Re: [time-nuts] time-nuts Digest, Vol 101, Issue 154
Said, not sure where the noise is coming from but I suspect it's from the MV89 OCXO itself which was only powered up for 10 hours when the data was collected. The BVA reference and the counter (an HP5370B) have performed significantly better on other occasions. When I have some time over the holidays I'll take another look at this and confirm that the BVA and HP5370B are working as they should. I'll likely compare the BVA to another OCXO using another HP5370B at the same time I'm comparing the BVA to the MV89, then swap the two counters and repeat the measurements, but I didn't have time for that this am (: I saw your request for data re OCXO's and fans and this gave me the incentive to spend a few minutes to power up one of my MV89's, then blow some air over it and collect a bit of data the next morning (: As a side note I've got two Z3805's in service and yes they are great performers over short time intervals (one of them seems to match the short term performance of my BVA on many occasions.) I need to save my pennies for better counter / analyzer as well as the HP5370B is of little use at tau's of less than 100 seconds or so (: Regards Mark S --- On Fri, 12/21/12, time-nuts-requ...@febo.com time-nuts-requ...@febo.com wrote: From: time-nuts-requ...@febo.com time-nuts-requ...@febo.com Subject: time-nuts Digest, Vol 101, Issue 154 To: time-nuts@febo.com Received: Friday, December 21, 2012, 10:23 AM 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-nuts Digest, Vol 101, Issue 152 (Said Jackson) 2. Re: Brooks Shera (Chris Albertson) 3. Re: Z3805A cooling requirements? (Volker Esper) 4. Re: A Day in the Life of Five PPS Sources.. (Tom Miller) 5. Re: time-nuts Digest, Vol 101, Issue 152 (Volker Esper) -- Message: 1 Date: Fri, 21 Dec 2012 09:53:51 -0800 From: Said Jackson saidj...@aol.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Cc: time-nuts@febo.com time-nuts@febo.com Subject: Re: [time-nuts] time-nuts Digest, Vol 101, Issue 152 Message-ID: 6e6305fd-df54-44d5-9ceb-5d4aeb5ae...@aol.com Content-Type: text/plain; charset=us-ascii Mark, Your plot still shows excursions of +/-1E-010, about 100x higher base noise than the Z3801A/Z3805A are capable of achieving. Wonder where that noise is coming from? This noise is probably much higher than the thermal effects. The original post was the question does my Z380xA have reduced stability if I add a fan or similar, I think the answer is shown to be yes. Volker, I wonder if you also see fan-induced spurs in the phase noise from 1Hz to 100Hz. I would not be surprised if the fan vibration adds significant spurs to the 10811A crystal. Bye, Said Sent from my iPad On Dec 21, 2012, at 9:42 AM, Mark Spencer mspencer12...@yahoo.ca wrote: This plot should show the frequency change more clearly. (Same data just presented differently.) It seems to me that the noise goes may be going down a bit for a minute or so just after the fan is turned on but I don't believe these plots provide conclusive evidence of this. Regards Mark Spencer Message: 7 Date: Fri, 21 Dec 2012 09:27:29 -0800 From: Said Jackson saidj...@aol.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] Z3805A cooling requirements? Message-ID: 83ce0384-2996-4155-b51b-9d79910b2...@aol.com Content-Type: text/plain; charset=us-ascii Great plots guys! Looking at these results I think my original claim still holds: ADEV goes up when a fan is involved versus no fan, even on a double oven 10811.. Clearly visible on the 10811, maybe not so much on the MV89 but that unit seems to have frequency moves into the xE-010 region on Marks plot so maybe the effect is just a bit hidden? Bye, Said Sent from my iPad On Dec 21, 2012, at 5:44 AM, Volker Esper ail...@t-online.de wrote: ...and the picture of the experiment... The picture enclosed can give you a first impression. What we see is the difference time between the GPS signal and the OCXO (blue) (PPS-TI), which is an HP 10811. In red we can see the EFC. The total span is 24 h. Before I applied the fan, the noise was at a maximum of about +/- 20
Re: [time-nuts] time-nuts Digest, Vol 101, Issue 154
Mark, Could you please post a photograph of your experiment? Thanks Volker Am 21.12.2012 20:05, schrieb Mark Spencer: Said, not sure where the noise is coming from but I suspect it's from the MV89 OCXO itself which was only powered up for 10 hours when the data was collected. The BVA reference and the counter (an HP5370B) have performed significantly better on other occasions. When I have some time over the holidays I'll take another look at this and confirm that the BVA and HP5370B are working as they should. I'll likely compare the BVA to another OCXO using another HP5370B at the same time I'm comparing the BVA to the MV89, then swap the two counters and repeat the measurements, but I didn't have time for that this am (: I saw your request for data re OCXO's and fans and this gave me the incentive to spend a few minutes to power up one of my MV89's, then blow some air over it and collect a bit of data the next morning (: As a side note I've got two Z3805's in service and yes they are great performers over short time intervals (one of them seems to match the short term performance of my BVA on many occasions.) I need to save my pennies for better counter / analyzer as well as the HP5370B is of little use at tau's of less than 100 seconds or so (: Regards Mark S --- On Fri, 12/21/12, time-nuts-requ...@febo.comtime-nuts-requ...@febo.com wrote: From: time-nuts-requ...@febo.comtime-nuts-requ...@febo.com Subject: time-nuts Digest, Vol 101, Issue 154 To: time-nuts@febo.com Received: Friday, December 21, 2012, 10:23 AM 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-nuts Digest, Vol 101, Issue 152 (Said Jackson) 2. Re: Brooks Shera (Chris Albertson) 3. Re: Z3805A cooling requirements? (Volker Esper) 4. Re: A Day in the Life of Five PPS Sources.. (Tom Miller) 5. Re: time-nuts Digest, Vol 101, Issue 152 (Volker Esper) -- Message: 1 Date: Fri, 21 Dec 2012 09:53:51 -0800 From: Said Jacksonsaidj...@aol.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Cc: time-nuts@febo.com time-nuts@febo.com Subject: Re: [time-nuts] time-nuts Digest, Vol 101, Issue 152 Message-ID:6e6305fd-df54-44d5-9ceb-5d4aeb5ae...@aol.com Content-Type: text/plain; charset=us-ascii Mark, Your plot still shows excursions of +/-1E-010, about 100x higher base noise than the Z3801A/Z3805A are capable of achieving. Wonder where that noise is coming from? This noise is probably much higher than the thermal effects. The original post was the question does my Z380xA have reduced stability if I add a fan or similar, I think the answer is shown to be yes. Volker, I wonder if you also see fan-induced spurs in the phase noise from 1Hz to 100Hz. I would not be surprised if the fan vibration adds significant spurs to the 10811A crystal. Bye, Said Sent from my iPad On Dec 21, 2012, at 9:42 AM, Mark Spencermspencer12...@yahoo.ca wrote: This plot should show the frequency change more clearly. (Same data just presented differently.) It seems to me that the noise goes may be going down a bit for a minute or so just after the fan is turned on but I don't believe these plots provide conclusive evidence of this. Regards Mark Spencer Message: 7 Date: Fri, 21 Dec 2012 09:27:29 -0800 From: Said Jacksonsaidj...@aol.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] Z3805A cooling requirements? Message-ID:83ce0384-2996-4155-b51b-9d79910b2...@aol.com Content-Type: text/plain; charset=us-ascii Great plots guys! Looking at these results I think my original claim still holds: ADEV goes up when a fan is involved versus no fan, even on a double oven 10811.. Clearly visible on the 10811, maybe not so much on the MV89 but that unit seems to have frequency moves into the xE-010 region on Marks plot so maybe the effect is just a bit hidden? Bye, Said Sent from my iPad On Dec 21, 2012, at 5:44 AM, Volker Esperail...@t-online.de wrote: ...and the picture of the experiment... The picture enclosed can give you a first impression. What we see is the difference time between the GPS signal and the OCXO (blue) (PPS-TI), which is an HP 10811. In red we can see the EFC. The total span is 24 h. Before I applied the fan, the noise was at a maximum of about +/- 20 ns. Some hours after starting the fan
Re: [time-nuts] time-nuts Digest, Vol 101, Issue 154
Hi Mark, Makes sense, I think the 5370A should be good to 30ps rms or so, so one would think things could be about 2x to 3x better in your plots.. Its hard to get much better without going high-end such as the Miles Timepod etc. Bye, Said Sent From iPhone On Dec 21, 2012, at 11:05, Mark Spencer mspencer12...@yahoo.ca wrote: Said, not sure where the noise is coming from but I suspect it's from the MV89 OCXO itself which was only powered up for 10 hours when the data was collected. The BVA reference and the counter (an HP5370B) have performed significantly better on other occasions. When I have some time over the holidays I'll take another look at this and confirm that the BVA and HP5370B are working as they should. I'll likely compare the BVA to another OCXO using another HP5370B at the same time I'm comparing the BVA to the MV89, then swap the two counters and repeat the measurements, but I didn't have time for that this am (: I saw your request for data re OCXO's and fans and this gave me the incentive to spend a few minutes to power up one of my MV89's, then blow some air over it and collect a bit of data the next morning (: As a side note I've got two Z3805's in service and yes they are great performers over short time intervals (one of them seems to match the short term performance of my BVA on many occasions.) I need to save my pennies for better counter / analyzer as well as the HP5370B is of little use at tau's of less than 100 seconds or so (: Regards Mark S --- On Fri, 12/21/12, time-nuts-requ...@febo.com time-nuts-requ...@febo.com wrote: From: time-nuts-requ...@febo.com time-nuts-requ...@febo.com Subject: time-nuts Digest, Vol 101, Issue 154 To: time-nuts@febo.com Received: Friday, December 21, 2012, 10:23 AM 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-nuts Digest, Vol 101, Issue 152 (Said Jackson) 2. Re: Brooks Shera (Chris Albertson) 3. Re: Z3805A cooling requirements? (Volker Esper) 4. Re: A Day in the Life of Five PPS Sources.. (Tom Miller) 5. Re: time-nuts Digest, Vol 101, Issue 152 (Volker Esper) -- Message: 1 Date: Fri, 21 Dec 2012 09:53:51 -0800 From: Said Jackson saidj...@aol.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Cc: time-nuts@febo.com time-nuts@febo.com Subject: Re: [time-nuts] time-nuts Digest, Vol 101, Issue 152 Message-ID: 6e6305fd-df54-44d5-9ceb-5d4aeb5ae...@aol.com Content-Type: text/plain; charset=us-ascii Mark, Your plot still shows excursions of +/-1E-010, about 100x higher base noise than the Z3801A/Z3805A are capable of achieving. Wonder where that noise is coming from? This noise is probably much higher than the thermal effects. The original post was the question does my Z380xA have reduced stability if I add a fan or similar, I think the answer is shown to be yes. Volker, I wonder if you also see fan-induced spurs in the phase noise from 1Hz to 100Hz. I would not be surprised if the fan vibration adds significant spurs to the 10811A crystal. Bye, Said Sent from my iPad On Dec 21, 2012, at 9:42 AM, Mark Spencer mspencer12...@yahoo.ca wrote: This plot should show the frequency change more clearly. (Same data just presented differently.) It seems to me that the noise goes may be going down a bit for a minute or so just after the fan is turned on but I don't believe these plots provide conclusive evidence of this. Regards Mark Spencer Message: 7 Date: Fri, 21 Dec 2012 09:27:29 -0800 From: Said Jackson saidj...@aol.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] Z3805A cooling requirements? Message-ID: 83ce0384-2996-4155-b51b-9d79910b2...@aol.com Content-Type: text/plain; charset=us-ascii Great plots guys! Looking at these results I think my original claim still holds: ADEV goes up when a fan is involved versus no fan, even on a double oven 10811.. Clearly visible on the 10811, maybe not so much on the MV89 but that unit seems to have frequency moves into the xE-010 region on Marks plot so maybe the effect is just a bit hidden? Bye, Said Sent from my iPad On Dec 21, 2012, at 5:44 AM, Volker Esper ail...@t-online.de wrote: ...and the picture of the
