, can anyone tell me whether Lady Heather S/W is compatible with the ex Trimble CDMA 10 Mhz reference units that run with the Thunderbolt S/W ok. Many thanks, Don ...VK3YV ___ 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] FE5680a arrived in boston $38 shipping included
You can have mine. Peter On Jan 13, 2012, at 12:08 PM, J. Forster j...@quikus.com wrote: Can you post or send me a pic of the Teddy Bear? -John == Well mine arrived Monday so about 3 weeks. Its the one without the useless to me oscillator. But I found it quite funny. It came bubble wrapped, cheap shipper mail as expected and commented in the list. But I have something far more valuable now then the oscillator. A teddy bear and 7805 regulator for the magical 5 V. There you go that 7508 was really protected by the teddy bear. Or They are dumping access teddy bears on the world market. ;-) Will fire up the unit tonight and see if I have the 2 sec pulse etc. Regards Paul WB8TSL ___ 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] FE-5680A tear down on Youtube
Hi Interesting videos. Answers to a couple of the questions he asks in the tear down video: The foam is there as thermal insulation. It's not for mechanical support. The gizmo on top of the crystal is a rapid transition thermistor. The Russians came up with them for use in OCXO's back in the 1970's. It's there to heat the VCXO crystal, sort of an OCXO. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of lists Sent: Friday, January 13, 2012 4:09 AM To: time-nuts@febo.com Subject: [time-nuts] FE-5680A tear down on Youtube Hi, This is my first post to the list, but I have been a long time reader and found it extremely interesting and informative. I think you guys might find this interesting.. Its a video of a FE-5680A being dissembled on Youtube. I had noticed that within hours of the video being published 14 of the cheaper 5680A's were sold! as the producer of the video (not me) has over 14,800 subscribers, my thoughts are that this may have some effect on the used FE-5680A price or even advanced depletion of the stock.. I'm glad mines on the boat already. The tear down: http://www.youtube.com/watch?v=FRdGsSu5Nec The theory of operation: http://www.youtube.com/watch?v=I55uLRRvLCU Sam. ___ 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-5680A Mechanical Question
Hi Another thing that would need to be investigated - How fast (and how uniformly) does it respond to a frequency set command. If you dither, you care about how long it's at this or that frequency. Measuring 7x10^-13 frequency shifts on the unit probably isn't the best way to check that out Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Friday, January 13, 2012 6:20 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren In a message dated 1/12/2012 12:20:15 P.M. Eastern Standard Time, li...@rtty.us writes: Hi I think it would be worth the effort to try dithering the DDS commands into the Rb while measuring ADEV. You *might* find that you can do it with little or no impact on the unit's stability. If so it takes out some modification effort and should make the controller cheaper. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Thursday, January 12, 2012 10:43 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question Bringing out the C field in my estimation does not effect long or short term. External magnetic field I think is a joke. An other option is a loop that generates a tuning word for the DDS but that means your steps are 7 E-13. Bert Kehren In a message dated 1/12/2012 10:34:10 A.M. Eastern Standard Time, davidwh...@gmail.com writes: I was more interested in the technical details of how to adjust the output of a RbO without sacrificing the short and long term stability. I have seen a few designs that used a DDS to generate the 10 MHz output which lends itself to this but they all suffer from DDS and tuning noise. I see now that the RbO can be adjusted with an external magnetic field. On Thu, 12 Jan 2012 07:34:44 -0600, J. L. Trantham jlt...@att.net wrote: David, I have been following discussions on the list about a GPSDRbO for a year or so. Some interesting challenges and probably best implemented in a 'stable' environment rather than portable operation but as best I can tell, it would require a very stable and good antenna location, stable and clean power, and I was thinking of using something like an LPRO-101 with an Ext C Field input, a Shera type controller, and a GPS timing receiver, though, I suspect there are likely to be some 'multi-tasking' receivers out there that will look at several sources including GPS, GLOSNASS, etc. While the project might be fun, for portable work, it is likely far easier and probably just as good (almost), to use a Tbolt. In any event, something to think about for the future. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of David Sent: Wednesday, January 11, 2012 11:12 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question How would a GPSDRbO work? Phase lock the DDS output to the GPS? Phase lock a VCXO to the GPS and then phase lock to the RbO on loss of GPS lock? On Wed, 11 Jan 2012 22:55:58 -0600, J. L. Trantham jlt...@att.net wrote: Bill, Brian, Bill, and Peter, Thanks for the info. All I need now is a 'project' to incorporate the unit into. In the back of my mind, I have the thought of a 'box' that will be battery powered or 110 VAC powered (perhaps with an internal SLA battery) and include a GPSDO and Rb unit (possibly a GPSDRbO) for the purpose of a 'reference' for portable operation in the microwave regions. ___ 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
Re: [time-nuts] FE-5680A Mechanical Question
we would be talking +- one step and using different rate but reading the frequency over 1000 seconds would be my answer. Start at 1 1 Hz rate and observe the lock indicator. At the same time measure frequency. Bert Kehren In a message dated 1/13/2012 12:52:16 P.M. Eastern Standard Time, li...@rtty.us writes: Hi Another thing that would need to be investigated - How fast (and how uniformly) does it respond to a frequency set command. If you dither, you care about how long it's at this or that frequency. Measuring 7x10^-13 frequency shifts on the unit probably isn't the best way to check that out Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Friday, January 13, 2012 6:20 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren In a message dated 1/12/2012 12:20:15 P.M. Eastern Standard Time, li...@rtty.us writes: Hi I think it would be worth the effort to try dithering the DDS commands into the Rb while measuring ADEV. You *might* find that you can do it with little or no impact on the unit's stability. If so it takes out some modification effort and should make the controller cheaper. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Thursday, January 12, 2012 10:43 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question Bringing out the C field in my estimation does not effect long or short term. External magnetic field I think is a joke. An other option is a loop that generates a tuning word for the DDS but that means your steps are 7 E-13. Bert Kehren In a message dated 1/12/2012 10:34:10 A.M. Eastern Standard Time, davidwh...@gmail.com writes: I was more interested in the technical details of how to adjust the output of a RbO without sacrificing the short and long term stability. I have seen a few designs that used a DDS to generate the 10 MHz output which lends itself to this but they all suffer from DDS and tuning noise. I see now that the RbO can be adjusted with an external magnetic field. On Thu, 12 Jan 2012 07:34:44 -0600, J. L. Tranthamjlt...@att.net wrote: David, I have been following discussions on the list about a GPSDRbO for a year or so. Some interesting challenges and probably best implemented in a 'stable' environment rather than portable operation but as best I can tell, it would require a very stable and good antenna location, stable and clean power, and I was thinking of using something like an LPRO-101 with an Ext C Field input, a Shera type controller, and a GPS timing receiver, though, I suspect there are likely to be some 'multi-tasking' receivers out there that will look at several sources including GPS, GLOSNASS, etc. While the project might be fun, for portable work, it is likely far easier and probably just as good (almost), to use a Tbolt. In any event, something to think about for the future. Joe -OriginalMessage- From: time-nuts-boun...@febo.com[mailto:time-nuts-boun...@febo.com] On Behalf Of David Sent: Wednesday, January 11, 2012 11:12 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question How would a GPSDRbO work? Phase lock the DDS output to the GPS? Phase lock a VCXO to the GPS and then phase lock to the RbO on loss of GPS lock? On Wed, 11 Jan 2012 22:55:58 -0600, J. L. Trantham jlt...@att.net wrote: Bill, Brian, Bill, and Peter, Thanks for the info. All I need now is a 'project' to incorporate the unit into. In the back of my mind, I have the thought of a 'box' that will be battery powered or 110 VAC powered (perhaps with an internal SLA battery) and include a GPSDO and Rb unit (possibly a GPSDRbO) for the purpose of a 'reference' for portable operation in themicrowave regions. ___ time-nutsmailing list -- time-nuts@febo.com To unsubscribe, goto
Re: [time-nuts] FE-5680A Mechanical Question
If dither is a consideration it will be the most critical test. Bert Kehren In a message dated 1/13/2012 12:52:16 P.M. Eastern Standard Time, li...@rtty.us writes: Hi Another thing that would need to be investigated - How fast (and how uniformly) does it respond to a frequency set command. If you dither, you care about how long it's at this or that frequency. Measuring 7x10^-13 frequency shifts on the unit probably isn't the best way to check that out Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Friday, January 13, 2012 6:20 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren In a message dated 1/12/2012 12:20:15 P.M. Eastern Standard Time, li...@rtty.us writes: Hi I think it would be worth the effort to try dithering the DDS commands into the Rb while measuring ADEV. You *might* find that you can do it with little or no impact on the unit's stability. If so it takes out some modification effort and should make the controller cheaper. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ewkeh...@aol.com Sent: Thursday, January 12, 2012 10:43 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question Bringing out the C field in my estimation does not effect long or short term. External magnetic field I think is a joke. An other option is a loop that generates a tuning word for the DDS but that means your steps are 7 E-13. Bert Kehren In a message dated 1/12/2012 10:34:10 A.M. Eastern Standard Time, davidwh...@gmail.com writes: I was more interested in the technical details of how to adjust the output of a RbO without sacrificing the short and long term stability. I have seen a few designs that used a DDS to generate the 10 MHz output which lends itself to this but they all suffer from DDS and tuning noise. I see now that the RbO can be adjusted with an external magnetic field. On Thu, 12 Jan 2012 07:34:44 -0600, J. L. Tranthamjlt...@att.net wrote: David, I have been following discussions on the list about a GPSDRbO for a year or so. Some interesting challenges and probably best implemented in a 'stable' environment rather than portable operation but as best I can tell, it would require a very stable and good antenna location, stable and clean power, and I was thinking of using something like an LPRO-101 with an Ext C Field input, a Shera type controller, and a GPS timing receiver, though, I suspect there are likely to be some 'multi-tasking' receivers out there that will look at several sources including GPS, GLOSNASS, etc. While the project might be fun, for portable work, it is likely far easier and probably just as good (almost), to use a Tbolt. In any event, something to think about for the future. Joe -OriginalMessage- From: time-nuts-boun...@febo.com[mailto:time-nuts-boun...@febo.com] On Behalf Of David Sent: Wednesday, January 11, 2012 11:12 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FE-5680A Mechanical Question How would a GPSDRbO work? Phase lock the DDS output to the GPS? Phase lock a VCXO to the GPS and then phase lock to the RbO on loss of GPS lock? On Wed, 11 Jan 2012 22:55:58 -0600, J. L. Trantham jlt...@att.net wrote: Bill, Brian, Bill, and Peter, Thanks for the info. All I need now is a 'project' to incorporate the unit into. In the back of my mind, I have the thought of a 'box' that will be battery powered or 110 VAC powered (perhaps with an internal SLA battery) and include a GPSDO and Rb unit (possibly a GPSDRbO) for the purpose of a 'reference' for portable operation in themicrowave regions. ___ time-nutsmailing list -- time-nuts@febo.com To unsubscribe, goto https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts andfollow the instructionsthere. ___ time-nuts
[time-nuts] GPS testing
GPS Testing January 16, 2012 aEUR January 24, 2012 Patuxent River, MD. Notice Number: NOTC3454 GPS Testing PAXR GPS 12-01 January 16, 2012 aEUR January 24, 2012 Patuxent River, MD. See attached document for more details. https://www.faasafety.gov/files/notices/2012/Jan/PAX12-01_GPS_Flight_Ad visory.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] Storage locker cleanout
Oops. That last message was supposed to be off-list. Sorry. Ed ___ 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-5680A Mechanical Question
On Fri, Jan 13, 2012 at 8:37 AM, Jim Lux jim...@earthlink.net wrote: On 1/13/12 8:15 AM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 3:19 AM,ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one. Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage. Many already have audio input with 24-bit ADC chips. But those audio inputs are almost always AC coupled. Bringing up a question: Does anyone know of a cheap ($20ish) USB voltage sensor (16 bits or better, ideally).. I can see one of those Atmel USB capable micros (like the one on the Arduino Uno) hooked to a dual slope or successive approximation ADC. There seem to be an amazing number of times that I want something like that. The DATAQ $29 widget is only 10 bits, unfortunately. A USB interface DMM would work nicely, but I haven't found one that's in the under $50 price Many computer audio interfaces are AC coupled but not all of them. But even with AC coupling what you can do is use the VCO portion of a CD4046. This will convert voltage to frequency in the audio range. It's a cheap work around. But really not because frequency in nearly imune to noise and can be sent over long cables. What I really want is a lower price GBIP interface. I just bought an HP5328A on eBay that has the option 21 DVM. This meter can measure volts to about 5 digits and send the data out the GPIB but getting that into a computer is the hard part. OK so I check on eBay. Most are $300 but If you can find a computer with an old ISA slot then there are working GBIB cards for about $20. The trick is finding an old PC. These are AT class or early Pentium type computers. Most of these are now in landfills some place. But now I will be looking. I do software all day, every day. From experience, I can say it is MUCH more productive to develop code on a larger desktop computer. Better tools are available. Then move it down to the target computer after you have it debugged. The process is helped if the target computer is like the desktop computer. There is a lot we don't know about the FE5680, like how fast can you move the phase of the PPS? Does the FE5680 maintain lock when you step the DDS? how fast can you step the DDS. All this will take experiments. best to do those on the big desktop machine where we have tools to log data to disk, make plots and so on. Again, if anyone makes PCBs PLEASE include a way to program the uP on the card without need of extra hardware. The firmware will get upgraded and not everyone has a programmer. There must be a way for end users upgrade the firmware. -- 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] FE-5680A Mechanical Question
I think the dither issue should be explored separately. Its finding should be included in the Controller. During development I understand the need for on the board programming, but unlike OCXO's which there are many of, I envision this controller dedicated to the FEI 5680A using 10 MHz and a 1 pps input. With no flexability the total cost can be kept below $ 15. If cost is not an issue many things can be done. Bert Kehren In a message dated 1/13/2012 1:34:51 P.M. Eastern Standard Time, albertson.ch...@gmail.com writes: On Fri, Jan 13, 2012 at 8:37 AM, Jim Lux jim...@earthlink.net wrote: On 1/13/12 8:15 AM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 3:19 AM,ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one. Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage. Many already have audio input with 24-bit ADC chips. But those audio inputs are almost always AC coupled. Bringing up a question: Does anyone know of a cheap ($20ish) USB voltage sensor (16 bits or better, ideally).. I can see one of those Atmel USB capable micros (like the one on the Arduino Uno) hooked to a dual slope or successive approximation ADC. There seem to be an amazing number of times that I want something like that. The DATAQ $29 widget is only 10 bits, unfortunately. A USB interface DMM would work nicely, but I haven't found one that's in the under $50 price Many computer audio interfaces are AC coupled but not all of them. But even with AC coupling what you can do is use the VCO portion of a CD4046. This will convert voltage to frequency in the audio range. It's a cheap work around. But really not because frequency in nearly imune to noise and can be sent over long cables. What I really want is a lower price GBIP interface.I just bought an HP5328A on eBay that has the option 21 DVM. This meter can measure volts to about 5 digits and send the data out the GPIB but getting that into a computer is the hard part. OK so I check on eBay. Most are $300 but If you can find a computer with an old ISA slot then there are working GBIB cards for about $20. The trick is finding an old PC. These are AT class or early Pentium type computers. Most of these are now in landfills some place. But now I will be looking. I do software all day, every day. From experience, I can say it is MUCH more productive to develop code on a larger desktop computer. Better tools are available. Then move it down to the target computer after you have it debugged. The process is helped if the target computer is like the desktop computer. There is a lot we don't know about the FE5680, like how fast can you move the phase of the PPS? Does the FE5680 maintain lock when you step the DDS? how fast can you step the DDS.All this will take experiments. best to do those on the big desktop machine where we have tools to log data to disk, make plots and so on. Again, if anyone makes PCBs PLEASE include a way to program the uP on the card without need of extra hardware. The firmware will get upgraded and not everyone has a programmer. There must be a way for end users upgrade the firmware. -- 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. ___ 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-5680A tear down on Youtube
same conclusion I made that it was a heater and insulation. But at least it was a good video Regards Paul On Fri, Jan 13, 2012 at 12:50 PM, Bob Camp li...@rtty.us wrote: Hi Interesting videos. Answers to a couple of the questions he asks in the tear down video: The foam is there as thermal insulation. It's not for mechanical support. The gizmo on top of the crystal is a rapid transition thermistor. The Russians came up with them for use in OCXO's back in the 1970's. It's there to heat the VCXO crystal, sort of an OCXO. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of lists Sent: Friday, January 13, 2012 4:09 AM To: time-nuts@febo.com Subject: [time-nuts] FE-5680A tear down on Youtube Hi, This is my first post to the list, but I have been a long time reader and found it extremely interesting and informative. I think you guys might find this interesting.. Its a video of a FE-5680A being dissembled on Youtube. I had noticed that within hours of the video being published 14 of the cheaper 5680A's were sold! as the producer of the video (not me) has over 14,800 subscribers, my thoughts are that this may have some effect on the used FE-5680A price or even advanced depletion of the stock.. I'm glad mines on the boat already. The tear down: http://www.youtube.com/watch?v=FRdGsSu5Nec The theory of operation: http://www.youtube.com/watch?v=I55uLRRvLCU Sam. ___ 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] 5680 RS232
Can some one tell me which RS232 chip is used in the 5680. Thank you. ___ 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] cheap USB voltage sensor
Bringing up a question: Does anyone know of a cheap ($20ish) USB voltage sensor (16 bits or better, ideally).. I can see one of those Atmel USB capable micros (like the one on the Arduino Uno) hooked to a dual slope or successive approximation ADC. Doesn't quite meet your price, but there's a 3.3V version of an Arduino called a JeeNode designed for sensor work, and there are a number of I2C based sensor plugins for it. For example the analog plug based on Microchip MCP3424 with 4 channels of differential inputs at 18 bits. Jeenode (kit) is $23 and Analog plug (assembled) is $12. It's the standard Arduino architecture, so it is simple to use and (re-)program from your PC via USB, no extra programmer needed. http://shop.moderndevice.com/products/jeenode-kit http://shop.moderndevice.com/products/jeelabs-analog-plug I have some and they work well. Here's a plot of voltage vs time on an AA battery, showing the 18 bit performance (1 LSB = 15 uV). Noise is generally +/-1 LSB. https://picasaweb.google.com/lh/photo/q7Lq4oAX_0347S8BO0eHSA You can plug up to four analog plugs directly into the JeeNode (software I2C) and these can actually be daisy-chained as well, with 6 different I2C addresses per I2C chain, for up to 24 total plugs per JeeNode which would be 96 ADC channels. If you are in Europe you can buy hardware direct from the designer at http://jeelabs.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] cheap USB voltage sensor
In message 20120113200200.14805.qm...@s421.sureserver.com, =?iso-8859-1?Q?be ale?= writes: I have some and they work well. Here's a plot of voltage vs time on an AA battery, showing the 18 bit performance (1 LSB = 15 uV). Noise is generally +/-1 LSB. https://picasaweb.google.com/lh/photo/q7Lq4oAX_0347S8BO0eHSA Did you try to hold the battery in your hand while you did that ? :-) Be aware that once you get to approx microvolt, you have to take into account things like the temperature difference between plug and socket because the thermoelectric effect kicks in. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] cheap USB voltage sensor
If you have a PC and an AC coupled audio interface then send a low frequency audio saw tooth wave to the audio out. Connect that and the device to be measured to an LM311 comparator. The comparator will flip when your output voltage passes the DUT's voltage. One could get fancy and use multiple comparators Then connect the comparator(s) to a parallel port. You get 8 channels of low bandwidth analog input for about 25 cents per channel, if you already have the parallel port. I think that is the cheapest possible way to get voltages into a computer. Also this kind of ADC can be very accurate. You can tie one or more of the LM311s to a voltage reference and then your instrument is continuoly calibrated. This works because in our case the signal, has low bandwidth so we can take out time and collect 1000 samples On Fri, Jan 13, 2012 at 12:02 PM, beale be...@bealecorner.com wrote: Bringing up a question: Does anyone know of a cheap ($20ish) USB voltage sensor (16 bits or better, ideally).. I can see one of those Atmel USB capable micros (like the one on the Arduino Uno) hooked to a dual slope or successive approximation ADC. Doesn't quite meet your price, but there's a 3.3V version of an Arduino called a JeeNode designed for sensor work, and there are a number of I2C based sensor plugins for it. For example the analog plug based on Microchip MCP3424 with 4 channels of differential inputs at 18 bits. Jeenode (kit) is $23 and Analog plug (assembled) is $12. It's the standard Arduino architecture, so it is simple to use and (re-)program from your PC via USB, no extra programmer needed. http://shop.moderndevice.com/products/jeenode-kit http://shop.moderndevice.com/products/jeelabs-analog-plug I have some and they work well. Here's a plot of voltage vs time on an AA battery, showing the 18 bit performance (1 LSB = 15 uV). Noise is generally +/-1 LSB. https://picasaweb.google.com/lh/photo/q7Lq4oAX_0347S8BO0eHSA You can plug up to four analog plugs directly into the JeeNode (software I2C) and these can actually be daisy-chained as well, with 6 different I2C addresses per I2C chain, for up to 24 total plugs per JeeNode which would be 96 ADC channels. If you are in Europe you can buy hardware direct from the designer at http://jeelabs.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. -- 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] FE-5680A Mechanical Question
wrong there is no DAC involved, it is a DDS In a message dated 1/13/2012 3:36:33 P.M. Eastern Standard Time, charles_steinm...@lavabit.com writes: Bert wrote: we would be talking +- one step and using different rate but reading the frequency over 1000 seconds would be my answer. Rather than dithering the existing 7e-13 steps, perhaps it would be simpler to adjust the 5680A step size? Presumably, the C-field is being controlled by the current or voltage output of a DAC, and the 7e-13 steps represent the LSB of the DAC. From the reports so far on the list, the DAC output range is much larger than necessary (I think someone said ~ +/- 2 Hz ??). If you attenuate the DAC output by 10x in the analog domain, you would have a +/- 0.2 Hz range with 7e-14 steps (or, if you like, attenuate by 7 for 1e-13 steps, or by 14 for 5e-14 steps). You would have to be a little careful about the tempco of the implementation (particularly, you may need to add some low-tempco bias to get the range centered on 10.0 MHz again), but I wouldn't think it would be so critical as to be beyond the ability of the home time nut. Best regards, Charles ___ 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-5680A Mechanical Question
Bert wrote: wrong there is no DAC involved, it is a DDS Ahh. Not so simple, then. I still don't much like the notion of dithering, but it may be the only alternative. Or, as has also been suggested here, add a manual C-field adjustment (but that would not change the fact that the RS-232 adjustments would still be ~ 7e-13 steps). Best regards, Charles ___ 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 interference and history...
On Fri, Jan 13, 2012 at 6:29 AM, Jim Lux jim...@earthlink.net wrote: I suppose one could use some sort of GPRS cellular service and get time, but then you're on the hook for a monthly subscription fee, etc. They sell such devices. They don't require a subscription because they are receive-only. You don't need to send data to get time.I don't know about GPRS, but there have been commercial CDMA time receivers on the market for years. People who don't have access to the sky but do get cell phone service buy them. For example you are on the 14th floor of a 50 floor office building and your window faces another building. That is the biggest problem with GPS, you need access to the sky. cheap L1 only GPS is a great solution. Apply power, wait, you've got accurate time. No need to have someone visit periodically and check to see if the clock needs to be reset, etc. I'm not sure why they need GPS at the recording house. They know where it is so timing is the only use I can think of. But they could also get that at the receiving end. Millisecond accuracy isn't helpful. Second level accuracy might be interesting if something breaks and you want to know when the wave got to downstream stations. The risetime is probably over a second. You're right, they don't need milliseconds, nor do they need seconds, probably. There's really no other convenient way to get time to the nearest minute that is as reliable and cheap as GPS. Think about it... WWVB? WWV? Vertical pointing sun sensor? ___ 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] FE-5680A Mechanical Question
I would just use a picaxe, has a simple to use IDE and several different sizes. No need for assembly, cheap enough for quasi-production. Don Chris Albertson On Fri, Jan 13, 2012 at 3:19 AM, ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one. Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage. Many already have audio input with 24-bit ADC chips. Later you can move the C code from the PC pretty much directly to an AVR. PICs typically use assembly language, that is harder and limits the number of people who can contribute changes to the code. But you can start with a PC, maybe running Linux or BSD. 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] 5680 RS232
Mine reads: MAX3232EWE 0332 and has a 16 SOIC(W);16 pin package. John WA4WDL -- From: ewkeh...@aol.com Sent: Friday, January 13, 2012 2:17 PM To: time-nuts@febo.com Subject: [time-nuts] 5680 RS232 Can some one tell me which RS232 chip is used in the 5680. Thank you. ___ 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] 5680 RS232
Thank you. That takes care of it. In a message dated 1/13/2012 3:58:47 P.M. Eastern Standard Time, jmfra...@cox.net writes: Mine reads: MAX3232EWE 0332 and has a 16 SOIC(W);16 pin package. John WA4WDL -- From: ewkeh...@aol.com Sent: Friday, January 13, 2012 2:17 PM To: time-nuts@febo.com Subject: [time-nuts] 5680 RS232 Can some one tell me which RS232 chip is used in the 5680. Thank you. ___ 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] FE-5680A Mechanical Question
Dither is only an issue when using a control loop. The difference is that with dithering you eliminate the D/A portion which doubles the cost from $ 15 to $ 30. I personally prefer the analog approach. The same design can have both options. Part of the program. Bert Kehren In a message dated 1/13/2012 3:48:19 P.M. Eastern Standard Time, charles_steinm...@lavabit.com writes: Bert wrote: wrong there is no DAC involved, it is a DDS Ahh. Not so simple, then. I still don't much like the notion of dithering, but it may be the only alternative. Or, as has also been suggested here, add a manual C-field adjustment (but that would not change the fact that the RS-232 adjustments would still be ~ 7e-13 steps). Best regards, Charles ___ 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-5680A Mechanical Question
Can you do the programming? Bert Kehren In a message dated 1/13/2012 3:56:47 P.M. Eastern Standard Time, d...@montana.com writes: I would just use a picaxe, has a simple to use IDE and several different sizes. No need for assembly, cheap enough for quasi-production. Don Chris Albertson On Fri, Jan 13, 2012 at 3:19 AM, ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one.Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage.Many already have audio input with 24-bit ADC chips. Later you can move the C code from the PC pretty much directly to an AVR. PICs typically use assembly language, that is harder and limits the number of people who can contribute changes to the code. But you can start with a PC, maybe running Linux or BSD. 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] cheap USB voltage sensor
Right, Poul! And I've found, by lots of headbanging on walls, GROUNDLOOPS! even at 12 bits... Don Poul-Henning Kamp In message 20120113200200.14805.qm...@s421.sureserver.com, =?iso-8859-1?Q?be ale?= writes: I have some and they work well. Here's a plot of voltage vs time on an AA battery, showing the 18 bit performance (1 LSB = 15 uV). Noise is generally +/-1 LSB. https://picasaweb.google.com/lh/photo/q7Lq4oAX_0347S8BO0eHSA Did you try to hold the battery in your hand while you did that ? :-) Be aware that once you get to approx microvolt, you have to take into account things like the temperature difference between plug and socket because the thermoelectric effect kicks in. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] FE-5680A Mechanical Question
Oh, I hate to be a pedant, but are we talking about dithering, that is random perturbations to remove things like hysteresis, or using the finite steps as a bang-bang servo? Don Charles P. Steinmetz Bert wrote: wrong there is no DAC involved, it is a DDS Ahh. Not so simple, then. I still don't much like the notion of dithering, but it may be the only alternative. Or, as has also been suggested here, add a manual C-field adjustment (but that would not change the fact that the RS-232 adjustments would still be ~ 7e-13 steps). Best regards, Charles ___ 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] FE-5680A Mechanical Question
Hi Bert: The point to the picaxe is that you can do your own programming; the learning curve is very shallow, there is a really good manual, and the investment is really very small. There is a very large user community, too. Investigate at: http://www.picaxe.com/ The picaxe started out in England for high schoolers. Completely OT, it seems to me that most of the good small hobby-style stuff has come from Australia and England, rather than the US. Kinda tracks the death of the space program, and thousands of wimpy apps for some overpriced piece of hardware. . . Wait one minute for responses until I get the pot to cover my head :-) Don ewkeh...@aol.com Can you do the programming? Bert Kehren In a message dated 1/13/2012 3:56:47 P.M. Eastern Standard Time, d...@montana.com writes: I would just use a picaxe, has a simple to use IDE and several different sizes. No need for assembly, cheap enough for quasi-production. Don Chris Albertson On Fri, Jan 13, 2012 at 3:19 AM, ewkeh...@aol.com wrote: What we know is that you can set the Rb in 7 E-13. Dithering would allow even closer setting, the question is what rate will the Rb accept with out loosing lock or deterioration of the performance. Some one should explore that. I am still waiting to se some aging. Taking the 10 MHz output and than use an analog loop and something like a Morion OCXO and you have the best of all. Digitally controlling the Rb will cut the cost of the control loop in half. For $10 in parts and a PC board for less than $10 using Shera like controller can be realized. What is needed is some one able to do the PIC. If some one is interested and able, please contact me off list. A low cost GPS or a 1 pps output of a Tbolt be perfect source. Bert Kehren Don't use a PIC for the prototype. A desktop PC could work as well and everyone here already has one.Connect the FE5680 to the PC's serial port and send commands to adjust it. The PC also needs to be able to read a voltage.Many already have audio input with 24-bit ADC chips. Later you can move the C code from the PC pretty much directly to an AVR. PICs typically use assembly language, that is harder and limits the number of people who can contribute changes to the code. But you can start with a PC, maybe running Linux or BSD. 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] FE-5680A Mechanical Question
Hi What we are talking about is toggling the least significant bit in the DDS to achieve a resolution of less than that LSB. It could be done to a set period (like a PWM) or pseudo randomly to reduce the noise signature. Either way, roughly a 16 element long period should be quite adequate. 7x10^-16 / 16 would give us a 4x10^-14 step and a 2x10^-14 max error. Bob On Jan 13, 2012, at 4:30 PM, Don Latham wrote: Oh, I hate to be a pedant, but are we talking about dithering, that is random perturbations to remove things like hysteresis, or using the finite steps as a bang-bang servo? Don Charles P. Steinmetz Bert wrote: wrong there is no DAC involved, it is a DDS Ahh. Not so simple, then. I still don't much like the notion of dithering, but it may be the only alternative. Or, as has also been suggested here, add a manual C-field adjustment (but that would not change the fact that the RS-232 adjustments would still be ~ 7e-13 steps). Best regards, Charles ___ 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] FE-5680A Mechanical Question
Are we not overdoing it. 7E-13 for $15 KISS, and if you want to go beyond that use a $ 30 analog version. Looking right now at 1 E -14, I do se temperature influences, with my heat sink stable to .1 C. Mainly due to the fact that is only one side of the unit and it is clearly designed to use all sides for heat dissipation. Bert Kehren In a message dated 1/13/2012 5:02:48 P.M. Eastern Standard Time, li...@rtty.us writes: Hi What we are talking about is toggling the least significant bit in the DDS to achieve a resolution of less than that LSB. It could be done to a set period (like a PWM) or pseudo randomly to reduce the noise signature. Either way, roughly a 16 element long period should be quite adequate. 7x10^-16 / 16 would give us a 4x10^-14 step and a 2x10^-14 max error. Bob On Jan 13, 2012, at 4:30 PM, Don Latham wrote: Oh, I hate to be a pedant, but are we talking about dithering, that is random perturbations to remove things like hysteresis, or using the finite steps as a bang-bang servo? Don Charles P. Steinmetz Bert wrote: wrong there is no DAC involved, it is a DDS Ahh. Not so simple, then. I still don't much like the notion of dithering, but it may be the only alternative. Or, as has also been suggested here, add a manual C-field adjustment (but that would not change the fact that the RS-232 adjustments would still be ~ 7e-13 steps). Best regards, Charles ___ 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] FE-5680A Mechanical Question
albertson.ch...@gmail.com said: and send the data out the GPIB but getting that into a computer is the hard part. OK so I check on eBay. Most are $300 but If you can find a computer with an old ISA slot then there are working GBIB cards for about $20. Many of us are happy with the Prologix. The USB version is $150. That's more than I really want to spend but less than $300 and you don't have to maintain an old PC. The USB version uses one of the popular USB-RS232 chips so there is no problem with drivers. I haven't tried the Ethernet version. http://prologix.biz/ http://www.sparkfun.com/search/results?term=GPIBwhat=products -- 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] FE-5680A Mechanical Question
On Fri, Jan 13, 2012 at 1:09 PM, ewkeh...@aol.com wrote: Can you do the programming? Bert Kehren (1) ANYONE can program a picaxe, that is their main selling point. (2) The next question is Can you describe in detail, using plain English exactly what needs to be programmed? If so then go to (1). Seriously, if you can write English in the style of the above (numbered sentences, clear decision points,...) you can transliterate it into the Basic that picaxes use. -- 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] FE-5680A Mechanical Question
On 1/13/2012 4:30 PM, Don Latham wrote: Oh, I hate to be a pedant, but are we talking about dithering, that is random perturbations to remove things like hysteresis, or using the finite steps as a bang-bang servo? Not random, but a PWM like control to get better precision from a given granularity. If a device only has whole number steps (1,2,3...), and you want something in between, then you dither it. If you want 1.6, have it spend 40% of its time at 1, and 60% at 2. Nothing random about it. What's bang-bang servo? (other than a techno band - http://www.myspace.com/bangbangservo ) ___ 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-5680A Mechanical Question
On Fri, Jan 13, 2012 at 2:19 PM, ewkeh...@aol.com wrote: Are we not overdoing it. 7E-13 for $15 KISS, and if you want to go beyond that use a $ 30 analog version. Looking right now at 1 E -14, I do se temperature influences, with my heat sink stable to .1 C. Mainly due to the fact that is only one side of the unit and it is clearly designed to use all sides for heat dissipation. Technical question, how does one measure 1E-14 changes in frequency? I'm thinking about building a controller and of course you can't control what you can't measure. But at that small level what do you use for a reference? 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] FE-5680A Mechanical Question
What's bang-bang servo? (other than a techno band - http://www.myspace.com/bangbangservo ) A home thermostat is the best example. It is a servo with no proportional control, just on and off. 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] FE-5680A Mechanical Question
On 1/13/12 2:33 PM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 2:19 PM,ewkeh...@aol.com wrote: Are we not overdoing it. 7E-13 for $15 KISS, and if you want to go beyond that use a $ 30 analog version. Looking right now at 1 E -14, I do se temperature influences, with my heat sink stable to .1 C. Mainly due to the fact that is only one side of the unit and it is clearly designed to use all sides for heat dissipation. Technical question, how does one measure 1E-14 changes in frequency? I'm thinking about building a controller and of course you can't control what you can't measure. But at that small level what do you use for a reference? Your other sources. Seriously.. Of course, the man who has two clocks doesn't know what time it is. If you have 3 sources, you can do three cornered hat type measurement comparisons, for instance. Typically, you might have clocks of various kinds. For instance, a nice quiet quartz oscillator has great phase noise, but does drift with time and temperature. So you could use that to measure the phase noise of something with not so hot performance. ___ 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-5680A Mechanical Question
On 1/13/12 2:24 PM, Hal Murray wrote: albertson.ch...@gmail.com said: and send the data out the GPIB but getting that into a computer is the hard part. OK so I check on eBay. Most are $300 but If you can find a computer with an old ISA slot then there are working GBIB cards for about $20. Many of us are happy with the Prologix. The USB version is $150. That's more than I really want to spend but less than $300 and you don't have to maintain an old PC. The USB version uses one of the popular USB-RS232 chips so there is no problem with drivers. I haven't tried the Ethernet version. I use the ethernet version at work. Love it. Mostly using Python, but shell scripts too. ___ 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-5680A Mechanical Question
$150 is $130 more than $20. It depends on if an ISA type computer shows up for free. I'm having doubts that one will. They seem to have become valuable. The machine would need to be at least a Pentium II so it could boot off the network and then mount some disk space. I know what you mean about maintenance so i don't want any disk inside and no OS installed. I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. Thanks, I just looked up the Prologix On Fri, Jan 13, 2012 at 2:24 PM, Hal Murray hmur...@megapathdsl.net wrote: albertson.ch...@gmail.com said: and send the data out the GPIB but getting that into a computer is the hard part. OK so I check on eBay. Most are $300 but If you can find a computer with an old ISA slot then there are working GBIB cards for about $20. Many of us are happy with the Prologix. The USB version is $150. That's more than I really want to spend but less than $300 and you don't have to maintain an old PC. The USB version uses one of the popular USB-RS232 chips so there is no problem with drivers. I haven't tried the Ethernet version. http://prologix.biz/ http://www.sparkfun.com/search/results?term=GPIBwhat=products -- 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. -- 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] FE-5680A Mechanical Question
GPIB is not realy slow by todays standars. It's still capable of transfering more data pr sec than USB 1, there is some notes about it at NI. The Prologix box consist of an an microcontroller and an USB chip or such, but the programming involved in order to get it all working is extencive if you want to support some of the early instruents. I use the Prologix USB box often. It appears as an serial port, and is easy to use. As fair as I understand, the GPIB-LAN device you just telnet into. BR. Thomas. 2012/1/13 Chris Albertson albertson.ch...@gmail.com $150 is $130 more than $20. It depends on if an ISA type computer shows up for free. I'm having doubts that one will. They seem to have become valuable. The machine would need to be at least a Pentium II so it could boot off the network and then mount some disk space. I know what you mean about maintenance so i don't want any disk inside and no OS installed. I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. Thanks, I just looked up the Prologix On Fri, Jan 13, 2012 at 2:24 PM, Hal Murray hmur...@megapathdsl.net wrote: albertson.ch...@gmail.com said: and send the data out the GPIB but getting that into a computer is the hard part. OK so I check on eBay. Most are $300 but If you can find a computer with an old ISA slot then there are working GBIB cards for about $20. Many of us are happy with the Prologix. The USB version is $150. That's more than I really want to spend but less than $300 and you don't have to maintain an old PC. The USB version uses one of the popular USB-RS232 chips so there is no problem with drivers. I haven't tried the Ethernet version. http://prologix.biz/ http://www.sparkfun.com/search/results?term=GPIBwhat=products -- 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. -- 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. -- Please avoid sending me Word or PowerPoint attachments. See http://www.gnu.org/philosophy/no-word-attachments.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.
Re: [time-nuts] FE-5680A Mechanical Question
On Fri, Jan 13, 2012 at 2:42 PM, Jim Lux jim...@earthlink.net wrote: On 1/13/12 2:33 PM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 2:19 PM,ewkeh...@aol.com wrote: Are we not overdoing it. 7E-13 for $15 KISS, and if you want to go beyond that use a $ 30 analog version. Looking right now at 1 E -14, I do se temperature influences, with my heat sink stable to .1 C. Mainly due to the fact that is only one side of the unit and it is clearly designed to use all sides for heat dissipation. Technical question, how does one measure 1E-14 changes in frequency? I'm thinking about building a controller and of course you can't control what you can't measure. But at that small level what do you use for a reference? Your other sources. Seriously.. Of course, the man who has two clocks doesn't know what time it is. If you have 3 sources, you can do three cornered hat type measurement comparisons, for instance. Typically, you might have clocks of various kinds. For instance, a nice quiet quartz oscillator has great phase noise, but does drift with time and temperature. So you could use that to measure the phase noise of something with not so hot performance. OK, in general I understand. But now we are talking about a $15 controller that needs to make a decision wetter to increment the DDS by 7E-13 or not. What is this controller looking at? People are already asking if people can write software and making PCB designs but first one needs to know basic things like: (1) what to use as a reference? (2) what kind of phase detector has the sensitivity to enable decisions at the e-13 level or e-14 level. (3) What time constants and loop gains would be reasonable (4) does the controller need input for temperature? (5) should the controller look at the saw tooth correction from the GPS (6) seems that a Kalman filter would help? Seems it could if you have a good temperature and aging model. Lots more I'm sure but basic requirements are needed before any design can begin. Hence my plan to use a desktop computer as the controller.I suspect the first few prototype solutions will not work well. 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] FE-5680A Mechanical Question
On Jan 13, 2012, at 17:51, Chris Albertson albertson.ch...@gmail.com wrote: I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. Several have. That is basically what the prologix is. There is another one you see on eBay quite often for about$60. The problem seems to be one of compatability and interpretation/implementation of the GPIB command set. For example, There is an NI gpib to USB as well, but it is not compatible with the Prologix. 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] RB ref FE 5086 $38 shipping included working fine out of the box with 5 V reg
Stabilizing now. Added the 5v 7805 included in the teddy bear and off it went. Follows current consumption as stated on the list. Still settling in compared to the ref thats been running so will see after a few hours. Clearly the 7805 needs a heat sink and I clamped a vice grip on for the moment. Regards Paul Wb8tsl ___ 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-5680A Mechanical Question
On 1/13/12 2:51 PM, Chris Albertson wrote: $150 is $130 more than $20. It depends on if an ISA type computer shows up for free. I'm having doubts that one will. They seem to have become valuable. The machine would need to be at least a Pentium II so it could boot off the network and then mount some disk space. I know what you mean about maintenance so i don't want any disk inside and no OS installed. I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. That's exactly what the Prologix is... a microcontroller that implements IEEE-488/GPIB with a command interface (serial port emulation with USB) Maybe what you mean is why has nobody published a design and software for free? ___ 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-5680A Mechanical Question
On 1/13/2012 5:37 PM, Chris Albertson wrote: What's bang-bang servo? (other than a techno band - http://www.myspace.com/bangbangservo ) A home thermostat is the best example. It is a servo with no proportional control, just on and off. So, is a common industrial PID controller, which only provides on/off control, but does so proportionally, bang-bang or not? It's significantly different than a thermostat, which just has hysteresis around a setpoint. ___ 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-5680A Mechanical Question
The controller looks at the 10 MHz from the Rb and a 1 Hz signal from either a GPS or a tbolt. Over the years I have been very happy with the Shera, except for the DAC. I control my Rb,s to .1 C. In a message dated 1/13/2012 6:06:05 P.M. Eastern Standard Time, albertson.ch...@gmail.com writes: On Fri, Jan 13, 2012 at 2:42 PM, Jim Lux jim...@earthlink.net wrote: On 1/13/12 2:33 PM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 2:19 PM,ewkeh...@aol.com wrote: Are we not overdoing it. 7E-13 for $15 KISS, and if you want to go beyond that use a $ 30 analog version. Looking right now at 1 E -14, I do se temperature influences, with my heat sink stable to .1 C. Mainly due to the fact that is only one side of the unit and it is clearly designed to use all sides for heat dissipation. Technical question, how does one measure 1E-14 changes in frequency? I'm thinking about building a controller and of course you can't control what you can't measure. But at that small level what do you use for a reference? Your other sources. Seriously.. Of course, the man who has two clocks doesn't know what time it is. If you have 3 sources, you can do three cornered hat type measurement comparisons, for instance. Typically, you might have clocks of various kinds. For instance, a nice quiet quartz oscillator has great phase noise, but does drift with time and temperature. So you could use that to measure the phase noise of something with not so hot performance. OK, in general I understand. But now we are talking about a $15 controller that needs to make a decision wetter to increment the DDS by 7E-13 or not. What is this controller looking at? People are already asking if people can write software and making PCB designs but first one needs to know basic things like: (1) what to use as a reference? (2) what kind of phase detector has the sensitivity to enable decisions at the e-13 level or e-14 level. (3) What time constants and loop gains would be reasonable (4) does the controller need input for temperature? (5) should the controller look at the saw tooth correction from the GPS (6) seems that a Kalman filter would help? Seems it could if you have a good temperature and aging model. Lots more I'm sure but basic requirements are needed before any design can begin. Hence my plan to use a desktop computer as the controller.I suspect the first few prototype solutions will not work well. 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. ___ 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] OT re, Sacramento River Monitor
Fellow nutters; A comment on something posted earlier today. I know this is off topic,(except for the time-stamp-GPS anteena comment ;-)) but the web site http://water.weather. gov/ahps/ lists all the hydrologic monitors around the county. There are two near here with the crossed yagis pointing at what I would imagine is some GOES satellite. These have solar panels, but I've not noticed a GPR antenna, perhaps I shall look a little closer next time I goes by them. Rich ___ 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-5680A Mechanical Question
On Fri, Jan 13, 2012 at 3:18 PM, Jim Lux jim...@earthlink.net wrote: On 1/13/12 2:51 PM, Chris Albertson wrote: $150 is $130 more than $20. It depends on if an ISA type computer shows up for free. I'm having doubts that one will. They seem to have become valuable. The machine would need to be at least a Pentium II so it could boot off the network and then mount some disk space. I know what you mean about maintenance so i don't want any disk inside and no OS installed. I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. That's exactly what the Prologix is... a microcontroller that implements IEEE-488/GPIB with a command interface (serial port emulation with USB) Maybe what you mean is why has nobody published a design and software for free? I've been Googling, Yes there is a free published. It appears to be the very much like the Prologix. The Prologix was the next iteration of this design. http://lpvo.fe.uni-lj.si/en/raziskave/elektronika/podatkovni-in-merilni-vmesniki/ 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] FE-5680A Mechanical Question
A PWM controller is bang-bang. Just means that the active drive has two states. The (usually) linear response of the system is provided by some kind of low-pass filtering in the controlled device. PID is a type of protocol used in the feedback loop. The feedback has a Proportional, an Integral, and a Derivative feedback element. A linear servo system has an output to the active element that is truly proportional to the error. It may or may not use a PID protocol in the loop. Example might be a current/voltage control for a dc motor. Filtered PWM is usually more efficient and less expensive as a controller than truly linear; the latter usually involves dumping energy somewhere. But, truly linear is capable of faster response times. You pays your money, etc. For example, as pointed out, the heating system in your house is run by a thermostat. This element. although linear, has trip points that simply turn the fan on and off. The air in the room(s) provides the low pass filter. So an on-off device drives the servo system that maintains the air temperature in the room at a constant value. In the Rb case, we seem to have (I have fired one up, but haven't been able to observe it much) a digital servo system to maintain the Rb physics package at a fixed frequency. The servo loop seems to have a least significant change value. The point here is that by applying PWM to the least significant bit, a smaller frequency change in the output can be implemented. One still has to develop an error signal that is sufficiently accurate to implement the PWM, and it's not known yet what the characteristics of the low-pass behavior of the unit is. Hope my simple exposition is clear and right; I did not mean to initiate an argument based on semantics rather than physics :-) Don Mike S On 1/13/2012 5:37 PM, Chris Albertson wrote: What's bang-bang servo? (other than a techno band - http://www.myspace.com/bangbangservo ) A home thermostat is the best example. It is a servo with no proportional control, just on and off. So, is a common industrial PID controller, which only provides on/off control, but does so proportionally, bang-bang or not? It's significantly different than a thermostat, which just has hysteresis around a setpoint. ___ 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. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. R. Bacon If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.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] Lady Heather S/W
On 01/13/2012 06:34 PM, Bob Camp wrote: Hi Lady Heather does not seem to like the Trimble CDMA units. That Lady Heather is one picky lady. It would be good if we could train her to dominate a larger audience,,, I would love to use here for my Z38xx clocks as well. 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.
Re: [time-nuts] Lady Heather S/W
I'm confused. Is there a Linux version of Lady Heather available? Or would I have to run it on WINE? ___ 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-5680A Mechanical Question
On 1/13/12 3:46 PM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 3:18 PM, Jim Luxjim...@earthlink.net wrote: On 1/13/12 2:51 PM, Chris Albertson wrote: $150 is $130 more than $20. It depends on if an ISA type computer shows up for free. I'm having doubts that one will. They seem to have become valuable. The machine would need to be at least a Pentium II so it could boot off the network and then mount some disk space. I know what you mean about maintenance so i don't want any disk inside and no OS installed. I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. That's exactly what the Prologix is... a microcontroller that implements IEEE-488/GPIB with a command interface (serial port emulation with USB) Maybe what you mean is why has nobody published a design and software for free? I've been Googling, Yes there is a free published. It appears to be the very much like the Prologix. The Prologix was the next iteration of this design. http://lpvo.fe.uni-lj.si/en/raziskave/elektronika/podatkovni-in-merilni-vmesniki/ Fascinating.. so basically, by spending $150 you save whatever time you'd spend buying the $50 worth of parts (which might be more by now) and assembling it. Seems a nice way to cover both ends of the user spectrum. ___ 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] FE-5650A Option CPOM Information
Looking for FE-5650A Rubidium Frequency Standard Information. I have obtained a FE-5650A unit that came out a piece of equipment made for Lucent, which I think is telco equipment. RFS Part # FE-5650A UN 62832, S/N 0404-71672 Option 5650A OPTION CPOM. The options do not match with anything I have been able to find. The unit requires +15V and +5Vdc on pin 4. It puts out a nice 3V pp wave form at very close to 15Mhz. I hope I can set unit up to put out 15.1Mhz threw a doubler to get 30.2Mhz for use with my IC-910 Radio. Anyone have any good/bad experience with this unit. I have been referred to the the following web page to try and program this unit over the RS-232 interface, this manual seems to apply to the FE-5680A series. I need to come up with a Serial TTL to RS232 converter as I can not see anything coming out of pin 9 with my scope and the unit does not have a Max232 chip that I can see.. ___ 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] Lady Heather S/W
It runs on Wine. Not 100% perfect but well enough to use it. If it is to do more, it needs a re-write. I'd like to see a few features (1) It should always run in client server mode. There is no reason to have the GUI and display talk to hardware directly. Then you can quit the GUI and still log data (2) Needs to be multi-platform. Should run native on most computers. Lots of ways to make that happen. cross platform GUI libraries, web based, ... (3) I would use a three tier design. You'd have three executable programs. They might all run on the same computer and you'd not have to know there were three but if you like you might distribute them onto two or three machines. The part would be: a) A basic server who's only job is to connect the GPS to TCP/IP so that the data can be sent over a network, wifi or wired or whatever. This is very simple and I might even be able to simply use gpsd and not have to write much http://www.catb.org/gpsd/ I think this server sould be simple enough tat it could run on a bare uP, AVR ir PIC that is connected to and Eithernet controller. All it does is time stamp and copy data. But it should also run on Windows, Linux, Mac and BSD b) A controller engine. This runs in the backgrond and contains all the logic for controlling GPSes and for logging data. Most all of what the program does in done here. There is no user interface, no screen display. casual used might not know the engine exists. c) Graphical user interface. This is a simple display and command input program that talks to the engine. There might even be several of these written. I could imagine one written as a native program for Windows and one in Java for multiple platforms and even an iPhone app. It talks over the network to the engine. But the above is a lot of work. First step is to re-build the windows binary code as a Linux native executable so that you don't need Wine. Easy why to do this is to compile with Wine library. Actually this is cheating because you end up with Wine embedded in the app. But it's a start. People will argue about programming languages and so on but I'd rater just build it in something that is VERY high level and free like scilab or something like it http://www.scilab.org/content/download/2187/22527/file/leaflet_Scilab.pdf On Fri, Jan 13, 2012 at 4:43 PM, Mike Naruta AA8K a...@comcast.net wrote: I'm confused. Is there a Linux version of Lady Heather available? Or would I have to run it on WINE? ___ 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] Lady Heather for a noob
On 01/13/2012 01:22 AM, Javier Herrero wrote: For providing ntp, probably the best way is to use ntp :) Ralph Smith did a good integration for BSD NTP. I patched it and wrote some startup and monitoring scripts for it for Ubuntu. See http://wa5znu.org/2011/08/tbolt/ I run Heather under Wine with some flags and make it talk to the server; that cuts way down on the CPU time that LH would otherwise use in its tight loops. Leigh/WA5ZNU ___ 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-5650A Option CPOM Information
Here's a start: http://www.leapsecond.com/museum/fei5650a/ Then: http://www.ko4bb.com/dokuwiki/doku.php?id=precision_timing:rubidium_oscillators Then google: 5650A site:febo.com On 1/13/2012 5:41 PM, Rich (Buckeye) wrote: Looking for FE-5650A Rubidium Frequency Standard Information. I have obtained a FE-5650A unit that came out a piece of equipment made for Lucent, which I think is telco equipment. RFS Part # FE-5650A UN 62832, S/N 0404-71672 Option 5650A OPTION CPOM. The options do not match with anything I have been able to find. The unit requires +15V and +5Vdc on pin 4. It puts out a nice 3V pp wave form at very close to 15Mhz. I hope I can set unit up to put out 15.1Mhz threw a doubler to get 30.2Mhz for use with my IC-910 Radio. Anyone have any good/bad experience with this unit. I have been referred to the the following web page to try and program this unit over the RS-232 interface, this manual seems to apply to the FE-5680A series. I need to come up with a Serial TTL to RS232 converter as I can not see anything coming out of pin 9 with my scope and the unit does not have a Max232 chip that I can see.. ___ 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-5680A Mechanical Question
I think lots of people have designed MCU based HPIB interfaces - the problem is that most of them are, like mine, designed to solve a specific problem and there is no subsequent incentive to clean up the documentation to the point where you wouldn't be embarrased to release it to the public - at least that's the state mine is in... On Jan 14, 2012 8:35 AM, Jim Lux jim...@earthlink.net wrote: On 1/13/12 3:46 PM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 3:18 PM, Jim Luxjim...@earthlink.net wrote: On 1/13/12 2:51 PM, Chris Albertson wrote: $150 is $130 more than $20. It depends on if an ISA type computer shows up for free. I'm having doubts that one will. They seem to have become valuable. The machine would need to be at least a Pentium II so it could boot off the network and then mount some disk space. I know what you mean about maintenance so i don't want any disk inside and no OS installed. I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. That's exactly what the Prologix is... a microcontroller that implements IEEE-488/GPIB with a command interface (serial port emulation with USB) Maybe what you mean is why has nobody published a design and software for free? I've been Googling, Yes there is a free published. It appears to be the very much like the Prologix. The Prologix was the next iteration of this design. http://lpvo.fe.uni-lj.si/en/**raziskave/elektronika/** podatkovni-in-merilni-**vmesniki/http://lpvo.fe.uni-lj.si/en/raziskave/elektronika/podatkovni-in-merilni-vmesniki/ Fascinating.. so basically, by spending $150 you save whatever time you'd spend buying the $50 worth of parts (which might be more by now) and assembling it. Seems a nice way to cover both ends of the user spectrum. __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://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-5680A Mechanical Question
I've found yet another good way to get data into a computer. Sparkfun sells a bundle with an Arduino and a student copy of Labview for $50 total. All the analog and digital pins are pulled into LabVIEW and then you can drag and drop the signals into processing blocks and connect those to graphs and plots. It's a very painless way to connect a graphic object on the computer screen to a pin on a uP. Labview is not a permanent solution but it's a quick way to experiment and build a sophisticated PID controller without writing any code. Then later write it in C and burn into the Arduino. Using Arduino costs more but I don't have to make a PCB and you can buy one the $20 on eBay. Also it would be very easy to add an Ethernet interface and SD card for data logging. You might say Ethernet and SD cards are to complex. But, no they plug in like a Lego block and don't cost much On Fri, Jan 13, 2012 at 9:50 PM, Peter Bell bell.pe...@gmail.com wrote: I think lots of people have designed MCU based HPIB interfaces - the problem is that most of them are, like mine, designed to solve a specific problem and there is no subsequent incentive to clean up the documentation to the point where you wouldn't be embarrased to release it to the public - at least that's the state mine is in... On Jan 14, 2012 8:35 AM, Jim Lux jim...@earthlink.net wrote: On 1/13/12 3:46 PM, Chris Albertson wrote: On Fri, Jan 13, 2012 at 3:18 PM, Jim Luxjim...@earthlink.net wrote: On 1/13/12 2:51 PM, Chris Albertson wrote: $150 is $130 more than $20. It depends on if an ISA type computer shows up for free. I'm having doubts that one will. They seem to have become valuable. The machine would need to be at least a Pentium II so it could boot off the network and then mount some disk space. I know what you mean about maintenance so i don't want any disk inside and no OS installed. I'm surprised that no one has built a GPIB controller from a uP. Electrically the GPIB is simple and slow by modern standards. That's exactly what the Prologix is... a microcontroller that implements IEEE-488/GPIB with a command interface (serial port emulation with USB) Maybe what you mean is why has nobody published a design and software for free? I've been Googling, Yes there is a free published. It appears to be the very much like the Prologix. The Prologix was the next iteration of this design. http://lpvo.fe.uni-lj.si/en/**raziskave/elektronika/** podatkovni-in-merilni-**vmesniki/http://lpvo.fe.uni-lj.si/en/raziskave/elektronika/podatkovni-in-merilni-vmesniki/ Fascinating.. so basically, by spending $150 you save whatever time you'd spend buying the $50 worth of parts (which might be more by now) and assembling it. Seems a nice way to cover both ends of the user spectrum. __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://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. -- 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.
