Re: [time-nuts] GPS timing antenna 5 meter BNC Plug with cable
Amazing how reasonable some of these Chinese cables and other electronics are. The quality is also constantly improving. But I would see if they can use at least RG/142. It is more expensive but I would not recommend RG/58 for a GPS antenna. Or even for distributing 5 and 10 MHz outputs if you are going for maximum performance. At 40GHz bandwidth the 2.4mm connectors require precision machining. In addition the cable will need to act as a waveguide beyond about 30Ghz. Needless to say they will always command some serious money. If you are going to that expense I would recommend 2.4mm to 2.4mm with a 2.4mm to 3.5mm adpater. An SMA connector will limit the cable to use below 20GHz. Skip at RDR has had some new surplus 2.4mm cables recently. He may still have some longer lengths. They are not $6, but they were reasonably priced and very nice. Thomas Knox Date: Thu, 5 Dec 2013 16:31:13 + From: drkir...@gmail.com To: time-nuts@febo.com Subject: Re: [time-nuts] GPS timing antenna 5 meter BNC Plug with cable On 5 December 2013 05:56, David J Taylor david-tay...@blueyonder.co.uk wrote: Anyone know whether these antennas are any good? Anyone used one? I wonder where they are made? http://www.rfsupplier.com/timing-antenna-meter-plug-with-rg58-coax-cable-p-2344.html Looks like it has no filter, and some of the spelling is dubious! Thanks, David Reading the site Rfsupplier is a online b2c company located in Shenzhen, China which specialized... I agree the English is odd, but it is better than my Chinese. Its an interesting site that will make cables of arbitrary length with arbitrary connectors, though I think they might struggle to make this cable they quote $6 for. Product: Cable Type: RG8; Length: 0.1cm/0.04inch(s); Connector A: N Straight Jack; Connector B: N Right Angle Plug I wish I could find a similar site that would make me a cable with a 2.4 mm male plug at one end, and a female chassis mount SMA on the other. I suspect a company like Huber and Suhner could make me one, but I suspect it would be a small fortune for a one-off. Dave ___ time-nuts mailing 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] ***SPAM*** Serial cables with thin connectors
HI I’ve ran into this on 1U multi port adapters. The only solution I found was to get one each from a number of suppliers. Once I found one that fit, I ordered more. Two months later when I bought another batch of the same part number they were a different size. Bob On Dec 5, 2013, at 6:10 PM, Hal Murray hmur...@megapathdsl.net wrote: I'm trying to update PCs to save power. The Intel D2500CCE mini-ITX board is attractive because it has a second serial port on the back panel. It uses stacked DB-9 connectors. The catch is they are only 0.625 inches apart. All of the molded connectors on the serial cables in my collection are slightly thicker than that. Does anybody have a good source of serial cables with connectors that will fit? This must be a solved problem by now, but my google-fu hasn't worked. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Fwd: [Moon-Net] [Moon] 10GHz EME beacon?
I thought this might interest some - a beacon at 1296 MHz GPS locked in frequency and time of sending, and directed at the moon. Apparently it has been heard with a 1.5 m dish. Someone is planning doing similar at 10 GHz. Dave -- Forwarded message -- From: Eddy Jespers ejesp...@telenet.be Date: 5 December 2013 20:57 Subject: Re: [Moon-Net] [Moon] 10GHz EME beacon? To: DL6LAU dl6...@appello.de, m...@moonbounce.info, moon-...@mailman.pe1itr.com Hi Carsten, Indeed a good idea. In regards of frequency, we chose at the 1296 ON0EME EME beacon to use the start frequency of the EME band, being 1296.000 MHz, reference locked to GPS to have a frequency standard on the band. People can use the beacon to verify the frequency accuracy of their systems. I believe the start freq. on 3cm is 10368.100 , correct me when I'm wrong. We also chose to start the beacon message at exact 00 seconds of the minute, also GPS driven. This gives the beacon also a timing standard, distance to the moon can be checked and verified. We did have a license restriction we could not start transmitting at 0° elevation with half a megawatt of EIRP, since the antenna is only 6 meters above ground. You may consider talking to Walter ON4BCB who was responsible for the autotracking and the keying of ON0EME, he made the complete interface based on Hannes OE5JFL's design. More info here on the making of ON0EME : http://users.skynet.be/on0eme/ON0EME/Welcome.html Success with the project ! Vy 73's Eddy ON7UN -Oorspronkelijk bericht- Van: moon-boun...@moonbounce.info [mailto:moon-boun...@moonbounce.info] Namens DL6LAU Verzonden: donderdag 5 december 2013 17:59 Aan: m...@moonbounce.info; moon-...@mailman.pe1itr.com Onderwerp: [Moon] 10GHz EME beacon? Hi guys, we at DL0SHF are discussing, if a 10GHz EME beacon would be of benefit (to someone) ... Seems we could easily have our 7.6m dish with 50W SSPA running towards the moon, when visible in JO54 ... (unless we use the station ourself for QSOs). Would this be interesting? Any suggestion for a frequency? 73ss Carsten, DL6LAU (OP @ DL0SHF) ___ Moon mailing list m...@moonbounce.info http://lists.moonbounce.info/cgi-bin/mailman/listinfo/moon - Geen virus gevonden in dit bericht. Gecontroleerd door AVG - www.avg.com Versie: 2014.0.4259 / Virusdatabase: 3658/6893 - datum van uitgifte: 12/05/13 - Geen virus gevonden in dit bericht. Gecontroleerd door AVG - www.avg.com Versie: 2014.0.4259 / Virusdatabase: 3629/6876 - datum van uitgifte: 11/28/13 ___ Moon-Net posting and subscription instructions are at http://www.nlsa.com/nets/moon-net-help.html -- Dr. David Kirkby G8WRB http://www.vnacalibration.co.uk/ Economical accurate VNA calibration kits. Coefficients available for HP, Agilent, Anritsu, Rohde Schwarz and VNWA network analyzers. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS timing antenna 5 meter BNC Plug with cable
I've used them quite a bit and they will do custom stuff at very reasonable prices. Kiki's details are : ShenZhen Superbat Electronics Co.,Ltd www.rfstreet.com pay...@rfstreet.com lucyzhangyi...@live.cn rfsupplier Mob:+86 13923809471 /Tel :+86 755 25614980 I love the way she wishes me good luck with all my orders, Not sure luck is something I want with my orders :) Anthony On Thu, Dec 5, 2013 at 4:17 PM, Rob Kimberley robkimber...@btinternet.comwrote: Chinese email address on web site. Rob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of David J Taylor Sent: 05 December 2013 05:56 To: Time-nuts mailing list Subject: [time-nuts] GPS timing antenna 5 meter BNC Plug with cable Anyone know whether these antennas are any good? Anyone used one? I wonder where they are made? http://www.rfsupplier.com/timing-antenna-meter-plug-with-rg58-coax-cable-p-2 344.html Looks like it has no filter, and some of the spelling is dubious! Thanks, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] Efratom Rubidium SPTB-100/LN-001 info wanted
Thanks Rex, this is terrific information! It is awfully kind of you to take the time effort to write up and post the note. I'm all set now. The generosity of the Time-nuts community if very inspiring. Jerome AF6UX -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Rex Sent: Thursday, December 05, 2013 4:35 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Efratom Rubidium SPTB-100/LN-001 info wanted I have an SPTB-100. It seems to be a custom version of a standard FRK(LN) rubidium for Tektronics. I got mine around 2000. (Mine is an 88 date-code vs. your ancient 86 version.) It didn't work initially because the internal Xtal oscillator wouldn't sweep through lock frequency. Changed a cap in the oscillator and it worked again. I've only powered it up a few times; I assume mine is still working. I was told it is low-noise for a rubidium. Somewhere locally, I got a copy of a manual for it. Other than the cover page, it seems to be a standard FRK manual, which the KO4BB pages already have. Today, I made a short PDF with a scan of the cover page and a few notes I wrote up. You can get it here: http://www.xertech.net/pub/SPTB-100%20notes.pdf I also uploaded it to KO4BB for future references. If anyone knows more or sees any problems with what I wrote up, please let me know and I'll correct or update. -Rex KK6MK On 12/4/2013 7:08 PM, Jerome Peters wrote: Hello, Can anybody shed some light on this particular model: Model - SPTB-100/LN-001 Efratom part No. 703-200-11 Date Code 8609 (I have looked at K04BB's website, it has lots of other models, but not this one). Thank You, Jerome AF6UX -- - This email message is for the sole use of the intended recipient(s) and may contain confidential information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message. -- - ___ time-nuts mailing 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] Serial cables with thin connectors
On Thu, Dec 5, 2013 at 6:10 PM, Hal Murray hmur...@megapathdsl.net wrote: The catch is they are only 0.625 inches apart. All of the molded connectors on the serial cables in my collection are slightly thicker than that. I've resolved this using (strain relieved) connectors without shells. You do have to have students make them up though. Unless you don't have students. For a small number crimp-on is not an ordeal (showing my no-solder bias). ___ time-nuts mailing 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] ***SPAM*** Serial cables with thin connectors
On Thu, Dec 5, 2013 at 5:10 PM, Hal Murray hmur...@megapathdsl.net wrote: I'm trying to update PCs to save power. The Intel D2500CCE mini-ITX board is attractive because it has a second serial port on the back panel. It uses stacked DB-9 connectors. The catch is they are only 0.625 inches apart. All of the molded connectors on the serial cables in my collection are slightly thicker than that. Does anybody have a good source of serial cables with connectors that will fit? This must be a solved problem by now, but my google-fu hasn't worked. My solution? A die grinder. I just hog-off the extra plastic until they fit. Of course, there is always the option of making your own using ribbon cable, or making a little extension with ribbon cable between a DB9-m and DB9-f. Never underestimate the power of brute-force and stupidity. -- Brian Lloyd, WB6RQN/J79BPL 706 Flightline Drive Spring Branch, TX 78070 br...@lloyd.com +1.916.877.5067 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS timing antenna 5 meter BNC Plug with cable
On 6 December 2013 07:52, Tom Knox act...@hotmail.com wrote: Amazing how reasonable some of these Chinese cables and other electronics are. The quality is also constantly improving. Though a lot is still poor. I got some adapters recently, and they are basically only fit for the bin. At 40GHz bandwidth the 2.4mm connectors require precision machining. In addition the cable will need to act as a waveguide beyond about 30Ghz. Needless to say they will always command some serious money. If you are going to that expense I would recommend 2.4mm to 2.4mm with a 2.4mm to 3.5mm adpater. An SMA connector will limit the cable to use below 20GHz. I want to work to 20 GHz only. It does need to be SMA, as I want to get direct receiver access on my VNA (8720D)., This was availalble from Agilent when the instrument was supported. It was option 012. It routed a few connections between internal parts of the VNA which are in 2.4 mm, and routes them to the front panel in SMA. In theory I could do it in 3.5 mm, but then the VNA would be non-standard and Agilent might refuse to calibrate it. There are 6 cables needed, along with a new front panel overlay. Agilent have them all except one cable. So I can't perform the upgrade. The use of the SMAs does cause a slight degraduation in one of the specs of the VNA, but the advantages would more than make up for that one thing. I'll give some thought to the 3.5 mm idea. In principle I could do it all in 2.4 mm in the VNA, have found 2.4 mm jumps on the front panel, and put an adapter when I need it. But if Agilent needed to disconnect those cables during calibration, they might refuse to calibrate it. Skip at RDR has had some new surplus 2.4mm cables recently. He may still have some longer lengths. Where is the web site for RDR - it is not a company I know of, and a Google did not find it. I only want 75-100 mm. Any longer would probably be a bad idea. They are not $6, but they were reasonably priced and very nice. I don't mind paying $7. No seriously, I know they wont be cheap. Agilent want $100-$300 for the other 2.4 mm to SMA cables, though they are pre-formed. I would need to bend a cable quite close to the SMA connector, which is a bit worrying, especially as I don't have a either a 2.4 or SMA connector gage - although I do have 3.5 mm gages. Dave Thomas Knox Date: Thu, 5 Dec 2013 16:31:13 + From: drkir...@gmail.com To: time-nuts@febo.com Subject: Re: [time-nuts] GPS timing antenna 5 meter BNC Plug with cable On 5 December 2013 05:56, David J Taylor david-tay...@blueyonder.co.uk wrote: Anyone know whether these antennas are any good? Anyone used one? I wonder where they are made? http://www.rfsupplier.com/timing-antenna-meter-plug-with-rg58-coax-cable-p-2344.html Looks like it has no filter, and some of the spelling is dubious! Thanks, David Reading the site Rfsupplier is a online b2c company located in Shenzhen, China which specialized... I agree the English is odd, but it is better than my Chinese. Its an interesting site that will make cables of arbitrary length with arbitrary connectors, though I think they might struggle to make this cable they quote $6 for. Product: Cable Type: RG8; Length: 0.1cm/0.04inch(s); Connector A: N Straight Jack; Connector B: N Right Angle Plug I wish I could find a similar site that would make me a cable with a 2.4 mm male plug at one end, and a female chassis mount SMA on the other. I suspect a company like Huber and Suhner could make me one, but I suspect it would be a small fortune for a one-off. Dave ___ time-nuts mailing 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. -- Dr. David Kirkby G8WRB http://www.vnacalibration.co.uk/ Economical accurate VNA calibration kits. Coefficients available for HP, Agilent, Anritsu, Rohde Schwarz and VNWA network analyzers. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] GPS timing antenna 5 meter BNC Plug with cable
On Fri, Dec 6, 2013 at 1:52 AM, Tom Knox act...@hotmail.com wrote: Amazing how reasonable some of these Chinese cables and other electronics are. The quality is also constantly improving. But I would see if they can use at least RG/142. It is more expensive but I would not recommend RG/58 for a GPS antenna. Or even for distributing 5 and 10 MHz outputs if you are going for maximum performance. I prefer RG-400 (teflon dielectric) myself but, yes, double shielded, silver plated braid RG-142 is good. At 40GHz bandwidth the 2.4mm connectors require precision machining. In addition the cable will need to act as a waveguide beyond about 30Ghz. Needless to say they will always command some serious money. If you are going to that expense I would recommend 2.4mm to 2.4mm with a 2.4mm to 3.5mm adpater. An SMA connector will limit the cable to use below 20GHz. Skip at RDR has had some new surplus 2.4mm cables recently. He may still have some longer lengths. They are not $6, but they were reasonably priced and very nice. I guess I'm a lo-fer then. I don't have anything that operates above 15GHz. The amazing thing is that I once thought that 1GHz was the next step below light. :-) -- Brian Lloyd, WB6RQN/J79BPL 706 Flightline Drive Spring Branch, TX 78070 br...@lloyd.com +1.916.877.5067 ___ time-nuts mailing 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] ***SPAM*** Serial cables with thin connectors
Can you find D2700s? It's been a while, but I thought the D2700s were better enough than the D2500s. Having said that, I also sometimes still use D525s, and pull the 2nd serial header out on a PCI slot header: http://www.supermicro.com/products/motherboard/ATOM/ICH9/X7SPA-HF-D525.cfm but I really like IPMI. These can be had for much less without IPMI. I'm also sometimes using S1260 Atoms: http://www.supermicro.com/products/motherboard/ATOM/X9/X9SBAA-F.cfm but these motherboards have very few USB ports. One of these days I'll get one of these that have an audio port and play with IRIG and stuff... H -- Harlan Stenn st...@ntp.org http://networktimefoundation.org - be a member! ___ time-nuts mailing 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] ***SPAM*** Serial cables with thin connectors
Ta On Thu, Dec 5, 2013 at 3:10 PM, Hal Murray hmur...@megapathdsl.net wrote: The catch is they are only 0.625 inches apart. All of the molded connectors on the serial cables in my collection are slightly thicker than that. I bought an Intel Atom board some time ago, try either of these ideas... - Ribbon cables with IDC type termination or, - Buy a bare DB9 connector and solder your own wires or - Find a cable with a removable shell. Something like this: http://www.jameco.com/1/1/28445-fc-9pm-9sm-6ft-r-6-foot-db9-male-female-flat-ribbon-cable.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] Using a UBlox NEO-6 GPS module for calibrating a PIC microprocessor based timer.
I want to thank everyone for the info! I'm still reading and trying to learn from it. I think I have another hobby starting. Monitoring the GPS performance looked like a good start. I have the serial port connected to a PC and have been monitoring it with the U-Center software available on the U-Blox site. So far, the minimum number of connected satellites is 5 and the maximum is 12. I also see a maximum position error of about 50 meters. Is this good enough or do I need a better signal? I don't have the receiver located in a very good spot. My workshop is in the basement. I have it next to a basement window. I have a view of less than half of the sky. I did check the configuration of the 1 PPS output. It's set to only output pulses when the data is valid. After monitoring it for a couple of days the 1 PPS signal has not dropped out. Also, I should say that I'm not planning on having my PIC timer permanently connected to a GPS. I just want to use it for testing and an occasional calibration check. Quartz55, Yes, you can use a PC with a sound card. There's even a program called Windows timing machine available that does this. I've tested it and had poor results. One computer worked better than the other. Neither worked very well. I think it's probably dependent on the quality of the sound card. I also wanted the convenience of a small portable timer instead of a PC. Tom Van Baak, I've looked at Brian Mumford's Microset timer. I think it's the best one available. If I hadn't decided to make my own I'd have bought his. I really don't need all of the features of his timer. It just came down to the fact that my spare time to write code is free and PIC chips only cost about a buck :-) I'm using a PIC 18F13K22. My code is in assembly language. The external clock is 10MHz. Internally it's running at 40MHz using the 4x PLL. The PIC 18 takes four clock cycles to execute one instruction cycle. The hardware timers advance at the instruction cycle rate, Fosc/4. I chose 10MHz to try to make the math a little easier. So far I'm only using fixed point math. I'm trying to avoid using any floating point. Floating point in assembler would quickly turn a fun project into a nightmare. I think that the PIC 18 interrupt latency is 3 instruction cycles. I'll have to double check the PIC 18 data sheet and verify this. There will also be some more latency because I have two interrupts occurring asynchronously. When the pic input pin is triggered an interrupt is generated. This interrupt routine captures the current value of a free running timer. Unfortunately, the pic only has 16 bit timers. I needed 32 bits. Because of this, I generate another interrupt whenever the timer overflows. I use this to manually increment another 16 bits. If an input pin interrupt occurs during a timer rollover there will be a little more delay while the timer rollover is handled. I'm sure there are better ways to code this. Also, internally I think I'm doing something similar what your picpet does. My timer displays the clock rate and other info. Internally I'm just taking a snapshot of a free running timer. I then subtract the last two samples to get the beat time. I do an average of two beats to get the clock rate and finally the difference between two beats to show the beat error. From what you're saying there's an advantage to output the raw timer values. I'd then see a series of steadily increasing values until the timer rolled over. A plot would look like a sawtooth waveform. I'll add another log option to output the raw timer value. I'd definitely be interested in talking more about your picpet and it's isochronous coding. I think this may be getting off-topic for this list. It looks like this list is more about the hardware used for precision time measurement than the software. We could continue this topic off list if you think other members won't be interested. Finally, Here are some pictures of the timer. Back http://mesterhome.com/clock/clock%20timer/Clock%20Timer%20009.JPG Front http://mesterhome.com/clock/clock%20timer/Clock%20Timer%20012.JPG ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] temperature
Hi John, Sorry, I don't have a quick answer to your temperature question. There's time-nuts (http://leapsecond.com/time-nuts.htm), and volt-nuts (https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts), and I think there are Tek and HP test equipment groups, but it sounds like what you want is some sort of temperature-nuts group. If your question(s) about precise temperature measurement cross over to properties of quartz resonators, or performance of quartz and atomic oscillators, or even just practical timing laboratory issues, then it would be ok to post to time-nuts. Most of us timing guys have at one time or another faced serious questions about precise temperature measurement, control, and stability. We would welcome further information or shared experience in this area. I have a hp 2801 and use one or more hp 2804 over GPIB to monitor my best clocks to milli-Kelvin levels. I suspect other time-nuts are also familiar with the 2804 quartz thermometer. I'll cc time-nuts for you. /tvb - Original Message - From: To: t...@leapsecond.com Sent: Thursday, December 05, 2013 10:52 AM Subject: temperature Hi there ... do you know any people or groups who are interested in precision temperature measurement? This would relate specifically to quartz thermometers of the HP type. Thanks, John ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] OT : different Rx and Tx baud rate on same port
Hi, I am looking for current serial adapters that support split baud rates. That is different input and output baud rate. Grateful for suggestions! kind regards, Björn ___ time-nuts mailing 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] OT : different Rx and Tx baud rate on same port
Hi What kind of interface? Bob On Dec 6, 2013, at 7:14 PM, Björn b...@lysator.liu.se wrote: Hi, I am looking for current serial adapters that support split baud rates. That is different input and output baud rate. Grateful for suggestions! kind regards, Björn ___ time-nuts mailing 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] OT : different Rx and Tx baud rate on same port
Björn; What platforms (HW and OS) are we considering? If I were writing the software, I'd seriously consider using two ports. JimT Sent from *my* galaxy (Nexus). On Dec 6, 2013 9:33 PM, Björn b...@lysator.liu.se wrote: Hi, I am looking for current serial adapters that support split baud rates. That is different input and output baud rate. Grateful for suggestions! kind regards, Björn ___ time-nuts mailing 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] OT : different Rx and Tx baud rate on same port
Björn, If you can't find a black box that does this, just use two serial ports: Rx from one and the Tx from the other. On the software side it means opening two devices, but that shouldn't be hard to handle. Note bb-elec.com used to make a cute 4-port serial concentrator that would allow you to configure different baud rates in/out, but I see that's no longer a current product. Of course you could do all this with a micro or SBC, but I assume you're looking for a turn-key device rather than a homebrew project. /tvb - Original Message - From: Björn b...@lysator.liu.se To: time-nuts@febo.com Sent: Friday, December 06, 2013 4:14 PM Subject: [time-nuts] OT : different Rx and Tx baud rate on same port Hi, I am looking for current serial adapters that support split baud rates. That is different input and output baud rate. Grateful for suggestions! kind regards, Björn ___ time-nuts mailing 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] Using a UBlox NEO-6 GPS module for calibrating a PIC microprocessor based timer.
Hi Luke, Monitoring the GPS performance looked like a good start. I have the serial For timing mechanical clocks, you'll find that microseconds, or 100 ns, or 50 meters is plenty accurate. So no worries there. Even with 100 ns GPS receiver accuracy, you can calibrate your crystal oscillators to 0.01 ppm in under a minute. I've looked at Brian Mumford's Microset timer. I think it's the best one available. If I hadn't decided to make my own I'd have bought his. I really Agreed, highly recommended. I use several of Bryan's sensors and timers, in addition to ones of my own design. I'm using a PIC 18F13K22. My code is in assembly language. The external clock is 10MHz. Internally it's running at 40MHz using the 4x PLL. The PIC Yes, those larger PIC's with internal PLL allow you to overcome the Fosc/4 issue. I think that the PIC 18 interrupt latency is 3 instruction cycles. I'll have to double check the PIC 18 data sheet and verify this. There will also be some more latency because I have two interrupts occurring asynchronously. When the pic input pin is triggered an interrupt is For a timer, the interrupt latency number is not really the issue; the key point is if the number is invariant under all conditions. We can talk off-line about your use of multiple interrupts. In general, for precise interrupt-based timing, this is a bad idea. One alternative is using the ECCP (capture time-stamp) feature. But, for your use with timing mechanical clocks, your design is more than adequate. Also, internally I think I'm doing something similar what your picpet does. Probably not. The picPET is based on the 8-pin PIC12 series and does not use interrupts or timers for its timekeeping (which is why it can keep perfect time without the variable latency and jitter issues seen in some microprocessor-based timers). Finally, Here are some pictures of the timer. Nice. Thanks for sharing. /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
