Re: [time-nuts] time transfer over USB
On Tue, 14 May 2013 07:22:26 +0200 Herbert Poetzl herb...@13thfloor.at wrote: If the best-case response time is calibrated out, how good can this get? Microseconds? With 125us latency and a fixed interval, it should be possible to calculate the relation between the transfer intervall (USB clock crystal) and the PPS (or whatever information is transmitted) and thus easily get below the 100us. You can actually get better than that. If you are using a uC at the sending end, you get a transfer completed interrupt. You can time this interrupt and send a second packet to the PC to tell it how long it took for the PC to receive the first packet. Thus getting rid of quite a bit of the uncertainty between the device and the usb controller. Also use a uC with HS USB, as this allows to use micro frames which are 125us long insted of the normal 1ms long frames. Also, use interrupt transferes instead of bulk, as these are prefered over bulk transfere in case of congestion, and have two times as many slots per frame. Oh.. and connect the whole thing to a port on the PC that does _not_ have an internal USB hub. Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] OCXO shock protection
Re: [time-nuts] OCXO shock protection Water heaters must be bolted to the wall studs. Other wise they go over. Several hundred pounds of water is a big mass. Lived there for 50 years. Generally earthquakes are pretty localized and not a huge hazard with just a little thought. You do have to buy earthquake insurance. Costs me about $ 400 per year for a home I still have there. You can suspend the gear on as a pendulum from a single line. That should provide some isolation and also a DIY seismograph. The military shock mount racks are designed to protect a specific load. So may not work. john k6iql - in KS. New place different hazards! -Original Message- From: time-nuts-request time-nuts-requ...@febo.com To: time-nuts time-nuts@febo.com Sent: Sun, May 19, 2013 10:13 pm Subject: time-nuts Digest, Vol 106, Issue 94 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than Re: Contents of time-nuts digest... Today's Topics: 1. Re: Net4501's cheap.. (Tom Clifton) 2. Re: Time Nut Pickens at the MIT Flea ? (Bob Bownes) 3. OCXO shock protection (Perry Sandeen) 4. Re: Time Nut Pickens at the MIT Flea ? (paul swed) 5. Re: OCXO shock protection (Hal Murray) 6. Re: OCXO shock protection (Frederick Bray) 7. Re: OCXO shock protection (Chris Albertson) -- Message: 1 Date: Sun, 19 May 2013 19:10:22 -0700 (PDT) From: Tom Clifton kc0...@yahoo.com To: time-nuts@febo.com time-nuts@febo.com Subject: Re: [time-nuts] Net4501's cheap.. Message-ID: 1369015822.8519.yahoomail...@web161602.mail.bf1.yahoo.com Content-Type: text/plain; charset=iso-8859-1 Seller obviously figured out that somebody feels they are of value and adjusted the selling price to see what he can squeeze out of them. ?I'd suggest making a $20 offer if you want to try to drive the price back down to what is reasonable Message: 6 Date: Sun, 19 May 2013 18:07:51 -0500 From: Didier Juges shali...@gmail.com To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Net4501's cheap... I snatched one for $20 and they are now $59 or best offer. -- Message: 2 Date: Sun, 19 May 2013 22:09:06 -0400 From: Bob Bownes bow...@gmail.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Cc: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Time Nut Pickens at the MIT Flea ? Message-ID: 5b6c53a6-7b8c-47b2-8eb8-94a67f626...@gmail.com Content-Type: text/plain; charset=us-ascii We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: Hello to the group. I did see the leitch video DA's. Was a good price if the DA's were in the case. The other thing to watch out for is that Leitch made all types of DAs digital also. You want the simple vide monitoring DA, Equalizing DAs are OK also delays are a pain. John it was good to see you and Jim. Great Wx. As for the pickens not much at all. I picked up to EGG RB oscillators and warming one up right now to see if it will work. At $20 each worth a try. Other then that parts and the real find a HPIB frame for Tek modules for $20. Been looking for one for quite a while. But really little time-nuttery stuff. Stan one day one way or another would be good to run into you. I also did not see Paul. (The other one who is also a slight time nut) Regards Paul On Sun, May 19, 2013 at 6:55 PM, Andy Bardagjy a...@bardagjy.com wrote: I grabbed a real nice Leitech distribution amplifier - but I took it home and it was empty! I walked back and returned it for a refund, but the seller said he had a whole stack in his office. I was gonna post to the list when I sort it out - it was a real bargin, and he said he might be willing to ship them around. Andy Bardagjy bardagjy.com On Sun, May 19, 2013 at 4:42 PM, Stan, W1LE stanw...@verizon.net wrote: Anyone got any Time Nut quality items at the MIT fleamarket today ? Stan, W1LE Cape Cod __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nuts https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the
Re: [time-nuts] Can I get 1 millisecond accuracy with a USB GPS-18
On Mon, 13 May 2013 12:17:42 -0700 Hal Murray hmur...@megapathdsl.net wrote: Anybody know if uBlox over USB units are available? I just took a quick look and didn't find anything. IIRC all LEA-5 and newer have an USB port for communication. I couldnt find anything in the protocol specs whether it supports interrupts over the USB interface for PPS. Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] Ground loops in measurements?
Moin, A couple of weeks ago, there was a short discussion on bad connectors and cables and the coupled in noise of those. Summarized it said that measurements in the time-nuts scale are very sensitive to even the lowest noise levels and coupled in signals. But, all the measurements we do are done using some sort of coax which have their shield connected to the case of the devices. As the invovled devices in a measurement are also grounded over their power supply this will lead to ground loops and thus a 50/60Hz noise. Also, because loops are good magnetic antennas, a lot of other noise floating around in the ether is coupled in (eg a nearby radio station). How do you handle this kind of problems? Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] Time Nut Pickens at the MIT Flea ?
I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Time Nut Pickens at the MIT Flea ?
Paul, So you were there and I missed you then. It was hard to find anything. Looking in all the corners. Most of its now the monthly repeat stuff that doesn't seem to move. John, You are right it would be a TM5000 3 bay. The color is tek blue, not the brown of the 5000 series. Funny I don't care about color. Now I can plug the AA5010 into a home. Regards Paul On Mon, May 20, 2013 at 8:11 AM, Ziggy zig...@pumpkinbrook.com wrote: I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] Measuring Phase diference between different, GPSDO
Try Stabilant. http://www.amazon.com/Stabilant-5ml-Kit-Makes-30ml/dp/B001E50GQS I have no affiliation with this product. I've used it to fix intermittent connections that drove me crazy. It's not a contact cleaner, and you'll have to read the details to understand what it does. It's also avaliable from Napa auto parts as CE-1. It's not cheap... Last time I used this, it was on an external hard drive case that the sata connectors would need to be wiggled every time I powered it (even tried re-flowing the solder joints!) Put this on it, haven't had to touch the connectors in over a year. If you guys are working on old equipment with sockets and connectors, it's really worth looking at. Dan On 5/18/2013 4:46 PM, time-nuts-requ...@febo.com wrote: Resetting the boards may not do, but resetting the chips that are in sockets probably will, based on my two 5370s Didier KO4BB Mark C. Stephens ma...@non-stop.com.au wrote: It is as you said Bob, I plugged the 5370b in and It flashed a zero then the display and front panel are blank. It has some other equipment in service on top of it so when I get a chance for some downtime, I'll pull it out and reseat the boards. Wish me luck! mark ___ time-nuts mailing 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] Time Nut Pickens at the MIT Flea ?
There are cafe/pizza options in the Strattion Student Center, although seating is somewhat limited. But there are other places in the same building. It's a short walk from the flea site (Mass Ave at Vasser Street) Bldg W-20 -John I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] Time Nut Pickens at the MIT Flea ?
It is surprizingly difficult to find other shoppers at the Flea. I suspoect it's because people sort of 'shop with the flow'- all moving in the same direction. -John = Paul, So you were there and I missed you then. It was hard to find anything. Looking in all the corners. Most of its now the monthly repeat stuff that doesn't seem to move. John, You are right it would be a TM5000 3 bay. The color is tek blue, not the brown of the 5000 series. Funny I don't care about color. Now I can plug the AA5010 into a home. Regards Paul On Mon, May 20, 2013 at 8:11 AM, Ziggy zig...@pumpkinbrook.com wrote: I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] Time Nut Pickens at the MIT Flea ?
Plenty of good stuff in the area; Flour, Area Four, Catalyst, Friendly Toast, Blue Room, CBC, and so on. I live in the area - recent MIT graduate - and would be happy to set something up (though I think my gf's birthday is that day, so maybe not) Andy Bardagjy bardagjy.com On Mon, May 20, 2013 at 8:34 AM, J. Forster j...@quikus.com wrote: There are cafe/pizza options in the Strattion Student Center, although seating is somewhat limited. But there are other places in the same building. It's a short walk from the flea site (Mass Ave at Vasser Street) Bldg W-20 -John I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] Time Nut Pickens at the MIT Flea ?
IMO, it would be good to have any gathering place w/in easy walking distance of the flea. Parking in Cambridge is not easy in the best of times. YMMV, -John = Plenty of good stuff in the area; Flour, Area Four, Catalyst, Friendly Toast, Blue Room, CBC, and so on. I live in the area - recent MIT graduate - and would be happy to set something up (though I think my gf's birthday is that day, so maybe not) Andy Bardagjy bardagjy.com On Mon, May 20, 2013 at 8:34 AM, J. Forster j...@quikus.com wrote: There are cafe/pizza options in the Strattion Student Center, although seating is somewhat limited. But there are other places in the same building. It's a short walk from the flea site (Mass Ave at Vasser Street) Bldg W-20 -John I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] time transfer over USB
On 5/20/13 2:43 AM, Attila Kinali wrote: Oh.. and connect the whole thing to a port on the PC that does _not_ have an internal USB hub. That's a bit of challenge, I suspect.. A casual look at the PCs I have around here running windows all seem to have on-mobo hubs when you check Device Manager. I suspect they are integrated into one of the peripheral chips. ___ time-nuts mailing 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] Time Nut Pickens at the MIT Flea ?
A gentle reminder to keep postings to time-nuts as technical as possible, and on-topic. The occasional mention of upcoming local events or conferences is welcome (it's a great way to build community), but I suggest subsequent details, follow-up, meeting arrangements, and where to get pizza should be done by private email. The list now has 1300 members world-wide. Thanks, /tvb http://leapsecond.com/time-nuts.htm ___ time-nuts mailing 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] time transfer over USB
I suspect the idea is to use a port where no other devices, that is internal, are on the hub. Like you, I never saw a usb port not on a hub. -Original Message- From: Jim Lux jim...@earthlink.net Sender: time-nuts-boun...@febo.com Date: Mon, 20 May 2013 06:14:12 To: time-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] time transfer over USB On 5/20/13 2:43 AM, Attila Kinali wrote: Oh.. and connect the whole thing to a port on the PC that does _not_ have an internal USB hub. That's a bit of challenge, I suspect.. A casual look at the PCs I have around here running windows all seem to have on-mobo hubs when you check Device Manager. I suspect they are integrated into one of the peripheral chips. ___ time-nuts mailing 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] Ground loops in measurements?
Moin Attila, yes ground loops can cause serious measurement problems. And solving those could fill a hole book. Here's what I do in practical: 1.) avoid the loop 2.) if you can't, try harder to avoid it - depending on the problem: break up the dc loop by using capacitors (most often you only need to kill 50/60 Hz so you can possibly insert a C in the shield) - if you need dc current or extremly low frequencies flowing in the shield, use inductors in the shield to get rid of 50/60 Hz - if you have to transfer low frequency rectangular pulses, you have to decide or even to try, what will be the better choice - but that induces new problems if you have to be synchronous to within some ns... - on the lab bench - if you can't avoid loops - make the area of the loop as small as you can to reduce the inducing field - keep shields together - use a well grounded!! metal plate (use iron, if you can) under your experiment and lay the coax cables flat down on it - as far as you can connect all case grounds at one point only - if you are experimenting with low frequency on your bench you can try to not connect the shield on one side of the cable - be aware, that the current now takes another way, so that is practicable in only few situations (and if you fumble around it will change measurement conditions) - use floating power supplies - but remember, they can be coupled to earth or the power line over the stray capacitance of the transformer (rather a problem for higher frequencies than 50/60 Hz) Volker Am 20.05.2013 14:08, schrieb Attila Kinali: Moin, A couple of weeks ago, there was a short discussion on bad connectors and cables and the coupled in noise of those. Summarized it said that measurements in the time-nuts scale are very sensitive to even the lowest noise levels and coupled in signals. But, all the measurements we do are done using some sort of coax which have their shield connected to the case of the devices. As the invovled devices in a measurement are also grounded over their power supply this will lead to ground loops and thus a 50/60Hz noise. Also, because loops are good magnetic antennas, a lot of other noise floating around in the ether is coupled in (eg a nearby radio station). How do you handle this kind of problems? Attila Kinali ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] OCXO shock protection
We will be moving to southern California in the near future. My question if for people who live in that area is do you need to do additional shock mounting for OCXO’s because of the ongoing, usually minor, earth tremors that take place? Hi Perry, Your OCXO will be fine, unless it falls on the floor. Shock mounting won't help because earthquakes are more slow rocking, rolling, or shaking than shock. The bandwidth of the acceleration is quite low, around 1 Hz. Your OCXO, and the shelf holding it, not to mention your house and neighborhood will all enjoy the same ride. I suppose a helium balloon suspended OCXO would be immune. Here's a back-of-the-envelope calculation: The typical OCXO has an acceleration sensitivity on the order of 1e-9 per g. You can easily measure your OCXO by placing it on each of six sides, computing the frequency difference. If the quake is strong, the temporal acceleration is on the order of 0.1 g. See: http://en.wikipedia.org/wiki/Peak_ground_acceleration This means the short-term frequency *modulation* is down at the 1e-10 level, or below (if you orient the OCXO along a less sensitive axis). Most OCXO already have this much short-term noise, so you'd never notice the quake. Even with a low noise OCXO, it takes a very high-resolution phase meter to detect rapid frequency changes at the 1e-11 level. Note there is little or no effect on timing, since the sum of the +/- acceleration over the duration of the quake is essentially zero. The same goes for net change in frequency, unless the OCXO is gets moved or tilted as a result of the quake. Pendulum clocks are much more fun to measure during a quake: http://www.bmumford.com/mset/tech/quake/ My home lab survived a 6.8 quake. If you do sub-cm GPS you may want to double check your coordinates after a strong quake, as your house (and neighborhood) may have moved: http://leapsecond.com/pages/quake/ /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.
Re: [time-nuts] time transfer over USB
On Mon, 20 May 2013 06:14:12 -0700 Jim Lux jim...@earthlink.net wrote: On 5/20/13 2:43 AM, Attila Kinali wrote: Oh.. and connect the whole thing to a port on the PC that does _not_ have an internal USB hub. That's a bit of challenge, I suspect.. A casual look at the PCs I have around here running windows all seem to have on-mobo hubs when you check Device Manager. I suspect they are integrated into one of the peripheral chips. In my experience, it's usually two or 4 ports connected to an internal hub, where at least one is not on a hub at all. You have to try to find out which they are. I dont know any similar tool with windows, but on linux (and i guess *BSD) you can use lsusb to give you a hierarchy of the USB system on your mainboard. There you can see which ports have a hub behind them and which dont. Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] OCXO shock protection
On Mon, 20 May 2013 07:35:18 -0700 Tom Van Baak t...@leapsecond.com wrote: If the quake is strong, the temporal acceleration is on the order of 0.1 g. See: http://en.wikipedia.org/wiki/Peak_ground_acceleration Interesting. This would mean that the usual noise in an office environment is at the same magnitude as an earthquake, just different frequency. (We recently measured slightly less than 0.1g in our office, which is consistent with the number given in Vig's tutorial: 0.01 to 0.1g) Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] silicon/silicon oxide based solid state atomic clocks? (was: Flawed diamonds promise sensory perfection)
On Sat, 11 May 2013 13:50:23 -0700 Brooke Clarke bro...@pacific.net wrote: The first article at RD magazine cites another article in Nature, but it's a $ article. http://www.rdmag.com/news/2013/05/flawed-diamonds-promise-sensory-perfection Solid-state electronic spin coherence time approaching one second http://www.nature.com/ncomms/journal/v4/n4/full/ncomms2771.html Has anyone seen/heard about something similar done with silicon or silicon oxide? I guess that a silicon/si-ox based system would be a lot cheaper to produce, given todays semiconductor industry. The only thing i could dig out that goes into this direction is [1]. But that looks at it from a quantum computing point of view. I guess silicon cannot be used the way diamond is used (ie using a double resonance system) because it's not transparent, and probably too metallic already. Silicon oxide on the other hand is transparent and a very good isolator, hence the electrons would be confined to their atoms. But googling for silicon oxide, defects and spectroscopy i only get results from defects assesment in the semiconductor production. Attila Kinali [1] Atomic clock transitions in silicon-based spin qubits, by Wolfowicz et all, 2013, http://arxiv.org/abs/1301.6567 -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] Ground loops in measurements?
Attila Kinali One effective and sure fire way to deal with ground loops is to use a minature 1:1 50 or 200 ohm (not critical as most instruments are not matched inputs anyway ) in the line from your distribution amplifier to the driven device. Coilcraft has these for both PC and SMT Just drive one side with the source coax and connect the load to the other. They are about a 1/2 inch cube and the PC mount types have leads to which the coax can be simply soldered, or you can get fancy and put in a box with ground isolated connectors. The band width of these devices is typically 1 to 100 MHz or more. Eliminates all 60 Hz transmission that is common mode on the coax. These are not expensive. www.coilcraft.com. They did sell on the web for me about a year ago. -73 john k6iql -Original Message- From: time-nuts-request time-nuts-requ...@febo.com To: time-nuts time-nuts@febo.com Sent: Mon, May 20, 2013 10:28 am Subject: time-nuts Digest, Vol 106, Issue 97 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than Re: Contents of time-nuts digest... Today's Topics: 1. Re: Time Nut Pickens at the MIT Flea ? (J. Forster) 2. Re: time transfer over USB (Jim Lux) 3. Re: Time Nut Pickens at the MIT Flea ? (Tom Van Baak) 4. Re: time transfer over USB (li...@lazygranch.com) 5. Re: Ground loops in measurements? (Volker Esper) 6. Re: OCXO shock protection (Tom Van Baak) 7. Re: time transfer over USB (Attila Kinali) 8. Re: OCXO shock protection (Attila Kinali) -- Message: 1 Date: Mon, 20 May 2013 05:50:07 -0700 (PDT) From: J. Forster j...@quikus.com To: Andy Bardagjy a...@bardagjy.com Cc: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Time Nut Pickens at the MIT Flea ? Message-ID: 56273.12.226.214.5.1369054207.squir...@popaccts.quikus.com Content-Type: text/plain;charset=iso-8859-1 IMO, it would be good to have any gathering place w/in easy walking distance of the flea. Parking in Cambridge is not easy in the best of times. YMMV, -John = Plenty of good stuff in the area; Flour, Area Four, Catalyst, Friendly Toast, Blue Room, CBC, and so on. I live in the area - recent MIT graduate - and would be happy to set something up (though I think my gf's birthday is that day, so maybe not) Andy Bardagjy bardagjy.com On Mon, May 20, 2013 at 8:34 AM, J. Forster j...@quikus.com wrote: There are cafe/pizza options in the Strattion Student Center, although seating is somewhat limited. But there are other places in the same building. It's a short walk from the flea site (Mass Ave at Vasser Street) Bldg W-20 -John I was there as well, but did not see much of interest. That might be because Paul Swed scooped up the good stuff before I could finish the first pass :) Nice find Paul, hope they settle down for you. Would love to see a post-flea get together and put some faces with names, but I don't know of any places nearby. Paul - K9MR On May 19, 2013, at 10:22 PM, paul swed wrote: Good news at least the first EGG RB fired up and after adjusting the synthesizer is locked very nicely. Letting it bake and figuring out the dip switches. They were wrong or purposely offset. Hard to say. Lamp voltage is 12 VDC I suspect thats quite a good number if compared to the old FRS and FRCs I have down in the 5-6V range. The FRS/C run 12 new. Can't really find any documentation, but expected that. Regards Paul WB8TSL On Sun, May 19, 2013 at 10:09 PM, Bob Bownes bow...@gmail.com wrote: We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Message: 2 Date: Mon, 20 May 2013 06:14:12 -0700 From: Jim Lux jim...@earthlink.net To:
Re: [time-nuts] 10Mhz Sine from Square Wave Synthesizer
Hi Andy, The simplest way is to use a low pass filter with a notch capability for the second and third harmonics. You can find the schematic and response for 5 and 10 MHz here: http://www.timeok.it/files/5_and_10mhz_low_pass_notch_filter.pdf ciao, Luciano timeok see: www.timeok.it On Mon, May 20, 2013 at 1:30 AM, Andy Bardagjy a...@bardagjy.com wrote: Hi folks, I recently picked up a Symmetricom SA.22c rubidium oscillator. According to the datasheet, it outputs a square wave with programmable frequency (well you can pick among some set of frequencies). I'd like to build up a small circuit locked to the square wave output which outputs a 10MHz sine wave for use as my house clock for my various instruments (spec an, counter etc). I of course could distribute the square wave, but am concerned about harmonics, among other things. The FE-5680A uses a AD9830A DDS to synthesize its output. Is a DDS the right way to go - in terms of performance, phase noise and so on? I suppose I could do this with a tank or some other analog circuit, but.. Andy Bardagjy bardagjy.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. -- Luciano Timeok visit : www.timeok.it ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] OCXO shock protection
Several co-workers have researched this subject extensively and have published a number of interesting papers on the subject. The other question is what is the nature of seismic activity in general, and specifically in your area. If I am not mistaken the force vectors can vary greatly depending on the geology. http://tf.nist.gov/timefreq/general/pdf/2103.pdf http://tf.nist.gov/timefreq/general/pdf/2328.pdf Enjoy Thomas Knox To: time-nuts@febo.com From: johncr...@aol.com Date: Mon, 20 May 2013 06:39:52 -0400 Subject: Re: [time-nuts] OCXO shock protection Re: [time-nuts] OCXO shock protection Water heaters must be bolted to the wall studs. Other wise they go over. Several hundred pounds of water is a big mass. Lived there for 50 years. Generally earthquakes are pretty localized and not a huge hazard with just a little thought. You do have to buy earthquake insurance. Costs me about $ 400 per year for a home I still have there. You can suspend the gear on as a pendulum from a single line. That should provide some isolation and also a DIY seismograph. The military shock mount racks are designed to protect a specific load. So may not work. john k6iql - in KS. New place different hazards! -Original Message- From: time-nuts-request time-nuts-requ...@febo.com To: time-nuts time-nuts@febo.com Sent: Sun, May 19, 2013 10:13 pm Subject: time-nuts Digest, Vol 106, Issue 94 Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than Re: Contents of time-nuts digest... Today's Topics: 1. Re: Net4501's cheap.. (Tom Clifton) 2. Re: Time Nut Pickens at the MIT Flea ? (Bob Bownes) 3. OCXO shock protection (Perry Sandeen) 4. Re: Time Nut Pickens at the MIT Flea ? (paul swed) 5. Re: OCXO shock protection (Hal Murray) 6. Re: OCXO shock protection (Frederick Bray) 7. Re: OCXO shock protection (Chris Albertson) -- Message: 1 Date: Sun, 19 May 2013 19:10:22 -0700 (PDT) From: Tom Clifton kc0...@yahoo.com To: time-nuts@febo.com time-nuts@febo.com Subject: Re: [time-nuts] Net4501's cheap.. Message-ID: 1369015822.8519.yahoomail...@web161602.mail.bf1.yahoo.com Content-Type: text/plain; charset=iso-8859-1 Seller obviously figured out that somebody feels they are of value and adjusted the selling price to see what he can squeeze out of them. ?I'd suggest making a $20 offer if you want to try to drive the price back down to what is reasonable Message: 6 Date: Sun, 19 May 2013 18:07:51 -0500 From: Didier Juges shali...@gmail.com To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Net4501's cheap... I snatched one for $20 and they are now $59 or best offer. -- Message: 2 Date: Sun, 19 May 2013 22:09:06 -0400 From: Bob Bownes bow...@gmail.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Cc: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Time Nut Pickens at the MIT Flea ? Message-ID: 5b6c53a6-7b8c-47b2-8eb8-94a67f626...@gmail.com Content-Type: text/plain; charset=us-ascii We should plan a Time-Nuts BOF lunch after the next flea. Saw little TN gear @ Dayton save one Efretom RBI time base for $1800 and a few 10811s of dubious quality for $50 ea. the dents put me off gambling on one since I was given or the afternoon before! ;) On May 19, 2013, at 21:50, paul swed paulsw...@gmail.com wrote: Hello to the group. I did see the leitch video DA's. Was a good price if the DA's were in the case. The other thing to watch out for is that Leitch made all types of DAs digital also. You want the simple vide monitoring DA, Equalizing DAs are OK also delays are a pain. John it was good to see you and Jim. Great Wx. As for the pickens not much at all. I picked up to EGG RB oscillators and warming one up right now to see if it will work. At $20 each worth a try. Other then that parts and the real find a HPIB frame for Tek modules for $20. Been looking for one for quite a while. But really little time-nuttery stuff. Stan one day one way or another would be good to run into you. I also did not see Paul. (The other one who is also a slight time nut) Regards Paul On Sun, May 19, 2013 at 6:55 PM, Andy Bardagjy a...@bardagjy.com wrote: I grabbed a real nice Leitech distribution amplifier - but I took it home and it was empty! I
Re: [time-nuts] aging/failure of un-powered xtal oscillators?
If there are plenty of them, I'd recommend dissecting one to see how well they're made, and what sort of components are inside. If the crystal is hermetically sealed, it's probably OK. If there are any aluminum electrolytic caps in there, they may be no good. Most other parts from that era should be OK. If possible, you should pretest a bunch of them to see if they seem up to snuff. Ed ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Ground loops in measurements?
Anyone who is serious about Time and Freq has run into ground loop problems, and finding a solution is often more Art then Science A common solution is star grounding, Another approach is grid work grounding, another possible solution is to isolate each instrument. Most often some trial and error is required, and nothing is as valuable as the intuition that comes from years of experience. As you experiment, documenting each change can often help not only towards a immediate solution, but also if problems arise from future changes in your system. Thomas Knox Date: Mon, 20 May 2013 14:08:03 +0200 From: att...@kinali.ch To: time-nuts@febo.com Subject: [time-nuts] Ground loops in measurements? Moin, A couple of weeks ago, there was a short discussion on bad connectors and cables and the coupled in noise of those. Summarized it said that measurements in the time-nuts scale are very sensitive to even the lowest noise levels and coupled in signals. But, all the measurements we do are done using some sort of coax which have their shield connected to the case of the devices. As the invovled devices in a measurement are also grounded over their power supply this will lead to ground loops and thus a 50/60Hz noise. Also, because loops are good magnetic antennas, a lot of other noise floating around in the ether is coupled in (eg a nearby radio station). How do you handle this kind of problems? Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] apple Xcode
Have any tnuts used the Apple Xcode programming setup? If so, quick comments? tnx Don -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. 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] Ground loops in measurements?
Hi Coax is interesting stuff. The shielding is only good down to some lower frequency limit. For anything practical that's going to be 100 KHz. At the frequencies you *should* use coax at, transformer coupling is the easy way to break the ground loop. In this era of cell phones all over the place, a transformer plus some sort of common mode choke is the standard approach. For things like 1 pps, you should be using some sort of balanced transmission. Twisted pair, or better, shielded twisted pair. You can either run into a balanced receiver IC and dc couple or into a transformer and do something a bit fancier. With the IC you have a maximum voltage offset that can be tolerated. With the transformer you have the cost / delay / possible error in picking up the edges. If your environment is noisy enough, you may have to transport your pps on some sort of carrier. RF and optical both have their fans. None of that is going to be easy. The alternative is to do what you would do in a screen room. Single point ground, everything tied tightly together. Put reasonable filtering on everything in and out. Tie the filters to the common ground point. This also is not easy, but possibly not as hard as redesigning the ins and outs of every box in sight. I have seen this approach used on some *very* large systems. A some what extreme approach (that I have seen used). Forget about all the shielding and stuff. Buy a farm, put up a small metal shack in the middle of a large field. Bring a hand cart with batteries. Run everything on a big copper covered table. Lots of ways to go. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Attila Kinali Sent: Monday, May 20, 2013 8:08 AM To: time-nuts@febo.com Subject: [time-nuts] Ground loops in measurements? Moin, A couple of weeks ago, there was a short discussion on bad connectors and cables and the coupled in noise of those. Summarized it said that measurements in the time-nuts scale are very sensitive to even the lowest noise levels and coupled in signals. But, all the measurements we do are done using some sort of coax which have their shield connected to the case of the devices. As the invovled devices in a measurement are also grounded over their power supply this will lead to ground loops and thus a 50/60Hz noise. Also, because loops are good magnetic antennas, a lot of other noise floating around in the ether is coupled in (eg a nearby radio station). How do you handle this kind of problems? Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] RB reference info on EGG TS-RFS
Several years ago there was a thread on EGG RBs. But no documentation was ever shared. Looking at the web there seems little still. However at one time EGG might have been a good reference and company. Not interested in what happened to the company its in the threads. Did anyone ever find technical docs on these units? I have one powered up and it seems to do quite well. But to get it to lock requires a power cycle after its warmed up. Regards Paul WB8TSL ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Trimble Thunderbolt, any easy way to create 500 MHz reference from one?
I assume the question is about going from 10 Mhz to 500 MHz. The possible solutions depend on how clean the result has to be. For counting grade use, this has been done in a number of test instruments like the HP5345A and HP5370A that I'm familiar with, and certainly others. If you look at the multiplier or PLL systems in equipment that does this, you can get an idea of what's involved. It takes quite a bit of circuitry to provide a really clean output. If you already have such an instrument in service, you can modify it to tap off the 500 MHz, buffer it up, and provide an external connection for it. This won't be enough if you need a dedicated or more compact built-in source, but if you can find a carcass of one of these instruments, or just the appropriate boards, you can build up a unit that should be quite good. Of course, any synthesizer that covers that frequency could do the job directly. One of my favorite oldies is the Wavetek 3000 or 3001 that reaches 520 MHz - I have acquired a couple over the years for very cheap. These are tall, half-rack width, so not very compact, but could be cheap enough to dedicate to an application. If it must be very small and modern, you should be able to find off-shelf a complete phase-locked fixed 500 MHz or programmable module, ready to go, but it will be quite expensive new. If you want to start from scratch, I'd recommend looking for an off-shelf SAW-resonator based VCSO from an RF vendor (expensive new, but maybe can be found surplus), and a PLL IC such as those available from Analog Devices and National (now p/o Texas Instruments). Ed ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] apple Xcode
If you are going to produce Mac or IOS apps you don't have a choice. You pretty much have to use it.If you are building portable apps I tend to just use terminal sessions and a text editor and GNU's autoconf to create the .configure files. Depends on what you are doing On Mon, May 20, 2013 at 9:53 AM, Don Latham d...@montana.com wrote: Have any tnuts used the Apple Xcode programming setup? If so, quick comments? tnx Don -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. 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. -- 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] 10Mhz Sine from Square Wave Synthesizer
Alright, so it seems that it's possible the Symmetricom SA.22c that I've got might be set to 9.8304MHz. That may be programmable to 10MHz, but it might require a DDS otherwise. Nevertheless, if the oscillator is set to 10MHz it seems the consensus is to construct a LPF. Luciano, thank you for sharing your design, did you wind your own inductors? Odd values.. Typically when designing filters I start by fixing the inductor values and work backwards... John, thanks for your input, you reminded me that LFP performance often depends on source impedance. To the MMIC amplifier, you'd be amazed what you can do with an opamp these days. I was amazed reading the datasheet for the LTC6409 a 10GHz GBW, 1.1nV/sqrt(hz) fully differential opamp. With a gain of one, the frequency response is totally flat out to 1GHz. http://cds.linear.com/docs/en/datasheet/6409fa.pdf Perhaps something like a LT6600-15 might be a complete solution for me - it's a fully differential amplifier with a 15Mhz 4 pole LPF. http://www.linear.com/product/LT6600-15 Thanks for your input, I'll be sure to keep everyone posted on my project's progress. Andy Bardagjy bardagjy.com On Mon, May 20, 2013 at 12:03 PM, Luciano Paramithiotti timeok...@gmail.com wrote: Hi Andy, The simplest way is to use a low pass filter with a notch capability for the second and third harmonics. You can find the schematic and response for 5 and 10 MHz here: http://www.timeok.it/files/5_and_10mhz_low_pass_notch_filter.pdf ciao, Luciano timeok see: www.timeok.it On Mon, May 20, 2013 at 1:30 AM, Andy Bardagjy a...@bardagjy.com wrote: Hi folks, I recently picked up a Symmetricom SA.22c rubidium oscillator. According to the datasheet, it outputs a square wave with programmable frequency (well you can pick among some set of frequencies). I'd like to build up a small circuit locked to the square wave output which outputs a 10MHz sine wave for use as my house clock for my various instruments (spec an, counter etc). I of course could distribute the square wave, but am concerned about harmonics, among other things. The FE-5680A uses a AD9830A DDS to synthesize its output. Is a DDS the right way to go - in terms of performance, phase noise and so on? I suppose I could do this with a tank or some other analog circuit, but.. Andy Bardagjy bardagjy.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. -- Luciano Timeok visit : www.timeok.it ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] Ground loops in measurements?
Hi Bob whats the problem at low freqs ?? I thought leakage was a function of the size of the holesv the wavelengthor are we into braid skin effect below 100kHz?? so as not to drag this OT a reference will suffice in answer. Best Wishes Alan G3NYK - Original Message - From: Bob Camp li...@rtty.us To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Sent: Monday, May 20, 2013 6:00 PM Subject: Re: [time-nuts] Ground loops in measurements? Hi Coax is interesting stuff. The shielding is only good down to some lower frequency limit. For anything practical that's going to be 100 KHz. At the frequencies you *should* use coax at, transformer coupling is the easy way to break the ground loop. In this era of cell phones all over the place, a transformer plus some sort of common mode choke is the standard approach. For things like 1 pps, you should be using some sort of balanced transmission. Twisted pair, or better, shielded twisted pair. You can either run into a balanced receiver IC and dc couple or into a transformer and do something a bit fancier. With the IC you have a maximum voltage offset that can be tolerated. With the transformer you have the cost / delay / possible error in picking up the edges. If your environment is noisy enough, you may have to transport your pps on some sort of carrier. RF and optical both have their fans. None of that is going to be easy. The alternative is to do what you would do in a screen room. Single point ground, everything tied tightly together. Put reasonable filtering on everything in and out. Tie the filters to the common ground point. This also is not easy, but possibly not as hard as redesigning the ins and outs of every box in sight. I have seen this approach used on some *very* large systems. A some what extreme approach (that I have seen used). Forget about all the shielding and stuff. Buy a farm, put up a small metal shack in the middle of a large field. Bring a hand cart with batteries. Run everything on a big copper covered table. Lots of ways to go. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Attila Kinali Sent: Monday, May 20, 2013 8:08 AM To: time-nuts@febo.com Subject: [time-nuts] Ground loops in measurements? Moin, A couple of weeks ago, there was a short discussion on bad connectors and cables and the coupled in noise of those. Summarized it said that measurements in the time-nuts scale are very sensitive to even the lowest noise levels and coupled in signals. But, all the measurements we do are done using some sort of coax which have their shield connected to the case of the devices. As the invovled devices in a measurement are also grounded over their power supply this will lead to ground loops and thus a 50/60Hz noise. Also, because loops are good magnetic antennas, a lot of other noise floating around in the ether is coupled in (eg a nearby radio station). How do you handle this kind of problems? Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] apple Xcode
Don-- As others have offered, if you're developing for iOS or OSX, you have little choice. It has a comprehensive suite of tools -- for some, too comprehensive, leading to that old adage about how to eat an elephant -- one bite at a time. The entire Xcode suite has a large learning curve, yet the individual tools are approachable, so you can take it a step at a time. While I'll do stuff at the command line on Linux systems, I'll use the tools Xcode provides for me when I'm on the Mac. 73-- Bob K6RTM ___ time-nuts mailing 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] 10Mhz Sine from Square Wave Synthesizer
Hi Andy, If it is at 9.8304 MHz, don't even consider trying to fool with anything inside. While it does have a DDS inside, it is of the newer design where the DDS is inside the loop that determines frequency for locking the Rubidium. It requires a crystal, coil and firmware change to move it to 10 MHz. Unless you want to spend some big money, Symmetricom will not help you at all. How do I know ? Well, I have one and tried ! Even got the proper crystal sent to me, but did not get any firmware. Also there may be a super small surface mount coil that needs to be changed to make the replacement crystal oscillate. The 9.8304 MHz is related to various baud rates and also some clocking frequencies for sound cards. So, don't throw it away as it is still useful. If nothing else you could phase lock a 10 MHz oscillator to it as there is a connecting ratio. BillWB6BNQ Andy Bardagjy wrote: Alright, so it seems that it's possible the Symmetricom SA.22c that I've got might be set to 9.8304MHz. That may be programmable to 10MHz, but it might require a DDS otherwise. Nevertheless, if the oscillator is set to 10MHz it seems the consensus is to construct a LPF. Luciano, thank you for sharing your design, did you wind your own inductors? Odd values.. Typically when designing filters I start by fixing the inductor values and work backwards... John, thanks for your input, you reminded me that LFP performance often depends on source impedance. To the MMIC amplifier, you'd be amazed what you can do with an opamp these days. I was amazed reading the datasheet for the LTC6409 a 10GHz GBW, 1.1nV/sqrt(hz) fully differential opamp. With a gain of one, the frequency response is totally flat out to 1GHz. http://cds.linear.com/docs/en/datasheet/6409fa.pdf Perhaps something like a LT6600-15 might be a complete solution for me - it's a fully differential amplifier with a 15Mhz 4 pole LPF. http://www.linear.com/product/LT6600-15 Thanks for your input, I'll be sure to keep everyone posted on my project's progress. Andy Bardagjy bardagjy.com On Mon, May 20, 2013 at 12:03 PM, Luciano Paramithiotti timeok...@gmail.com wrote: Hi Andy, The simplest way is to use a low pass filter with a notch capability for the second and third harmonics. You can find the schematic and response for 5 and 10 MHz here: http://www.timeok.it/files/5_and_10mhz_low_pass_notch_filter.pdf ciao, Luciano timeok see: www.timeok.it On Mon, May 20, 2013 at 1:30 AM, Andy Bardagjy a...@bardagjy.com wrote: Hi folks, I recently picked up a Symmetricom SA.22c rubidium oscillator. According to the datasheet, it outputs a square wave with programmable frequency (well you can pick among some set of frequencies). I'd like to build up a small circuit locked to the square wave output which outputs a 10MHz sine wave for use as my house clock for my various instruments (spec an, counter etc). I of course could distribute the square wave, but am concerned about harmonics, among other things. The FE-5680A uses a AD9830A DDS to synthesize its output. Is a DDS the right way to go - in terms of performance, phase noise and so on? I suppose I could do this with a tank or some other analog circuit, but.. Andy Bardagjy bardagjy.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. -- Luciano Timeok visit : www.timeok.it ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing 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] 10Mhz Sine from Square Wave Synthesizer
Andy - Glad to be of some small help. A couple of remarks re your comments John, thanks for your input, you reminded me that LFP performance often depends on source impedance. To the MMIC amplifier, you'd be amazed what you can do with an opamp these days. I was amazed reading the datasheet for the LTC6409 a 10GHz GBW, 1.1nV/sqrt(hz) fully differential opamp. With a gain of one, the frequency response is totally flat out to 1GHz. No actually I would not. I suggested the RF MMIC like one of the Mini-Circuits types because they have enough gain to recover the insertion loss of the input pad and the filter. They are also stable as a house not located in California. That leaves some gain margin for you to pad the output down to the desired level or to split it. As for the super duper chips methinks it is best to use no more performance capability than you need. Other wise you end up fighting oscillations, termination issues, and the necessity for very specific layout techniques. The hottest device is not always easiest to apply. Actually a 2N in common emitter will give more than 20 dB of gain and 100 mW out at 10 MHz and no microwave stability issues. It is just a matter of what is easiest for you to design and implement. -73 john k6iql ___ time-nuts mailing 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] apple Xcode
Oh, you can do it, but you really need to know what you're doing. As the prev poster said, it depends on what you are doing. Simple compiles are straightforward, autoconf if its a bit more complex, use Xcode. If you are doing work on an app that needs a GUI, Xcode makes it easy. On May 20, 2013, at 13:39, Chris Albertson albertson.ch...@gmail.com wrote: If you are going to produce Mac or IOS apps you don't have a choice. You pretty much have to use it.If you are building portable apps I tend to just use terminal sessions and a text editor and GNU's autoconf to create the .configure files. Depends on what you are doing On Mon, May 20, 2013 at 9:53 AM, Don Latham d...@montana.com wrote: Have any tnuts used the Apple Xcode programming setup? If so, quick comments? tnx Don -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. 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. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Ground loops in measurements?
A couple of good references regarding noise minimization in electronic systems are: Grounding and Shielding: Circuits and Interference by Ralph Morrison Noise Reduction Techniques in Electronic Systems by Henry W. Ott And the old fallback has been MIL-HDB-419 volumes I and II which mostly addresses facility installation but does provide some insight to good grounding practices for same. If you do have in interest in facilities grounding, the Verizon Plant Practices manuals (which are sometimes found on the Web) are also good as is the Motorola R56 installation standard. My references were mainly the two books by Morrison (best) and Ott when I was designing and building astronomical instrumentation where we had to get our detector noise levels down below 10 electrons when measuring light levels from stars. Greg This message was sent using IMP, the Internet Messaging Program. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Ground loops in measurements?
Hi The braid becomes less effective at lower frequencies due to skin effect. Once that happens you have a magnetic loop that is not as effective at rejecting signals as a twisted pair. Looking at it another way, the threat signal is induced on the shield (braid) and it penetrates to couple to the center conductor. There are a couple of other ways to look at it, they all ultimately come back to the same point. There are a few other odd things that happen as well as you drop frequency, none of them really very helpful for moving signals. --- Now - is it actually a problem or not? As always, that depends. Most of the nasty stuff in a 1 pps is in the edges. That energy (with a fast edge) is nicely captured by the coax. The low frequency stuff is not captured as well, but it also doesn't couple all that well either. Making a transformer work to 1 Hz isn't very easy. So, coax is fine for getting the signal to it's destination. It's only when you look at the ground loops and threat signals that there could be an issue. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Alan Melia Sent: Monday, May 20, 2013 2:50 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Ground loops in measurements? Hi Bob whats the problem at low freqs ?? I thought leakage was a function of the size of the holesv the wavelengthor are we into braid skin effect below 100kHz?? so as not to drag this OT a reference will suffice in answer. Best Wishes Alan G3NYK - Original Message - From: Bob Camp li...@rtty.us To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Sent: Monday, May 20, 2013 6:00 PM Subject: Re: [time-nuts] Ground loops in measurements? Hi Coax is interesting stuff. The shielding is only good down to some lower frequency limit. For anything practical that's going to be 100 KHz. At the frequencies you *should* use coax at, transformer coupling is the easy way to break the ground loop. In this era of cell phones all over the place, a transformer plus some sort of common mode choke is the standard approach. For things like 1 pps, you should be using some sort of balanced transmission. Twisted pair, or better, shielded twisted pair. You can either run into a balanced receiver IC and dc couple or into a transformer and do something a bit fancier. With the IC you have a maximum voltage offset that can be tolerated. With the transformer you have the cost / delay / possible error in picking up the edges. If your environment is noisy enough, you may have to transport your pps on some sort of carrier. RF and optical both have their fans. None of that is going to be easy. The alternative is to do what you would do in a screen room. Single point ground, everything tied tightly together. Put reasonable filtering on everything in and out. Tie the filters to the common ground point. This also is not easy, but possibly not as hard as redesigning the ins and outs of every box in sight. I have seen this approach used on some *very* large systems. A some what extreme approach (that I have seen used). Forget about all the shielding and stuff. Buy a farm, put up a small metal shack in the middle of a large field. Bring a hand cart with batteries. Run everything on a big copper covered table. Lots of ways to go. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Attila Kinali Sent: Monday, May 20, 2013 8:08 AM To: time-nuts@febo.com Subject: [time-nuts] Ground loops in measurements? Moin, A couple of weeks ago, there was a short discussion on bad connectors and cables and the coupled in noise of those. Summarized it said that measurements in the time-nuts scale are very sensitive to even the lowest noise levels and coupled in signals. But, all the measurements we do are done using some sort of coax which have their shield connected to the case of the devices. As the invovled devices in a measurement are also grounded over their power supply this will lead to ground loops and thus a 50/60Hz noise. Also, because loops are good magnetic antennas, a lot of other noise floating around in the ether is coupled in (eg a nearby radio station). How do you handle this kind of problems? Attila Kinali -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ time-nuts mailing 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] apple Xcode
Got it. Thanks, everyone. Don bownes Oh, you can do it, but you really need to know what you're doing. As the prev poster said, it depends on what you are doing. Simple compiles are straightforward, autoconf if its a bit more complex, use Xcode. If you are doing work on an app that needs a GUI, Xcode makes it easy. On May 20, 2013, at 13:39, Chris Albertson albertson.ch...@gmail.com wrote: If you are going to produce Mac or IOS apps you don't have a choice. You pretty much have to use it.If you are building portable apps I tend to just use terminal sessions and a text editor and GNU's autoconf to create the .configure files. Depends on what you are doing On Mon, May 20, 2013 at 9:53 AM, Don Latham d...@montana.com wrote: Have any tnuts used the Apple Xcode programming setup? If so, quick comments? tnx Don -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. 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. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. If you don't know what it is, don't poke it. Ghost in the Shell Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Server Issues?
Is anyone else seeing posts to this list showing up many hours to days late? -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.
Re: [time-nuts] Symmetricom TS2100-GPS - 1PPS has 10uS offset
Hi Esa, Sorry, I haven't tracked this group for a while. Too much work :-) You are intuitive. I expect that the TS21 is triggering on the wrong edge. Way, way back when the TS21 was invented, we were using an external Acutime antenna that had an open collector pps, hence falling edge trigger. When we added support for an onboard gps, they muxed the two 1pps sources together and we had an incompatible trigger logic problem. The way I fixed it at the time was to empirically measure the pulse width and use the antenna delay compensation field to correct the pps. This value was stored in e2 at mfg time based on gps receiver module. At some point, your unit must have not been set or been set to incorrect value or had its gps receiver replaced. Is there an antenna prop delay command available you can use? Greg Dowd | Symmetricom®, Inc. Staff Scientist 2300 Orchard Parkway, San Jose, CA 95131 Direct: 408.964.7643 gd...@symmetricom.com | www.symmetricom.com Symmetricom. Leading the world in precise time solutions. -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Esa Heikkinen Sent: Friday, May 10, 2013 11:06 AM To: time-nuts@febo.com Subject: [time-nuts] Symmetricom TS2100-GPS - 1PPS has 10uS offset Hello! I bought Symmetricom Tymserve TS2100-GPS some time ago. When comparing it's 1PPS with Thunderbolt they are not in sync: http://www.amigazone.fi/files/gpsdo/ts2100-pps-offset.png Symmetricom seems to be always about 10 uSec ahead. If I turn of the power and then on again, it will be in sync very short moment after the tracking led is turned in. But then it will always roll itself at 10 uSec ahead and lock there, when the locked led turns on. It seems that it has somehow wrong GPS PPS offset or maybe it's folloring the 1PPS signal from it's internal GPS from the wrong edge (this is just my guess; Thunderbolt has 10 uSec long PPS signal, maybe the internal GPS as well?) I understand that TS2100 is not as accurate PPS source as Thunderbolt. But it's manual claims that 1PPS accuracy should be 1 uS. So this is clearly out of spec. This is strange because the Symmetricom seems to be high quality product. Obviously not? Is there any way to fix this by adjusting some offset with telnet etc? If not, maybe I try to invert the 1PPS from internal GPS. Or if someone knows how to use Thunderbolt as a time source, I could use that and remove the internal GPS... -- 73s! Esa OH4KJU ___ time-nuts mailing 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] apple Xcode
Same here If you are building apps for apple you don't have any options other than to use XcodeFor portable code just use GNU autoconf to build GCC Sent from my iPhone On May 20, 2013, at 1:39 PM, Chris Albertson albertson.ch...@gmail.com wrote: If you are going to produce Mac or IOS apps you don't have a choice. You pretty much have to use it.If you are building portable apps I tend to just use terminal sessions and a text editor and GNU's autoconf to create the .configure files. Depends on what you are doing On Mon, May 20, 2013 at 9:53 AM, Don Latham d...@montana.com wrote: Have any tnuts used the Apple Xcode programming setup? If so, quick comments? tnx Don -- Neither the voice of authority nor the weight of reason and argument are as significant as experiment, for thence comes quiet to the mind. De Erroribus Medicorum, R. Bacon, 13th century. 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. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Server Issues?
yes On Mon, May 20, 2013 at 6:15 PM, J. Forster j...@quikus.com wrote: Is anyone else seeing posts to this list showing up many hours to days late? -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 mailing 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] Server Issues?
Yes. My most recent post showed up many hours (maybe six or eight) after I sent it. That was perhaps two or three weeks ago. 73, Brent, KD0GLS, Minneapolis On 20 May 2013, at 18:18, J. Forster wrote: Is anyone else seeing posts to this list showing up many hours to days late? -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 mailing 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] Server Issues?
I'm not aware of any specific server issues here (the configuration is fairly stock Debian with Mailman and Postfix) but there can be delays due to the vagaries of the internet and there are interactions that can cause delays for some folks and not others. I'll keep an eye on things to see if I can spot any problems at this end. John On May 20, 2013, at 7:26 PM, KD0GLS kd0...@mninter.net wrote: Yes. My most recent post showed up many hours (maybe six or eight) after I sent it. That was perhaps two or three weeks ago. 73, Brent, KD0GLS, Minneapolis On 20 May 2013, at 18:18, J. Forster wrote: Is anyone else seeing posts to this list showing up many hours to days late? -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 mailing 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] Server Issues?
Yes J. Forster wrote: Is anyone else seeing posts to this list showing up many hours to days late? -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 mailing 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] Server Issues?
A couple of messages posted Friday, 5/17, showed up today 5/20, just before I posted the query. The issue is relatively recent... since late last week. -John I'm not aware of any specific server issues here (the configuration is fairly stock Debian with Mailman and Postfix) but there can be delays due to the vagaries of the internet and there are interactions that can cause delays for some folks and not others. I'll keep an eye on things to see if I can spot any problems at this end. John On May 20, 2013, at 7:26 PM, KD0GLS kd0...@mninter.net wrote: Yes. My most recent post showed up many hours (maybe six or eight) after I sent it. That was perhaps two or three weeks ago. 73, Brent, KD0GLS, Minneapolis On 20 May 2013, at 18:18, J. Forster wrote: Is anyone else seeing posts to this list showing up many hours to days late? -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 mailing 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] display on sale
Most of you like to DIY, but this might be of interest to some. http://www.symmetricom.com/lp/gbu/email/time-display-promo-landing-page/?emailid=GBU078_NTD_Promo_ProdPglead_source=Web J.D. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
