[time-nuts] IRIG-B with Arduino
If you didn´t started yet, you may consider the PSoC series of Cypress semiconductors. They contain digital and analog resources within the chip, simplifying the hardware design – and hardware changes. The new design, PsoC 5, is based on the ARM architecture, up to 256KB code and 64kB data, support for USB, the usual peripherals plus PLDs, OpAmps, and other analog devices. The starter kit is very affordable (US$48.88 on DigiKey). A version is planned in 48 pins SSOP – soldering is not as easy as dip, but doable. Even the 100 pin TQFP is solderable – QFN is another story… -- Geraldo Lino de Campos gera...@decampos.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.
Re: [time-nuts] FW: E5500 phase noise test set
Hi Clive, The PCI card was not made by HP. see http://control.etfbl.net/mjerenja/pci20428w.pdf for the manual. It's a multi-purpose card so you need to know which inputs (or outputs) are used. The HP system description may help. Otherwise you will have to get someone with the adaptor to do a continuity check on it. Or play a guessing game. Put a 'scope on the main unit and see it it has analogue or TTL signals and start from there. Regards, Robert G8RPI. --- On Wed, 15/12/10, Clive Green cgr...@quartzlock.com wrote: From: Clive Green cgr...@quartzlock.com Subject: [time-nuts] FW: E5500 phase noise test set To: time-nuts@febo.com Date: Wednesday, 15 December, 2010, 12:03 Subject: Fw: E5500 phase noise test set I have recently started to put together a used E5500B phase noise test set. I have bought the main unit, the 70420A test set, from the USA and have got this to work with an GPIB card. I have also bought a used PCI-20428W-1 digitizer card which the system recognises OK. My problem is that the card needs an adapter from the 50 way connector on the card to 2 SMA coaxial connectors which go to the test set. There is a picture of this in the installation manual which I have attached. Attempts to get information on this from Agilent have completely failed as they no longer use the PCI-20428W card, and the adapter is long since obsolete. If is has the adapter, does someone have photos of the inside of it, and/or perhaps trace the connections between the SMA connectors and the card connector. Once I have this information, I am sure I can make another adapter. Clive G3OPX/MM (soon) cgr...@quartzlock.com -Inline Attachment Follows- ___ 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] FW: E5500 phase noise test set
The link didn't work, so I searched for PCI20428 and found this: http://www.bedogmbh.de/seite5010.htm (scroll down to find the card) Worst case you can buy a break-out box: http://www.bedogmbh.de/seite1412.php http://www.bedogmbh.de/pdf/22101035.pdf I'm not affiliated with them. Recently I saw that adapter on ePay, but I don't remember the seller, so that is probably of no help, I'm afraid. Btw. do you have the system software? Adrian Robert Atkinson schrieb: Hi Clive, The PCI card was not made by HP. see http://control.etfbl.net/mjerenja/pci20428w.pdf for the manual. It's a multi-purpose card so you need to know which inputs (or outputs) are used. The HP system description may help. Otherwise you will have to get someone with the adaptor to do a continuity check on it. Or play a guessing game. Put a 'scope on the main unit and see it it has analogue or TTL signals and start from there. Regards, Robert G8RPI. --- On Wed, 15/12/10, Clive Greencgr...@quartzlock.com wrote: From: Clive Greencgr...@quartzlock.com Subject: [time-nuts] FW: E5500 phase noise test set To: time-nuts@febo.com Date: Wednesday, 15 December, 2010, 12:03 Subject: Fw: E5500 phase noise test set I have recently started to put together a used E5500B phase noise test set. I have bought the main unit, the 70420A test set, from the USA and have got this to work with an GPIB card. I have also bought a used PCI-20428W-1 digitizer card which the system recognises OK. My problem is that the card needs an adapter from the 50 way connector on the card to 2 SMA coaxial connectors which go to the test set. There is a picture of this in the installation manual which I have attached. Attempts to get information on this from Agilent have completely failed as they no longer use the PCI-20428W card, and the adapter is long since obsolete. If is has the adapter, does someone have photos of the inside of it, and/or perhaps trace the connections between the SMA connectors and the card connector. Once I have this information, I am sure I can make another adapter. Clive G3OPX/MM (soon) cgr...@quartzlock.com -Inline Attachment Follows- ___ 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] IRIG-B with Arduino
FWIW, if you're looking for a cheap, very capable AVR dev board. i've had very good success with the Teensy. You can use AVR-GCC or assembler but it has an Arduino compatibility layer if thats your thing. http://pjrc.com/teensy/index.html they're cheap and easy to work with, US made, and have great support and example code, and is breadboard/through hole friendly -Eric On Tue, Dec 14, 2010 at 10:19 PM, Bruce Lane kyr...@bluefeathertech.com wrote: Fellow clock-tickers, I'm finally starting to learn microcontrollers, and have selected Atmel's AVR line as my tool of choice. I've also discovered the Arduino site, and am starting to learn their IDE as well. My first goal will be an open-source/open-hardware IRIG-B decoder (takes IRIG-B 1kHz stream, sends the timecode to an LCD panel). I've noticed a distinct lack of hobby-priced decoders on the market, and I intend to try and remedy that. My initial development platform will be the Arduino Mega-2560 board. However, that particular microcontroller is unlikely to be my final chip of choice due to the fact it's not available in a hobbyist-friendly DIP package. If others with more development skill have suggestions for a different chip, I will gladly listen. Stay tuned for further developments (no pun intended). I expect this to take at least a few months, as the learning curve looks kind of steep. -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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. -- --Eric _ Eric Garner ___ 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] FW: E5500 phase noise test set
Sorry, I purchased the adapter for a system we were putting together. Agilent still has some for $500, a bit extravagant for my tastes. The interface board is made by Intelligent Instrumentation in AZ. The license for the 5500 is based on the serial number of the 70420A and is a lifetime license from what I understand. I do have copies of the software and I think it's available from Agilent's website. Thanks, Richard Parrish Cal Center Inc 1622 Griffith Ave Terrell, Texas 75160-4905 calc...@swbell.net 214-577-3515 -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Adrian Sent: Wednesday, December 15, 2010 6:50 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FW: E5500 phase noise test set The link didn't work, so I searched for PCI20428 and found this: http://www.bedogmbh.de/seite5010.htm (scroll down to find the card) Worst case you can buy a break-out box: http://www.bedogmbh.de/seite1412.php http://www.bedogmbh.de/pdf/22101035.pdf I'm not affiliated with them. Recently I saw that adapter on ePay, but I don't remember the seller, so that is probably of no help, I'm afraid. Btw. do you have the system software? Adrian Robert Atkinson schrieb: Hi Clive, The PCI card was not made by HP. see http://control.etfbl.net/mjerenja/pci20428w.pdf for the manual. It's a multi-purpose card so you need to know which inputs (or outputs) are used. The HP system description may help. Otherwise you will have to get someone with the adaptor to do a continuity check on it. Or play a guessing game. Put a 'scope on the main unit and see it it has analogue or TTL signals and start from there. Regards, Robert G8RPI. --- On Wed, 15/12/10, Clive Greencgr...@quartzlock.com wrote: From: Clive Greencgr...@quartzlock.com Subject: [time-nuts] FW: E5500 phase noise test set To: time-nuts@febo.com Date: Wednesday, 15 December, 2010, 12:03 Subject: Fw: E5500 phase noise test set I have recently started to put together a used E5500B phase noise test set. I have bought the main unit, the 70420A test set, from the USA and have got this to work with an GPIB card. I have also bought a used PCI-20428W-1 digitizer card which the system recognises OK. My problem is that the card needs an adapter from the 50 way connector on the card to 2 SMA coaxial connectors which go to the test set. There is a picture of this in the installation manual which I have attached. Attempts to get information on this from Agilent have completely failed as they no longer use the PCI-20428W card, and the adapter is long since obsolete. If is has the adapter, does someone have photos of the inside of it, and/or perhaps trace the connections between the SMA connectors and the card connector. Once I have this information, I am sure I can make another adapter. Clive G3OPX/MM (soon) cgr...@quartzlock.com -Inline Attachment Follows- ___ 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] Adjusting accuracy of a Casio G-Shock watch
Hi Jim: It may not be a good idea to adjust the watch so that the frequency is spot on at the time the adjustment is made. A better idea may be to wear the watch for a week and note the fractional time error then adjust the frequency so the offset matches the error. Have Fun, Brooke Clarke http://www.PRC68.com Jim Palfreyman wrote: Fellow time-nuts. Over in another part of the internet is a group of people who love their Casio G-Shock watches. These digital watches have been around for decades and are built very well. The one I own is an atomic and solar model (i.e. no battery replacement). However being in Tasmania, I cannot receive the low frequency time signals. When I first received the watch it's accuracy was excellent. Under 10 seconds a year. I even posted on here about it. Since then though it has drifted somewhat. After a ton of internet searching on how to open the case and how to adjust these watches (this is non trivial as the models are all very different and no instructions existed for this model - the GW-810D) I have finally cracked it. Interestingly, the module has a pad that gives off a stepped square wave at 32768/48 Hz. So with well calibrated equipment (which we all have of course) it is trivial to adjust the trimmer to put the watch back to decent accuracy. Using the smallest adjustment of the trimmer that I could muster I could get it down to about 0.5 in 10^6 or 1 second in around 20 days. Not as good as when I got it - but I was probably just lucky. Over in mygshock.com they struggle with this sort of timing stuff - whereas my big deal was opening the case! Just posting in this in case anyone here is interesting in adjusting their G-Shock. Jim ___ 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] Frequency counter recommendation
I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. Thanks for advice, David dgminala at mediacombb dot 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.
Re: [time-nuts] Frequency counter recommendation
I suspect that this question will lead to a discussion of Dual Mixers but as far as the counter question goes, I would recommend you consider an HP 5370B. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on Behalf Of Dave M Sent: Wednesday, December 15, 2010 1:55 PM To: TimeNuts Subject: [time-nuts] Frequency counter recommendation I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. Thanks for advice, David dgminala at mediacombb dot 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. - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1170 / Virus Database: 426/3317 - Release Date: 12/15/10 ___ 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] TAC/TDC
On Wed, Dec 15, 2010 at 8:15 AM, Josef Kölbl josef.koe...@fh-deggendorf.dewrote: Bob, yes, building a TDC/TAC is not a problem. Thanks. Josef We have been asked to develop a TDC card in FMC (VITA 57) form factor. In principle we plan to use ACAM's TDC-GPX, but our specs are much more relaxed: http://www.ohwr.org/projects/fmc-tdc/wiki Cheers, 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] Frequency counter recommendation
OK, time-nuts, here's the gauntlet. can't we generate a design for a PC-based FPGA or chip setup that would be generally useful as a counter? We've seen thorough discussions about trigger jitter, which IMHO is the fundamental problem. And isn't the PIC2 Time base from 10 MHz standard, all else should be straightforward. I'm not a designer, just a messer-arounder, or I'd give it a shot. Robot Basic is a nice PC software maybe. Don J. L. Trantham, M. D. I suspect that this question will lead to a discussion of Dual Mixers but as far as the counter question goes, I would recommend you consider an HP 5370B. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on Behalf Of Dave M Sent: Wednesday, December 15, 2010 1:55 PM To: TimeNuts Subject: [time-nuts] Frequency counter recommendation I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. Thanks for advice, David dgminala at mediacombb dot 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. - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1170 / Virus Database: 426/3317 - Release Date: 12/15/10 ___ 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] Frequency counter recommendation
Hello Dave, Others will have better suggestions for the time interval measurement equipment. My suggestion is to consider the Prologix GPIB to USB adapter for ~150$ brand new stock. I wasted some time with a NI controller and an older HP adapter before I got the Prologix. I never looked back. Stan, W1LECape Cod On 12/15/2010 2:55 PM, Dave M wrote: I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. ___ 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] Frequency counter recommendation
Hi Dave, On 12/15/2010 08:55 PM, Dave M wrote: I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. A HP5370A/B and a Prologix USB-GPIB interface seems like a popular solution, and it should fit inside your budget more or less. There is already software available (from John Miles for instance) that works with that solution, but it should also allow yourself some programming exercises. This will certainly get you started. There are several decades to go down into the noise for the really good sources and reducing measurement noise. It will be a fairly good solution for many decent sources. Grab a copy of the NIST SP 1065 and ponder over it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] TAC/TDC
On 12/15/2010 08:13 AM, Josef Kölbl wrote: Magnus, with regard to your questions: measurement rate = 1 kHz rms jitter = 10 ps linearity better 3 ps resolution of 1 ps is the minimum differential measurement which can be made (ie granularity). Thanks, this makes your requirements much clearer. This does not seem to be within reach of the ACAM devices and the PICTIC II is not in that neightborhood either: http://www.thegleam.com/ke5fx/pictic.htm Considering the 25 ns maximum TI difference (if I recall your specs correctly) it would require a 16 bit ADC besides good input. I doubt that you would find a complete solution lying around, but either you revamp the PICTIC II concept or go for some other variant of time interpolation. Maybe Bruce may give some suitable advice. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Modulation Analyzer to measure Phase Noise ?
Hi, How good can be a Modulation Analyzer (such as the RS FAM, which I happen to have one) for measuring phase noise? Since it measures phase modulation, it should be able to somehow measure phase noise, right?. Assuming it is using a low noise reference, how useful is it for roughly comparing phase noise of relatively clean 10Mhz oscillators? What are the best settings, regarding detector type and filters? I uploaded the FAM specs here, just in case someone wants to check them: http://www.rbarrios.com/public/FAM_specs.pdf Thank you, Roberto EB4EQA ___ 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] Adjusting accuracy of a Casio G-Shock watch
Hi Brooke, I've adjusted the watch as best I can within the limitations of the trimmer. The waveform was drifting 10 microseconds (slow) in about 20 seconds and so this should come out to 1 second in 23 days. I have now set the watch accurately and will follow it's progress. I plan to see how long it takes to be a second out and then re-open the cover and re-check the wave form. From that I should be able to work out the relationship between the measured frequency and actual watch accuracy. Watch (*cough cough*) this space. :-) Jim P.S. I'm so looking forward to being able to have a genuine atomic watch on my wrist. Surely it can't be too far away... On 16 December 2010 06:03, Brooke Clarke bro...@pacific.net wrote: Hi Jim: It may not be a good idea to adjust the watch so that the frequency is spot on at the time the adjustment is made. A better idea may be to wear the watch for a week and note the fractional time error then adjust the frequency so the offset matches the error. Have Fun, Brooke Clarke http://www.PRC68.com Jim Palfreyman wrote: Fellow time-nuts. Over in another part of the internet is a group of people who love their Casio G-Shock watches. These digital watches have been around for decades and are built very well. The one I own is an atomic and solar model (i.e. no battery replacement). However being in Tasmania, I cannot receive the low frequency time signals. When I first received the watch it's accuracy was excellent. Under 10 seconds a year. I even posted on here about it. Since then though it has drifted somewhat. After a ton of internet searching on how to open the case and how to adjust these watches (this is non trivial as the models are all very different and no instructions existed for this model - the GW-810D) I have finally cracked it. Interestingly, the module has a pad that gives off a stepped square wave at 32768/48 Hz. So with well calibrated equipment (which we all have of course) it is trivial to adjust the trimmer to put the watch back to decent accuracy. Using the smallest adjustment of the trimmer that I could muster I could get it down to about 0.5 in 10^6 or 1 second in around 20 days. Not as good as when I got it - but I was probably just lucky. Over in mygshock.com they struggle with this sort of timing stuff - whereas my big deal was opening the case! Just posting in this in case anyone here is interesting in adjusting their G-Shock. Jim ___ 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] TAC/TDC
On Wed, Dec 15, 2010 at 10:49 PM, Magnus Danielson mag...@rubidium.dyndns.org wrote: ... http://www.ohwr.org/projects/fmc-tdc/wiki Hmm. How do you intend to discriminate short pulses? It needs to be done in a way that it does not significantly impairs on the timing measurement. The TDC chip will give the FPGA a measurement but it will be ignored, i.e. not stored in the circular buffer. This would mean the FPGA would need to get its own copy of the input pulses to check for width violations. At the precisions we are considering we could probably use a standard fanout chip. Time-stamping wrap-around requirement is not in the spec. Essentially a requirement on the length of the time-stamping counter. Thanks, I made that 64 bits. You mix requirements and sketch of design-idea. Keep requirements and proposed design properties separate. Granted. It's a very young project. We will clean up soon. Cheers, 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] TAC/TDC
Just finished editing 25 papers on process control for FDA (Food and Drug Administration) regulated industries, so here are a few reflexive neuron firings. The FDA requires that the user requirements be captured first, in a way that can be understood by both the user and the vendor of the required hardware or software, but with no vendor contribution. Once agreement has been reached, the vendor prepares a functional specification that can be understood by the user and the people who will build the thing that is proposed. When the functional specification is approved, the technical team prepares design requirements and builds what the user needs (they hope). When built, it is tested against the design specification, then the functional spec, and finally the user spec. The user signs off on the last tests to accept the product. This only works when everybody is on familiar ground, and all of the technical principles (if not the details) are understood. Otherwise, you enter a design, prototype, and feedback cycle until the user and the vendor can agree on what the vendor will provide. Only then can the user write requirements that don't require transmutation of elements or time travel. Concisely, the requirements must refer to feasible design properties. They can't be kept separate until it is known that the thing can be done. After that, the FDA process (V-Model) assures a win-win result, if you have the people and the time to handle the documentation and negotiations. All IMHO, of course. Bill Hawkins -Original Message- From: Magnus Danielson Sent: Wednesday, December 15, 2010 3:50 PM %-- You mix requirements and sketch of design-idea. Keep requirements and proposed design properties separate. 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] Frequency counter recommendation
I just went thru a similar process and recently acquired a HP 5370B (my best prior counter was also a HP 5328.) I pondered some of the other choices such as the HP 5334 but decided to jump ahead to the HP 5370B. Also thanks again for the advice from members of the list and I found lost of usefull insight by searching the list archives. So far I've been pleased with my choice. I still like the HP 5328 as a general purpose bench counter. Regards Mark S - Original Message From: Magnus Danielson mag...@rubidium.dyndns.org To: time-nuts@febo.com Sent: Wed, December 15, 2010 1:14:45 PM Subject: Re: [time-nuts] Frequency counter recommendation Hi Dave, On 12/15/2010 08:55 PM, Dave M wrote: I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. A HP5370A/B and a Prologix USB-GPIB interface seems like a popular solution, and it should fit inside your budget more or less. There is already software available (from John Miles for instance) that works with that solution, but it should also allow yourself some programming exercises. This will certainly get you started. There are several decades to go down into the noise for the really good sources and reducing measurement noise. It will be a fairly good solution for many decent sources. Grab a copy of the NIST SP 1065 and ponder over it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] IRIG-B with Arduino
In fact, I was looking very hard at the 328P. AND I just happen to have an STK500 on the way from the east coast (thanks to an Ebay purchase). Already got AVR Studio installed, and I also have IAR's AVR package standing by. In short, I've got plenty to learn with. And you're right. I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming rather than just taking abstract example problems. Banzai! ;-) *** REPLY SEPARATOR *** On 14-Dec-10 at 22:37 John Miles wrote: Fellow clock-tickers, I'm finally starting to learn microcontrollers, and have selected Atmel's AVR line as my tool of choice. I've also discovered the Arduino site, and am starting to learn their IDE as well. My first goal will be an open-source/open-hardware IRIG-B decoder (takes IRIG-B 1kHz stream, sends the timecode to an LCD panel). I've noticed a distinct lack of hobby-priced decoders on the market, and I intend to try and remedy that. My initial development platform will be the Arduino Mega-2560 board. However, that particular microcontroller is unlikely to be my final chip of choice due to the fact it's not available in a hobbyist-friendly DIP package. If others with more development skill have suggestions for a different chip, I will gladly listen. Stay tuned for further developments (no pun intended). I expect this to take at least a few months, as the learning curve looks kind of steep. That's a good family of parts to start out with. It is very well supported and easy to work with. You don't really need to mess with the Arduino IDE and all the trimmings -- just set up AVR-GCC with WinAVR or one of the newer distributions and go from there. If you have ever done any C programming before, the learning curve will be measured in hours or days, not months. If you haven't, well... there's always assembly. There is a new low-cost kit with Arduino-like USB programming capability on the market: http://www.seeedstudio.com/depot/usnoobie-kit-p-708.html?cPath=104_128 The first batch of these shipped with broken bootloader code so you have to have an STK-500 or similar programmer to get them up and running. I imagine that's been fixed by now, but at any rate, the Atmega328P is probably the chip you want, if you want a higher-end AVR controller that still comes in a DIP. I just rigged one of them up to drive a YIG synthesizer: http://www.thegleam.com/ke5fx/stellex.htm (see December 2010 update at the very bottom of the page). Apart from the USB bootloader confusion and the presence of a couple of spurious error/warning messages in the avrdude.exe programmer utility, I'd give it two thumbs up at a minimum. Great little device. -- john, KE5FX ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] IRIG-B with Arduino
That's the thing. I don't want to have to rely on PC hardware. I really want to make something which is stand-alone, and can be wired to a variety of displays. Keep the peace(es). *** REPLY SEPARATOR *** On 14-Dec-10 at 22:59 Chris Albertson wrote: If the goal is to learn about AVRs that is a good project. But if you want a cheap IRIG decoder I bet you already have one. An IRIG driver is included with NTP. The NTP driver reads the time code from an audio interface set for 8Khz sample rate.If you are writing a decoder it might be good to study the NTP source code. They do good bit of error checking and averaging and get to microsecond level even on noisy signals. But then it runs on an full size 32 or 64 bit computer There is also an irig time code generator in the source .tar file but it is not compiled by the Makefile, yu have to do that by hand. No the IRIG driver is compiled by default On Tue, Dec 14, 2010 at 10:19 PM, Bruce Lane kyr...@bluefeathertech.com wrote: Fellow clock-tickers, I'm finally starting to learn microcontrollers, and have selected Atmel's AVR line as my tool of choice. I've also discovered the Arduino site, and am starting to learn their IDE as well. My first goal will be an open-source/open-hardware IRIG-B decoder (takes IRIG-B 1kHz stream, sends the timecode to an LCD panel). I've noticed a distinct lack of hobby-priced decoders on the market, and I intend to try and remedy that. My initial development platform will be the Arduino Mega-2560 board. However, that particular microcontroller is unlikely to be my final chip of choice due to the fact it's not available in a hobbyist-friendly DIP package. If others with more development skill have suggestions for a different chip, I will gladly listen. Stay tuned for further developments (no pun intended). I expect this to take at least a few months, as the learning curve looks kind of steep. -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] IRIG-B with Arduino
Already a bit ahead of you, Don. The Mega just happened to be the one I started with. I selected it because I found details online for someone who used the Mega to construct a clock which runs from decoding NMEA sentences, and I'm using his source code to help me along. Keep the peace(es). *** REPLY SEPARATOR *** On 14-Dec-10 at 23:59 Don Latham wrote: Bruce: You may not need the Mega. I started with the arduino in duemilanuove, and found that there are chips with the bootloader available. The IDE is actually pretty good, not too steep, and there are libraries available for lots of peripherals and lots of sample code. I suggest Sparkfun as a source, I have had very satisfactory dealings with them. The Due also has piggyback boards called, for some unknown reason shields, which make the construction of small systems very easy. Don - Original Message - From: Bruce Lane kyr...@bluefeathertech.com To: time-nuts@febo.com Sent: Tuesday, December 14, 2010 11:19 PM Subject: [time-nuts] IRIG-B with Arduino Fellow clock-tickers, I'm finally starting to learn microcontrollers, and have selected Atmel's AVR line as my tool of choice. I've also discovered the Arduino site, and am starting to learn their IDE as well. My first goal will be an open-source/open-hardware IRIG-B decoder (takes IRIG-B 1kHz stream, sends the timecode to an LCD panel). I've noticed a distinct lack of hobby-priced decoders on the market, and I intend to try and remedy that. My initial development platform will be the Arduino Mega-2560 board. However, that particular microcontroller is unlikely to be my final chip of choice due to the fact it's not available in a hobbyist-friendly DIP package. If others with more development skill have suggestions for a different chip, I will gladly listen. Stay tuned for further developments (no pun intended). I expect this to take at least a few months, as the learning curve looks kind of steep. -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] IRIG-B with Arduino
You may want to avoid the 328p. for the last year there have been supply problems to the distributors. -eric Sent from my Banana jr (tm) Mobile Device On Dec 15, 2010, at 6:23 PM, Bruce Lane kyr...@bluefeathertech.com wrote: In fact, I was looking very hard at the 328P. AND I just happen to have an STK500 on the way from the east coast (thanks to an Ebay purchase). Already got AVR Studio installed, and I also have IAR's AVR package standing by. In short, I've got plenty to learn with. And you're right. I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming rather than just taking abstract example problems. Banzai! ;-) *** REPLY SEPARATOR *** On 14-Dec-10 at 22:37 John Miles wrote: Fellow clock-tickers, I'm finally starting to learn microcontrollers, and have selected Atmel's AVR line as my tool of choice. I've also discovered the Arduino site, and am starting to learn their IDE as well. My first goal will be an open-source/open-hardware IRIG-B decoder (takes IRIG-B 1kHz stream, sends the timecode to an LCD panel). I've noticed a distinct lack of hobby-priced decoders on the market, and I intend to try and remedy that. My initial development platform will be the Arduino Mega-2560 board. However, that particular microcontroller is unlikely to be my final chip of choice due to the fact it's not available in a hobbyist-friendly DIP package. If others with more development skill have suggestions for a different chip, I will gladly listen. Stay tuned for further developments (no pun intended). I expect this to take at least a few months, as the learning curve looks kind of steep. That's a good family of parts to start out with. It is very well supported and easy to work with. You don't really need to mess with the Arduino IDE and all the trimmings -- just set up AVR-GCC with WinAVR or one of the newer distributions and go from there. If you have ever done any C programming before, the learning curve will be measured in hours or days, not months. If you haven't, well... there's always assembly. There is a new low-cost kit with Arduino-like USB programming capability on the market: http://www.seeedstudio.com/depot/usnoobie-kit-p-708.html?cPath=104_128 The first batch of these shipped with broken bootloader code so you have to have an STK-500 or similar programmer to get them up and running. I imagine that's been fixed by now, but at any rate, the Atmega328P is probably the chip you want, if you want a higher-end AVR controller that still comes in a DIP. I just rigged one of them up to drive a YIG synthesizer: http://www.thegleam.com/ke5fx/stellex.htm (see December 2010 update at the very bottom of the page). Apart from the USB bootloader confusion and the presence of a couple of spurious error/warning messages in the avrdude.exe programmer utility, I'd give it two thumbs up at a minimum. Great little device. -- john, KE5FX ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] IRIG-B with Arduino
Hmm! Hadn't heard that... Any other Atmel DIPs among the AVR family you'd suggest? Thanks. *** REPLY SEPARATOR *** On 15-Dec-10 at 18:44 Eric Garner wrote: You may want to avoid the 328p. for the last year there have been supply problems to the distributors. -eric Sent from my Banana jr (tm) Mobile Device On Dec 15, 2010, at 6:23 PM, Bruce Lane kyr...@bluefeathertech.com wrote: In fact, I was looking very hard at the 328P. AND I just happen to have an STK500 on the way from the east coast (thanks to an Ebay purchase). Already got AVR Studio installed, and I also have IAR's AVR package standing by. In short, I've got plenty to learn with. And you're right. I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming rather than just taking abstract example problems. Banzai! ;-) *** REPLY SEPARATOR *** On 14-Dec-10 at 22:37 John Miles wrote: Fellow clock-tickers, I'm finally starting to learn microcontrollers, and have selected Atmel's AVR line as my tool of choice. I've also discovered the Arduino site, and am starting to learn their IDE as well. My first goal will be an open-source/open-hardware IRIG-B decoder (takes IRIG-B 1kHz stream, sends the timecode to an LCD panel). I've noticed a distinct lack of hobby-priced decoders on the market, and I intend to try and remedy that. My initial development platform will be the Arduino Mega-2560 board. However, that particular microcontroller is unlikely to be my final chip of choice due to the fact it's not available in a hobbyist-friendly DIP package. If others with more development skill have suggestions for a different chip, I will gladly listen. Stay tuned for further developments (no pun intended). I expect this to take at least a few months, as the learning curve looks kind of steep. That's a good family of parts to start out with. It is very well supported and easy to work with. You don't really need to mess with the Arduino IDE and all the trimmings -- just set up AVR-GCC with WinAVR or one of the newer distributions and go from there. If you have ever done any C programming before, the learning curve will be measured in hours or days, not months. If you haven't, well... there's always assembly. There is a new low-cost kit with Arduino-like USB programming capability on the market: http://www.seeedstudio.com/depot/usnoobie-kit-p-708.html?cPath=104_128 The first batch of these shipped with broken bootloader code so you have to have an STK-500 or similar programmer to get them up and running. I imagine that's been fixed by now, but at any rate, the Atmega328P is probably the chip you want, if you want a higher-end AVR controller that still comes in a DIP. I just rigged one of them up to drive a YIG synthesizer: http://www.thegleam.com/ke5fx/stellex.htm (see December 2010 update at the very bottom of the page). Apart from the USB bootloader confusion and the presence of a couple of spurious error/warning messages in the avrdude.exe programmer utility, I'd give it two thumbs up at a minimum. Great little device. -- john, KE5FX ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] IRIG-B with Arduino
On Wed, Dec 15, 2010 at 6:23 PM, Bruce Lane kyr...@bluefeathertech.com wrote: . I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming ... I agree with the last part. Learn by doing some real project. But no the first part. The best platform for learning is a full size computer with a real OS on it. Programming a micro-controller s MUCH harder than programming a LInux desktop machine. I've done both, pretty much full time now for 30 years. In fact if I want to get something to run on an AVR in C I will write and mostly debug the code as much as I can on the big Linux computer. The there are some simulators too. Of course you have to move to the target hardware as some point but it is always best if you plan the project so that you can delay that time. That is one of the major advantages of the AVR over PIC, the AVR works well with C so you can to more of the work on the bigger computer. Getting back to the time code project. Do look at the generator in NTP. Run it on the desktop and study the code -- = 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] IRIG-B with Arduino
I must not have made myself clear. I certainly plan to use the development environments on my PC. That is, after all, why I loaded up AVR Studio and the IAR packages. Can you provide a link for the NTP thing you mention? Thanks. *** REPLY SEPARATOR *** On 15-Dec-10 at 20:27 Chris Albertson wrote: On Wed, Dec 15, 2010 at 6:23 PM, Bruce Lane kyr...@bluefeathertech.com wrote: . I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming ... I agree with the last part. Learn by doing some real project. But no the first part. The best platform for learning is a full size computer with a real OS on it. Programming a micro-controller s MUCH harder than programming a LInux desktop machine. I've done both, pretty much full time now for 30 years. In fact if I want to get something to run on an AVR in C I will write and mostly debug the code as much as I can on the big Linux computer. The there are some simulators too. Of course you have to move to the target hardware as some point but it is always best if you plan the project so that you can delay that time. That is one of the major advantages of the AVR over PIC, the AVR works well with C so you can to more of the work on the bigger computer. Getting back to the time code project. Do look at the generator in NTP. Run it on the desktop and study the code -- = 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] IRIG-B with Arduino
The 168 is it's junior cousin, and it's available. Sent from my Banana jr (tm) Mobile Device On Dec 15, 2010, at 7:21 PM, Bruce Lane kyr...@bluefeathertech.com wrote: Hmm! Hadn't heard that... Any other Atmel DIPs among the AVR family you'd suggest? Thanks. *** REPLY SEPARATOR *** On 15-Dec-10 at 18:44 Eric Garner wrote: You may want to avoid the 328p. for the last year there have been supply problems to the distributors. -eric Sent from my Banana jr (tm) Mobile Device On Dec 15, 2010, at 6:23 PM, Bruce Lane kyr...@bluefeathertech.com wrote: In fact, I was looking very hard at the 328P. AND I just happen to have an STK500 on the way from the east coast (thanks to an Ebay purchase). Already got AVR Studio installed, and I also have IAR's AVR package standing by. In short, I've got plenty to learn with. And you're right. I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming rather than just taking abstract example problems. Banzai! ;-) *** REPLY SEPARATOR *** On 14-Dec-10 at 22:37 John Miles wrote: Fellow clock-tickers, I'm finally starting to learn microcontrollers, and have selected Atmel's AVR line as my tool of choice. I've also discovered the Arduino site, and am starting to learn their IDE as well. My first goal will be an open-source/open-hardware IRIG-B decoder (takes IRIG-B 1kHz stream, sends the timecode to an LCD panel). I've noticed a distinct lack of hobby-priced decoders on the market, and I intend to try and remedy that. My initial development platform will be the Arduino Mega-2560 board. However, that particular microcontroller is unlikely to be my final chip of choice due to the fact it's not available in a hobbyist-friendly DIP package. If others with more development skill have suggestions for a different chip, I will gladly listen. Stay tuned for further developments (no pun intended). I expect this to take at least a few months, as the learning curve looks kind of steep. That's a good family of parts to start out with. It is very well supported and easy to work with. You don't really need to mess with the Arduino IDE and all the trimmings -- just set up AVR-GCC with WinAVR or one of the newer distributions and go from there. If you have ever done any C programming before, the learning curve will be measured in hours or days, not months. If you haven't, well... there's always assembly. There is a new low-cost kit with Arduino-like USB programming capability on the market: http://www.seeedstudio.com/depot/usnoobie-kit-p-708.html?cPath=104_128 The first batch of these shipped with broken bootloader code so you have to have an STK-500 or similar programmer to get them up and running. I imagine that's been fixed by now, but at any rate, the Atmega328P is probably the chip you want, if you want a higher-end AVR controller that still comes in a DIP. I just rigged one of them up to drive a YIG synthesizer: http://www.thegleam.com/ke5fx/stellex.htm (see December 2010 update at the very bottom of the page). Apart from the USB bootloader confusion and the presence of a couple of spurious error/warning messages in the avrdude.exe programmer utility, I'd give it two thumbs up at a minimum. Great little device. -- john, KE5FX ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go
Re: [time-nuts] TAC/TDC
Magnus Danielson wrote: On 12/15/2010 08:13 AM, Josef Kölbl wrote: Magnus, with regard to your questions: measurement rate = 1 kHz rms jitter = 10 ps linearity better 3 ps resolution of 1 ps is the minimum differential measurement which can be made (ie granularity). Thanks, this makes your requirements much clearer. This does not seem to be within reach of the ACAM devices and the PICTIC II is not in that neightborhood either: http://www.thegleam.com/ke5fx/pictic.htm Considering the 25 ns maximum TI difference (if I recall your specs correctly) it would require a 16 bit ADC besides good input. I doubt that you would find a complete solution lying around, but either you revamp the PICTIC II concept or go for some other variant of time interpolation. Maybe Bruce may give some suitable advice. Cheers, Magnus The resolution and noise requirements can be met using a TAC. The Wavecrest 2075, for example, uses a TAC plus a high resolution ADC to achieve sub ps resolution coupled with a noise of a few ps rms. A 16bit ADC will suffice for 1ps resolution over a 25ns range. The trick in achieving the required TAC performance will require adoption of similar techniques to those used in the Wavecrest 2075 as detailed in the associated patent. Most of the details within the patent were well known decades before the time the patent was issued. The Waverest 2075 makes extensive use of ECL together with discrete CML switches. A good PCB layout preferably using a 4 layer board or equivalent will probably be required. A ringing LC style TDC should also easily achieve the desired noise and resolution if the results (by an italian group) using a crude switch (its relatively easy to devise a switch with much higher performance) to excite an LC circuit are anything to go by. However a pipeline or similar ADC sampling the resultant decaying sinusoid at 80MSPS or more are required together with an FPGA (or DSP) to process the ADC samples. The LC circuit should resonate at around 5-10MHz or so. The exact frequency isnt critical as long as its relatively stable in the short term as the ringing frequency can be one of the parameters fitted to sample burst of the exponentially decaying sinewave. Simulations indicate that repetition rates of 10KHz or more should be readily achievable. 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] IRIG-B with Arduino
Loks like I need to make myself clear also. Sorry. When I said develop on the desktop I meant for a desktop target. Writing code this is to run on the desktop is far easier then wrioting code that is to run in a micro controller. Of course in both cases to type and edit using ther desktop machine. I have programmed micros using toggle switches and push buttons to directly load in binary code bit by bit put that gets old real quick but that was the way it was done. So to be redundant. The best way to learn programming in C is to do so by writing for a simple and easy to use target execution environment. The simplest is a command line terminal You can find the source code for NTP at http://www.ntp.org/downloads.html un tar the file into somedir and then look at ...somedir/ntp-4.2.6p2/ntp/refclock_irig.b and in there is the code to read IRIG and also some good comments that explain both irig and how to decode it. This code samples the irig signal 8,000 times per second and does the demodulation in software. It also does to ntp stuff that you don't need to care about The other file is in the utils directory and is a time code generator used mostly for testing decoders On Wed, Dec 15, 2010 at 8:46 PM, Bruce Lane kyr...@bluefeathertech.com wrote: I must not have made myself clear. I certainly plan to use the development environments on my PC. That is, after all, why I loaded up AVR Studio and the IAR packages. Can you provide a link for the NTP thing you mention? Thanks. *** REPLY SEPARATOR *** On 15-Dec-10 at 20:27 Chris Albertson wrote: On Wed, Dec 15, 2010 at 6:23 PM, Bruce Lane kyr...@bluefeathertech.com wrote: . I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming ... I agree with the last part. Learn by doing some real project. But no the first part. The best platform for learning is a full size computer with a real OS on it. Programming a micro-controller s MUCH harder than programming a LInux desktop machine. I've done both, pretty much full time now for 30 years. In fact if I want to get something to run on an AVR in C I will write and mostly debug the code as much as I can on the big Linux computer. The there are some simulators too. Of course you have to move to the target hardware as some point but it is always best if you plan the project so that you can delay that time. That is one of the major advantages of the AVR over PIC, the AVR works well with C so you can to more of the work on the bigger computer. Getting back to the time code project. Do look at the generator in NTP. Run it on the desktop and study the code -- = 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] Frequency counter recommendation
I've seen several posts that mention the 5370 counter. Certainly looks like a capable instrument. I'll be on the lookout for one that is in reasonably good condition and WORKS. I downloaded the NIST pub that you mentioned, and with the cold days and colder nights, I'll have lots of time to ponder it. Re: Don Latham's response - I've never seen Robot BASIC, but I'll look it up. I assume that it's a GPIB controller application?? Re Stan, W1LE's response - Thanks for the Prologix recommendation. I'll look into it. And thanks to all the other responders... I really appreciate your taking time to offer your advice. Dave M Hi Dave, On 12/15/2010 08:55 PM, Dave M wrote: I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. A HP5370A/B and a Prologix USB-GPIB interface seems like a popular solution, and it should fit inside your budget more or less. There is already software available (from John Miles for instance) that works with that solution, but it should also allow yourself some programming exercises. This will certainly get you started. There are several decades to go down into the noise for the really good sources and reducing measurement noise. It will be a fairly good solution for many decent sources. Grab a copy of the NIST SP 1065 and ponder over it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] IRIG-B with Arduino
Thanks, Chris. Between that and what I've found already, I think this is very do-able. Keep the peace(es). *** REPLY SEPARATOR *** On 15-Dec-10 at 21:52 Chris Albertson wrote: Loks like I need to make myself clear also. Sorry. When I said develop on the desktop I meant for a desktop target. Writing code this is to run on the desktop is far easier then wrioting code that is to run in a micro controller. Of course in both cases to type and edit using ther desktop machine. I have programmed micros using toggle switches and push buttons to directly load in binary code bit by bit put that gets old real quick but that was the way it was done. So to be redundant. The best way to learn programming in C is to do so by writing for a simple and easy to use target execution environment. The simplest is a command line terminal You can find the source code for NTP at http://www.ntp.org/downloads.html un tar the file into somedir and then look at ...somedir/ntp-4.2.6p2/ntp/refclock_irig.b and in there is the code to read IRIG and also some good comments that explain both irig and how to decode it. This code samples the irig signal 8,000 times per second and does the demodulation in software. It also does to ntp stuff that you don't need to care about The other file is in the utils directory and is a time code generator used mostly for testing decoders On Wed, Dec 15, 2010 at 8:46 PM, Bruce Lane kyr...@bluefeathertech.com wrote: I must not have made myself clear. I certainly plan to use the development environments on my PC. That is, after all, why I loaded up AVR Studio and the IAR packages. Can you provide a link for the NTP thing you mention? Thanks. *** REPLY SEPARATOR *** On 15-Dec-10 at 20:27 Chris Albertson wrote: On Wed, Dec 15, 2010 at 6:23 PM, Bruce Lane kyr...@bluefeathertech.com wrote: . I'll be learning both C and AVR assembler as I go along, but the way I learn best is to actually DO something with programming ... I agree with the last part. Learn by doing some real project. But no the first part. The best platform for learning is a full size computer with a real OS on it. Programming a micro-controller s MUCH harder than programming a LInux desktop machine. I've done both, pretty much full time now for 30 years. In fact if I want to get something to run on an AVR in C I will write and mostly debug the code as much as I can on the big Linux computer. The there are some simulators too. Of course you have to move to the target hardware as some point but it is always best if you plan the project so that you can delay that time. That is one of the major advantages of the AVR over PIC, the AVR works well with C so you can to more of the work on the bigger computer. Getting back to the time code project. Do look at the generator in NTP. Run it on the desktop and study the code -- = 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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. __ Information from ESET NOD32 Antivirus, version of virus signature database 5706 (20101215) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com -=-=-=-=-=-=-=-=-=-=-=- Bruce Lane, Owner Head Hardware Heavy, Blue Feather Technologies -- http://www.bluefeathertech.com kyrrin (at) bluefeathertech do/t c=o=m Quid Malmborg in Plano... ___ 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] Frequency counter recommendation
I asked the same question of this list a number of years back, took a few different routes and ended up with precisely what has been suggested here: HP 5370B Prologix GPIB-USB And an HP 3325B function generator to round it all out nicely. Also, if ever asked by the financial controller *why* you bought such a 5370B, a cool demo is to demonstrate the speed of electricity along a metre or two of cable. Jim Palfreyman On 16 December 2010 16:54, Dave M dgmin...@mediacombb.net wrote: I've seen several posts that mention the 5370 counter. Certainly looks like a capable instrument. I'll be on the lookout for one that is in reasonably good condition and WORKS. I downloaded the NIST pub that you mentioned, and with the cold days and colder nights, I'll have lots of time to ponder it. Re: Don Latham's response - I've never seen Robot BASIC, but I'll look it up. I assume that it's a GPIB controller application?? Re Stan, W1LE's response - Thanks for the Prologix recommendation. I'll look into it. And thanks to all the other responders... I really appreciate your taking time to offer your advice. Dave M Hi Dave, On 12/15/2010 08:55 PM, Dave M wrote: I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. A HP5370A/B and a Prologix USB-GPIB interface seems like a popular solution, and it should fit inside your budget more or less. There is already software available (from John Miles for instance) that works with that solution, but it should also allow yourself some programming exercises. This will certainly get you started. There are several decades to go down into the noise for the really good sources and reducing measurement noise. It will be a fairly good solution for many decent sources. Grab a copy of the NIST SP 1065 and ponder over it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Frequency counter recommendation
Dave: the Prologix interface can be used as an rs232 device. In that way, a robot basic program can be written to control GPIB devices. I like Robot Basic because it is has no connections to .net or any of the other microsoft stuff, AFIK uses no Registry either.. I put the whole package in a folder on my desktop and run it from there. Neat and tidy and completely portable. In fact, the whole thing can run from a USB card. Also makes .exe's. I finally got motivated to buy a Prologix interface, got tired of fighting with the very old Measurement and Computing card, it's just too old and weird to use. I bought the network adapter instead of the USB, so any computer on my little local network can be used. This is a new adventure... Good luck with your project. Don Dave M I've seen several posts that mention the 5370 counter. Certainly looks like a capable instrument. I'll be on the lookout for one that is in reasonably good condition and WORKS. I downloaded the NIST pub that you mentioned, and with the cold days and colder nights, I'll have lots of time to ponder it. Re: Don Latham's response - I've never seen Robot BASIC, but I'll look it up. I assume that it's a GPIB controller application?? Re Stan, W1LE's response - Thanks for the Prologix recommendation. I'll look into it. And thanks to all the other responders... I really appreciate your taking time to offer your advice. Dave M Hi Dave, On 12/15/2010 08:55 PM, Dave M wrote: I'm a retired electronics tech and computer programmer. I have a pretty decently equipped shop for almost all of my projects and experiments. However, my time and frequency equipment is a bit long in the tooth. I have a couple old HP 5328A counters (commercial version; not the military version), one with a 10544, the other with a 10811 oscillator. I have an HP Z3801A that has been operating well for several years, and recently acquired a TBolt to keep the counters in tune. I also have a good distribution amp and couple of old Montronics (Fluke) frequency comparators. What I'm looking for now, is a recommendation for a good low-cost ($400) counter that will get me on the way to performing some of the down in the grass noise, jitter and deviation tests that the more learned members of the group discuss. I know that new equipment is far out of my budget, but I'm also aware that some of the older, now obsolete (also cheaper) equipment is quite capable of doing what I want to do. I prefer HP equipment since manuals are much easier to find than most other brands. I'd also like recommendation for a good low-cost GPIB controller that allows me to write software to control some of my instruments. I have experience writing software in BASIC on a Fluke 1722A controller. I've seen these controllers on the Bay and other online vendors, but I've not located the BASIC discs for them. Any advice? I realize that a counter is not the only piece that I need, but it's first on my list. Other, more applicable equipment is on my want list, but will have to wait for a bit. A HP5370A/B and a Prologix USB-GPIB interface seems like a popular solution, and it should fit inside your budget more or less. There is already software available (from John Miles for instance) that works with that solution, but it should also allow yourself some programming exercises. This will certainly get you started. There are several decades to go down into the noise for the really good sources and reducing measurement noise. It will be a fairly good solution for many decent sources. Grab a copy of the NIST SP 1065 and ponder over it. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- 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.
