Re: [time-nuts] In the atomclock repairshop...
Nice article. Good to see a fellow 'Nut enjoying his hobby. ...now to brush up on my Swedish Have fun! Rob Kimberley -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Magnus Danielson Sent: 25 April 2012 20:06 To: Time-Nuts Subject: [time-nuts] In the atomclock repairshop... Fellow time-nuts, Oh, ok. So now it is public, so I better tell you about it... Jörgen Städje is a tech-writer which enjoys writing articles where he dips into some system and writes about it. Trying to teach things. Demystify things. So, when you read it, please recall that the audience is not very into the subject. It's in Swedish, but since you all know it by heart (or maybe using Babelfish) I think you surely enjoy it... http://www.idg.se/2.1085/1.443818/i-atomurmakarens-verkstad The photo-session was not all that well-planned, but enjoy the more intimate photos of among others my Russian CH1-78 / HG414A. Various splashes of instruments. One of the photos has direct inspiration from an LP. Extra points from identifying which album. :) Oh well. Hope you enjoy it for what it is. Hope you can handle the chock of seeing photos of me. Cheers, Magnus - another time-nut outed by a journalist ___ time-nuts mailing 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] PICTIC II ready-made?...nanode
On 26 April 2012 01:27, Chris Albertson albertson.ch...@gmail.com wrote: http://en.wikipedia.org/wiki/Raspberry_Pi I just read the above page. The Raspberry contains close source drivers and binary blob graphics firmware. That is an 100% deal killer. It's unfortunate that it makes use of binary drivers but Broadcom have a history of not being the best in this respect. However, I'm prepared to put up with this for a 700MHz ARM/Linux SBC for $25+VAT (if you don't need Ethernet). If someone else comes up with, say, a TI OMAP-based board for that price, great... But until then I'm not going to complain when the Broadcom SoC is making this price point possible... As to the GPU firmware — are there many modern GPUs where you get the source to their firmware? Regards, Andrew -- Andrew Back http://carrierdetect.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] PICTIC II ready-made?
Has any one considered asking Richard. As far as logic is concerned a 200 MHz Altera MAX 3000A makes a perfect substitute at a cost of $ 2.50 that includes a very solderable socket. Works Bert Kehren In a message dated 4/25/2012 3:16:51 P.M. Eastern Daylight Time, bruce.griffi...@xtra.co.nz writes: Chris Albertson wrote: On Wed, Apr 25, 2012 at 9:37 AM, Don Lathamd...@montana.com wrote: I forgot to add that a simple redrafting of the II as an Arduino shield with appropriate chips and chip passives would accomplish the desired end without losing the very careful engineering and testing that has already been done? Would be nice to have a way to change caps without soldering as well, maybe just some .1 jumpers? Yes, MOST of the design could be re-used. As an Arduino shield there is no need for a PIC or RS-232 interface becusethe Arduino does that function. You'd need to replace the 74ACT175 part but that is not hard. About changing the cap values without soldering. I guess you could push the leads into a 0.1 inch header strip or install several and use a DIP switch to select which are in. But I don't know if the extra inductance al that wiring adds is enough to worry about. The time to digital converter (TDC) section is merely an interpolator that measures the delay of a synchroniser. The TDC range should be about 2 clock periods to accommodate the range of synchroniser delays and to facilitate calibration. Unless one is changing the synchroniser clock period there is no need to vary the TDC gain. The SR620 uses a similar interpolator and has only a single interpolator range. The range is extended by counting the number of synchroniser clock periods between synchroniser output transitions of interest. When measuring the time interval between 2 signals a pair of synchronisers and interpolators are used. Interpolator nonlinearity can be measured by using a statistical fill the buckets technique which uses nothing but a pair of noisy asynchronous oscillators with high reverse isolation to avoid injection locking. If a suitable ADC is used the interpolator can be simplified considerably whilst improving its performance. Minor nonlinearities are of little significance, as long as they are repeatable and relatively stable they can be easily corrected in software. 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. ___ time-nuts mailing 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] Antique Rubidium Standard Questions
Some pix of the rg would be great On Wed, Apr 25, 2012 at 11:43 PM, Ed Palmer ed_pal...@sasktel.net wrote: Paul, Good suggestion, but I don't think pop rivets had been invented when they built this thing! :-D It's built like a piece of mil-spec equipment. When I google for individual parts, I keep tripping over NSN numbers. Now that I look closely at it, I realize that the case is just the case with no electrical connection between it and the circuit other than the BNC jacks on the front panel. The concept of 'chassis ground' is an unknown concept. I don't think there's even one chassis ground lug anywhere. Even when I'm poking around inside the unit, there are no live wires that I can touch, everything is insulated. The build quality is very high. But now that you've got me thinking about it, I think there's something weird about the grounding in the physics package. I've got to take another look at that. Thanks! Ed On 4/25/2012 8:59 PM, paul swed wrote: Ed look for pop rivetted ground logs. Famous for going bad. HP even used them. Drill em out and put real bolts and lock washers in On Tue, Apr 24, 2012 at 7:34 PM, Ed Palmered_pal...@sasktel.net wrote: Paul, On 4/24/2012 5:24 PM, paul swed wrote: When all else fails check the grounds. Especially 40 year old screws. Been there, done that. This unit had multiple problems with bad soldered ground connections. I went through the unit and resoldered everything that looked the least bit odd. I didn't find any screws that were electrically significant. Maybe I should look again! Ed On Tue, Apr 24, 2012 at 6:13 PM, ed breyae...@telight.com wrote: Ed, Tuning the cavity should peak everything - it just maximizes the excitation power at the microwave frequency, so you get the most output from the Rb light wavelengths. A mechanical cavity resonator will have a very wide (compared to the modulation frequencies you're looking for) bandwidth, so unless something happened to it physically, it should be OK as originally built or adjusted. However, you may want to look at the multiplier chain and SRD bias circuit components and adjustments - those could have drifted quite a bit over forty years, limiting the microwave power due to being off-frequency, or having poor multiplication efficiency. I'm guessing that the second harmonic is indeed present, but just buried in the noise, and the loop still can lock because of the further signal processing, even though you don't see the evidence - remember it's a lock-in amplifier capable of digging a tiny signal out of the noise. If you go through the multiplier and check and tweak things, you may get more excitation power and signs that it's getting back to normal. Once you get enough power, if the Rb cells are still good, the second harmonic signal should show up large enough for the circuit to detect sufficient S/N ratio and provide a valid lock indication. Ed Breya Ed Palmer wrote: Could the drift be at least partially responsible for the lack of second harmonic? A message on the list ( http://www.febo.com/**pipermail/time-nuts/2006-** April/020562.htmlhttp://www.febo.com/pipermail/time-nuts/2006-April/020562.html http://www.**febo.com/**pipermail/time-** nuts/2006-**April/020562.htmlhttp://www.febo.com/**pipermail/time-nuts/2006-**April/020562.html **) said that you could peak the second harmonic by adjusting the cavity tuning. If the cell and the cavity are out of sync would that kill the second harmonic? How close to they have to be? If this thing has a cavity tuning adjustment I haven't found it. __**_ 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] PICTIC II ready-made?
I have a friend who builds and sells power supply units that I designed. He may be interested in building some of these. If I had to guess, he'd be willing to build units and sell them on his web site. Who owns the IP for this project? Maybe we could get some input or direction... Contact me off list for more information... Thanks Dan On 4/25/2012 2:42 PM, time-nuts-requ...@febo.com wrote: Message: 1 Date: Wed, 25 Apr 2012 12:44:30 -0500 From: Stanleytimen...@n4iqt.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] PICTIC II ready-made? Message-ID:4795269806DF49A7B26877D7EB657063@StanleyPC Content-Type: text/plain; format=flowed; charset=iso-8859-1; reply-type=original I still have a supply of boards and most parts including the 74ac175 but no interest in assembly or the kitting process. If someone would like to take this on then I could provide the boards etc ... in bulk. Because of my limited space the kitting process takes several hours to do them one at time :-( Stanley ___ time-nuts mailing 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] In the atomclock repairshop...
Hi, On 26/04/12 10:53, Rob Kimberley wrote: Nice article. Good to see a fellow 'Nut enjoying his hobby. Oh yes, I do enjoy it. ...now to brush up on my Swedish Hej Rob, svenska är ju enkelt, eller hur? Have fun! As always. Thanks! 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] PICTIC II ready-made?...nanode
I tried to find a site to at least get the particulars for the Nanode. Sure it's not a Monode made of doped Nonobtanium? Alan Melia Mmmm not too impressive a web site thoughthe link to the buy page doesnt work backing up to the home the tabs in light grey on a white background are almost unreadabletoo must geewhizz and not the right HF input I suspectstill looks an interesting product. Alan G3NYK - Original Message - From: Andrew Back and...@carrierdetect.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Wednesday, April 25, 2012 7:39 PM Subject: Re: [time-nuts] PICTIC II ready-made? On 25 April 2012 19:09, Randy D. Hunt randy_hunt...@yahoo.com wrote: Then there is also the matter of surface mount components. Some people my not physically be able to work with them, learning to solder or not. I am rapidly joining that group be cause of my vision. Since Arduino has been mentioned I feel obliged to provide a link for Nanode, an Arduino-compatible that integrates Ethernet and low power wireless (e.g. 868MHz) for around the same price of an Arduino. It's supplied as a kit of through-hole components... http://wiki.london.hackspace.org.uk/view/Project:Nanode Or a nice alternative might be a daughterboard for a Raspberry Pi, which would give you an ARM/Linux base for not much more money, and you could use it to create a standalone system that drives an old monitor for a display. http://en.wikipedia.org/wiki/Raspberry_Pi Regards, Andrew -- Andrew Back http://carrierdetect.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] PICTIC II ready-made?
albertson.ch...@gmail.com said: 2) The IDE is written in Java and is portable. It is truly identical on all platforms. Yes it uses gcc but the end user never has to deal with gcc or even know what gcc is. Same with saving your code, hit just puts it some place and keeps track of it Do I have to use their particular style/GUI? Or can I drive it from make, mixing in pieces I like? How is the documentation on the tool chain and libraries? Are their good man pages? -- 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] Antique Rubidium Standard
On 26 April 2012 11:08, time-nuts-requ...@febo.com wrote: Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com Ed Palmer wrote: but I don't think pop rivets had been invented when they built this thing! :-D Just as a matter of interest, the humble pop-rivet was first patented in 1917 by Hamilton Neil Wylie, a Royal Navy Reservist and an improved version in 1927 when he was working for Armstrong-Whitworth, then a UK aircraft manufacturer. I don't think that the Quartz Crystal standard had been invented in 1917 Geoff -- # Geoff Blake, G8GNZ JO01fq: Chelmsford, Essex, UK ge...@palaemon.co.uk or melecert...@gmail.com Using Linux: Ubuntu 11.04 on Intel or Debian on UltraSparc and even on the NAS. Avoiding Micro$oft like the plague. # ___ time-nuts mailing 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] In the atomclock repairshop...
On 4/26/12 11:56 AM, Magnus Danielson wrote: Hi, On 26/04/12 10:53, Rob Kimberley wrote: Nice article. Good to see a fellow 'Nut enjoying his hobby. Oh yes, I do enjoy it. ...now to brush up on my Swedish And, since NASA pays my salary, at least indirectly, nice to see you wearing a shirt with a NASA logo on it... ___ time-nuts mailing 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] PICTIC II ready-made?
On 4/26/12 1:24 PM, Hal Murray wrote: albertson.ch...@gmail.com said: 2) The IDE is written in Java and is portable. It is truly identical on all platforms. Yes it uses gcc but the end user never has to deal with gcc or even know what gcc is. Same with saving your code, hit just puts it some place and keeps track of it Do I have to use their particular style/GUI? Or can I drive it from make, mixing in pieces I like? How is the documentation on the tool chain and libraries? Are their good man pages? The Arduino IDE is NOT make compatible, as far as I know.. The documentation is mostly wiki-like, as well as several books out there. Lots of online forums It's not like a gcc toolchain where you have a separate compiler, linker, binhex, etc and utilities.. It's an *integrated* development environment. If you want a free Java based cross platform IDE that is compatible with make and extensible, etc. look at Eclipse. It's what I use at work for (mostly) C development on Windows, Linux, and RTEMS targets (using cross compilers). It's VERY cool, there's tons of documentation, there's tons of useful plugins for lots of languages and capabilities (cvs, svn, git, etc.) What's nice is that the UI is really the same between my mac laptop, my windows desktop machine, and the linux boxes down in the lab (although, I confess that recently, I've been doing more ssh -X labmachine, because it's hooked up to the target). ___ time-nuts mailing 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] Sub mm measurements with gps timing antennas?
On 04/25/2012 07:05 PM, Tom Van Baak wrote: Hi Attila, Are you sure the customer said sub-mm and not sub-meter? I know post-processing is really helpful, but the LEA-6 is a single frequency receiver so all the advantage of L2 is lost for this customer. The bullet antenna's don't even have an arrow for North ;-) Actually, if you do both code and carrier phase you can make ionspheric measures on L1 alone. This is well known and documented, but I wonder how many actually attempts it. The thing is, the phase shift due to ionspheric dispersion has the same size, but different sign as you do code and carrier phase. What you can do is to resolve the bias between them and then make ionspheric observations and compensate for it. I've reported on this before, and Oncore VP receivers where used between a pair of caesium clocks. It would be a step up from carrier phase smoothed code measures. One thought -- seeing how this is a research project. It might be possible to cross-correlate the post-processed data against the Az-El of each SV along with ambient temperature over days or weeks and thus actually measure the phase center profile as well as tempco of the system. This would be no small effort, depending on the math and programming skills of the researcher(s), but the advantage for them is that is costs time instead of money. Then armed with this calibration data (possibly unique to each unit), it would be possible to reduce these effects, improving precision. I have no idea how much. Still, an interesting project. A simple test that could be done locally (refrigerator, sauna, etc.) would be to measure the tempco of the entire system (antenna, cables, LEA-6T) before they deploy it to a mountain. It may also be the case that the system has both a temperature coefficient and a temperature change coefficient so it's not a simple 2-point test. You can probably ignore humidity and barometric pressure. Another test would be to rotate the antenna at 1 RPH (revolution per hour) and then look for modulation in the post-processed solution. This would give a hint of the quality of the antenna. As a baseline, try the same test using a precision gps antenna. I have spare pin-wheel, choke-ring, and ground-plane antennas that I could loan, but surely these are available where you are, and probably cheaper than postage from here. It seems that everyone else that does sub-ns precision timing or mm positioning uses a large combination of tricks: dual-frequency antenna and receiver, geodetic-quality antenna, passive or active temperature control, phase-stabilized cables, GPS and Glonass, external frequency reference, and post-processing. Your customer is only using one from this long, expensive list. So there may be a lesson there. External frequency reference in terms of a rubidium should get you quite far in that regard, without much funds being used. Can you share any data they have collected already? I would be interested to know how far one could push a LEA-6T. That would be interesting. Getting one to play with would be fun. 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] Sub mm measurements with gps timing antennas?
On 04/25/2012 08:42 PM, Attila Kinali wrote: Moin, On Wed, 25 Apr 2012 10:05:00 -0700 Tom Van Baakt...@leapsecond.com wrote: Are you sure the customer said sub-mm and not sub-meter? I know post-processing is really helpful, but the LEA-6 is a single frequency receiver so all the advantage of L2 is lost for this customer. The bullet antenna's don't even have an arrow for North ;-) Yes, it is sub-mm. They are already doing sub-cm with the current setup, but it isn't precise enough yet. IIRC during the first tests last year they got4mm precision. And yes, using a LEA6-T with a Trimble Bullet antenna. I don't know what they actually do with the raw phase data, beside that they average over several hours and use a 100m baseline reference consisting of two stations mounted at a fixed position. One thought -- seeing how this is a research project. It might be possible to cross-correlate the post-processed data against the Az-El of each SV along with ambient temperature over days or weeks and thus actually measure the phase center profile as well as tempco of the system. This would be no small effort, depending on the math and programming skills of the researcher(s), but the advantage for them is that is costs time instead of money. Then armed with this calibration data (possibly unique to each unit), it would be possible to reduce these effects, improving precision. I have no idea how much. Still, an interesting project. Hmm.. That would be an idea, but i don't know whether it is feasible. Maybe i should here expand a little bit what the project actually is. The effort is part of the Permasense[1] Project, which does measurements of different parameters of permafrost soil/rock in high alpine regions. The idea of this sub-project is to measure the exact movement of rocks and other solid and unmovable things with regard to weather conditions. Beside the harsh environment, this also means that the devices cannot be reached for most of the year (there is usually a 3 months window when the devices can be accessed)..and some years they cannot access them at all (adverse weather conditions preventing ascend). For installation, a helicopter has to fly everything up into the mountains, which means that pre-assembled stuff cannot be transported, because it's too bulky (prevents whole system calibration in a climate chamber). After installation the system runs on solar power with a backup battery. But this doesn't guarrantee power at all. The solar panel could be below a meter or two of snow. Hence the whole system has to cope with periodic power los and has to be as low power as possible (ie no OCXO, no Rb, no temperature stabilization). The snow also prevents the use of choke rings, because they would accumulate a lot of snow and ice, which would then cover the whole antenna. If you buy the right choke rings, they come with a plastic cover with fairly steep slopes, so snow-buildup would not be dramatic. Just bring it up from the ground with good support. But at least, there is hardly any electronic interference, a good sky view (no trees), unless the system is mounted near a wall. And the antenna cable is quite short (it was 15cm in the previous version of the device and should be50cm in the next) You get a well defined phase-center, and also known. You can then bring in calibration files and reduce the phase-center in the post-processing. This is standard stuff, and there is plenty of information online on it. Consider that the C/A code has a rate of 1,023 Mchip/s, so anything within 150m will not be de-correlated by the C/A code. Here is another benefit of the P(Y) recievers, they bring this into 15m radius. A simple test that could be done locally (refrigerator, sauna, etc.) would be to measure the tempco of the entire system (antenna, cables, LEA-6T) before they deploy it to a mountain. It may also be the case that the system has both a temperature coefficient and a temperature change coefficient so it's not a simple 2-point test. You can probably ignore humidity and barometric pressure. I think the ETH has climate chambers that could run such tests. But i'm not sure how you'd test the antenna in such a chamber. 1) Network analyzer measuring phase delay and group delay in the range of interest. 2) GPS simulator times from a rubidium, and then compare how timing deviates. Another test would be to rotate the antenna at 1 RPH (revolution per hour) and then look for modulation in the post-processed solution. Hmm.. that's actually a quite nice test. Cool idea, thanks! This would give a hint of the quality of the antenna. As a baseline, try the same test using a precision gps antenna. I have spare pin-wheel, choke-ring, and ground-plane antennas that I could loan, but surely these are available where you are, and probably cheaper than postage from here. Yes. The problem is, antennas that perform well in a city environment, where temperature swings are quite limited, fail in
Re: [time-nuts] In the atomclock repairshop...
On 04/26/2012 11:48 PM, Jim Lux wrote: On 4/26/12 11:56 AM, Magnus Danielson wrote: Hi, On 26/04/12 10:53, Rob Kimberley wrote: Nice article. Good to see a fellow 'Nut enjoying his hobby. Oh yes, I do enjoy it. ...now to brush up on my Swedish And, since NASA pays my salary, at least indirectly, nice to see you wearing a shirt with a NASA logo on it... Hehe, yes. They had an exhibit touring the world that started in Stockholm, so I was there on the last weekend. I just pulled the next t-shirt in the pile that morning, so it was not on intention. So far NASA hasn't sponsered me in any way, except for the helping hand of a few researchers, but I'm sure I could make room for a spare H-maser or so. ;-) 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] Antique Rubidium Standard
Wow! I stand corrected. I had no idea that they were that old. Thanks, Ed On 4/26/2012 3:20 PM, Geoff Blake wrote: Ed Palmer wrote: but I don't think pop rivets had been invented when they built this thing! :-D Just as a matter of interest, the humble pop-rivet was first patented in 1917 by Hamilton Neil Wylie, a Royal Navy Reservist and an improved version in 1927 when he was working for Armstrong-Whitworth, then a UK aircraft manufacturer. I don't think that the Quartz Crystal standard had been invented in 1917 Geoff ___ time-nuts mailing 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] Antique Rubidium Standard Questions
I wondered if anyone would ask for pictures. They'll be ready soon. Ed On 4/26/2012 6:21 AM, paul swed wrote: Some pix of the rg would be great On Wed, Apr 25, 2012 at 11:43 PM, Ed Palmered_pal...@sasktel.net wrote: Paul, Good suggestion, but I don't think pop rivets had been invented when they built this thing! :-D It's built like a piece of mil-spec equipment. When I google for individual parts, I keep tripping over NSN numbers. Now that I look closely at it, I realize that the case is just the case with no electrical connection between it and the circuit other than the BNC jacks on the front panel. The concept of 'chassis ground' is an unknown concept. I don't think there's even one chassis ground lug anywhere. Even when I'm poking around inside the unit, there are no live wires that I can touch, everything is insulated. The build quality is very high. But now that you've got me thinking about it, I think there's something weird about the grounding in the physics package. I've got to take another look at that. Thanks! 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] PICTIC II ready-made?
On Thu, Apr 26, 2012 at 1:24 PM, Hal Murray hmur...@megapathdsl.net wrote: albertson.ch...@gmail.com said: 2) The IDE is written in Java and is portable. It is truly identical on all platforms. Yes it uses gcc but the end user never has to deal with gcc or even know what gcc is. Same with saving your code, hit just puts it some place and keeps track of it Do I have to use their particular style/GUI? Or can I drive it from make, mixing in pieces I like? How is the documentation on the tool chain and libraries? Are their good man pages? The tools are pretty much the standard GCC, and then avrdude. It's all open source. But if you are going to do this your self why not simply use a bare AVR chip? Documentation of the libraries is very good. First their is the Adruino web site which is enough if you already had a preference for tools. Then their are dozens of books you can find. Go to Amazon.com and search for Arduino. Man Pages??? that is a command line thing from the previous century, docs now days are in HTML 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] PICTIC II ready-made?
On Thu, Apr 26, 2012 at 12:20 PM, Don Latham d...@montana.com wrote: OK, Chris, I'll bite. What the heck is a tool chain? It is the series (or chain) of software tools you need to use. Text editor, compiler, linker and whatever you need to program the chip and then maybe a debugger and maybe version control With Arduino there is no chain got the one Java program. Wellit calls other stuff but most users never notice. 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] PICTIC II ready-made?
Hal Murray hmurray@... writes: albertson.chris@... said: 2) The IDE is written in Java and is portable. It is truly identical on all platforms. Yes it uses gcc but the end user never has to deal with gcc or even know what gcc is. Same with saving your code, hit just puts it some place and keeps track of it Do I have to use their particular style/GUI? Or can I drive it from make, mixing in pieces I like? You can use make, as does my project. In fact, I have a system that compiles the bulk of the project twice; once for the Arduino, and once in a simulator harness where I can test things like the PLL response. How is the documentation on the tool chain and libraries? Are their good man pages? The toolchain is of course avr-gcc and avr-binutils, and the library is mostly avr-libc, which is very well documented; the remainder is the Arduino libraries, which are in C++ and have mediocre (but existent, at least) documentation. I'd like to point out that using the Arduino libs is *optional*; while the main target audience certainly will be using them, there's nothing about the hardware that prevents you from writing code in plain C and uploading it, or picking and choosing which parts of a project will make use of the Arduino libs and which will access the bare metal. Again, I've done this with my project. The Serial library is pleasant enough to use; the Ethernet is marginal (no interrupt support, but I had an easier time hacking around that than attempting to rewrite the driver); the timing code is of course useless for my purposes so I stay away from it. I never call attachInterrupt(), which involves a trampoline, but instead declare my own ISRs -- the mixing is mostly unproblematic. It's been pretty pleasant for me overall. Andrew ___ time-nuts mailing 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] Antique Rubidium Standard Questions
Nothing like looking at the ole antiques On Thu, Apr 26, 2012 at 6:49 PM, Ed Palmer ed_pal...@sasktel.net wrote: I wondered if anyone would ask for pictures. They'll be ready soon. Ed On 4/26/2012 6:21 AM, paul swed wrote: Some pix of the rg would be great On Wed, Apr 25, 2012 at 11:43 PM, Ed Palmered_pal...@sasktel.net wrote: Paul, Good suggestion, but I don't think pop rivets had been invented when they built this thing! :-D It's built like a piece of mil-spec equipment. When I google for individual parts, I keep tripping over NSN numbers. Now that I look closely at it, I realize that the case is just the case with no electrical connection between it and the circuit other than the BNC jacks on the front panel. The concept of 'chassis ground' is an unknown concept. I don't think there's even one chassis ground lug anywhere. Even when I'm poking around inside the unit, there are no live wires that I can touch, everything is insulated. The build quality is very high. But now that you've got me thinking about it, I think there's something weird about the grounding in the physics package. I've got to take another look at that. Thanks! Ed __**_ 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] Z3801A Power Connector
I unexpectedly came into a small supply of the 3-pin Universal Mate-N-Lock connectors that plug into the power connector on the rear panel of the HP Z3801A GPSDO. If you need one of these and can't readily find it locally, contact me off-list. -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ time-nuts mailing 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] PICTIC II ready-made?
On 27 Apr, 2012, at 02:57 , Chris Albertson wrote: Closed source drivers and binary blob firmware.I'd have nothing to do with a project that includes either of those. I'd require a open source platforms with a 100% free tool chain. Also, it is a bit of overkill after all a bare PIC works fine for this application. The only thing binary blob about the Raspberry Pi that I can see seems to be the stuff associated with the graphics accelerator. This is unfortunate, but unless you are into bare-metal programming of high resolution graphics/video (you can do that with an Arduino?) I'm not quite sure how that is relevant. The programming interfaces for all peripherals on the SoC not associated with the GPU seem to be well documented in the Broadcom data sheet: http://www.designspark.com/files/ds/supporting_materials/Broadcom%20BCM2835.pdf I don't know of anything useful which is missing, and I know a port of a non-Linux operating system (NetBSD) to the board is being done using nothing that is non-public. You can leave the graphics binary blob out if you find that offensive and have no use for it anyway. I think the most annoying thing about the Raspberry Pi is that a lot of the GPIO signals aren't brought out to connectors, perhaps to save money on the board. Dennis Ferguson ___ time-nuts mailing 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] PICTIC II ready-made?
On Thu, 26 Apr 2012 14:58:26 -0700, Jim Lux wrote: On 4/26/12 1:24 PM, Hal Murray wrote: albertson.ch...@gmail.com said: 2) The IDE is written in Java and is portable. It is truly identical on all platforms. Yes it uses gcc but the end user never has to deal with gcc or even know what gcc is. Same with saving your code, hit just puts it some place and keeps track of it Do I have to use their particular style/GUI? Or can I drive it from make, mixing in pieces I like? How is the documentation on the tool chain and libraries? Are their good man pages? The Arduino IDE is NOT make compatible, as far as I know.. The Arduino IDE is basically an advanced JAVA Editor , that hides avr-gcc for you. The IDE part is that it knows how/where to include/look for the CPP libraries. It's not like a gcc toolchain where you have a separate compiler, linker, binhex, etc and utilities.. It uses a 100% standard avr-gcc toolchain as backend , and just creates the commandline call for using that. So avr-gcc , avr-as , avr-ar , avr-objcopy etc. are used behind the curtains. For uploading the program , it uses avrdude. And expects a STK-500 V1 (the old protocol) bootloader to be installed in the chip. Make compatible . Well it's a bit of a challenge to use make , as you have to tell/teach make about the location of the libraries. That the IDE java code already knows about . But it's certainly possible. As i see it : Arduino HW is a standard AVR microprocessor board , that can be used with any editor/compiler. The thing that makes the HW Arduino compatible is the installing of the bootloader. So take any ATmega328 board with a 16Mhz Xtal (The libs expect 16Mhz). Install the bootloader , add a serial interface. And you have an Arduino. The main advantage of the Arduino layout , is that anyone can walk into a RadioSchack and buy one. No soldering required , if one wishes that. As there is a bootloader installed you don't need to have an AVR-ISP programmer , the programming is done via Serial RS-232. So all you need is a COM-Port/ttyxx on your pc. The other advantage is that there are so many premade/downloadable libraries out there , that you can make : ie. a PID controller wo. knowing much about PID. And you can add a Temp sensor a LCD wo. ever having opened a datasheet. The disadvantage is that due to the hiding/hw-abstraction layer , the generated standard librarycode tends to be slow. But in many cases ie. a DS1820B temp sensor can only make a measurement every 700 ms. So who cares if the 16Mhz was able to query it 1000 times/ sec , in optimized C. But absolutely nothing prevents you to , combine your own Optimized C / asm code , with the arduino libraries. And get the best from both worlds. CFO - Denmark (Bingo on AVRFreaks.net) ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
