Re: [time-nuts] Lead acid battery noise levels
The instruments I have used that employed an internal battery supply were meant to run off the batteries only intermittently. But that isn't the case for the OCXO. So the comparison has to be made with trickled charged batteries versus a power supply. But once we get to trickle charging, NiCads are not suitable. That might be why lead acid was used. [I'm thinking of the old Quantum noise measuring gear.] Technically SLA since we are using the batteries indoors around electronic equipment. Incidentally, I favor shunt regulators if noise is the primary concern. They are easier to design with ginormous cap filtering, while LDOs can have issues if the cap ESR is too low. Of course, shunt regulators aren't green. ___ 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] Lead acid battery noise levels
Its just over 10 years since I've used lead acid batteries as the lo noise power option for a low phase noise reference source use in the development of a jitter measurement instrument , we used discrete regs rather than '317s etc, it worked fine but I can't pass on the details. I still have the reference without the batteries which went for recycling long ago, the possible new twist I've not seen noise data on is not batteries but Ultracapacitors intended for regenerative breaking: http://www.maxwell.com/products/ultracapacitors/products/d-cell-series It's nice to try something new and being new might be a way to sidestep environmental concerns. Regards David Message: 7 Date: Thu, 11 Jul 2013 11:48:39 -0600 (MDT) From: Don Lathamd...@montana.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Lead acid battery noise levels Message-ID: 454263ca57f18f7fee4702b190662d3e.squir...@webmail.montana.com Content-Type: text/plain;charset=iso-8859-1 But Hg batteries are So Moot! We're simply not allowed to have them or make them. Nanny won't have them in the house. I have a couple of Accutron clocks that would love to see a mercury cell. ___ 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] Lead acid battery noise levels - super caps
Interesting idea. Capacity equates to about 115mAH (.310WH / 2.7V) and thats to zero output, so not an endurance option. Robert G8RPI From: David t_list_1_o...@braw.co.uk To: time-nuts@febo.com Sent: Thursday, 11 July 2013, 22:17 Subject: Re: [time-nuts] Lead acid battery noise levels Its just over 10 years since I've used lead acid batteries as the lo noise power option for a low phase noise reference source use in the development of a jitter measurement instrument , we used discrete regs rather than '317s etc, it worked fine but I can't pass on the details. I still have the reference without the batteries which went for recycling long ago, the possible new twist I've not seen noise data on is not batteries but Ultracapacitors intended for regenerative breaking: http://www.maxwell.com/products/ultracapacitors/products/d-cell-series It's nice to try something new and being new might be a way to sidestep environmental concerns. Regards David Message: 7 Date: Thu, 11 Jul 2013 11:48:39 -0600 (MDT) From: Don Lathamd...@montana.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Lead acid battery noise levels Message-ID: 454263ca57f18f7fee4702b190662d3e.squir...@webmail.montana.com Content-Type: text/plain;charset=iso-8859-1 But Hg batteries are So Moot! We're simply not allowed to have them or make them. Nanny won't have them in the house. I have a couple of Accutron clocks that would love to see a mercury cell. ___ 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] Lead acid battery noise levels
The thing is, when a SLA is being charged at the float charge voltage range... 13.8V for a 12V SLA, it isn't all that low impedance. Remove the charger, and it will almost instantly drop to 13.2V. At best, the SLA is behaving as a very ugly high ESR electrolytic capacitor. If you want low noise, and drift, you are better off building a good linear supply. -Chuck Harris Gary wrote: The instruments I have used that employed an internal battery supply were meant to run off the batteries only intermittently. But that isn't the case for the OCXO. So the comparison has to be made with trickled charged batteries versus a power supply. But once we get to trickle charging, NiCads are not suitable. That might be why lead acid was used. [I'm thinking of the old Quantum noise measuring gear.] Technically SLA since we are using the batteries indoors around electronic equipment. Incidentally, I favor shunt regulators if noise is the primary concern. They are easier to design with ginormous cap filtering, while LDOs can have issues if the cap ESR is too low. Of course, shunt regulators aren't green. ___ 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] Lead acid battery noise levels
On 11 July 2013 05:47, Mark Spencer mspencer12...@yahoo.ca wrote: Eric: http://tf.nist.gov/general/pdf/1133.pdf discusses the noise levels of various batteries. Regards Mark S Sod's Law comes into play here. From a quick read of that, it seems NiCd are best, but they are being phased out. I was told they were banned in Europe, but I don't know if that is true. I'm pretty sure I've seen NiCd tools in the local DIY store, so I doubt it is true. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of David Kirkby Sent: Thursday, July 11, 2013 10:25 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Lead acid battery noise levels On 11 July 2013 05:47, Mark Spencer mspencer12...@yahoo.ca wrote: Eric: http://tf.nist.gov/general/pdf/1133.pdf discusses the noise levels of various batteries. Regards Mark S Sod's Law comes into play here. From a quick read of that, it seems NiCd are best, but they are being phased out. I was told they were banned in Europe, but I don't know if that is true. I'm pretty sure I've seen NiCd tools in the local DIY store, so I doubt it is true. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
Hi: When Mercury in batteries was banned there was a scramble to eliminate it from Alkaline batteries. Many of the patents you see on a package of Alkaline batteries relate to eliminating Mercury. When the No. 6 dry cell was common the way they were tested was by using a pocket Amp meter to measure what later was called Flash Amps. http://www.prc68.com/I/No6.shtml#Pat Modern Alkaline batteries (actually pretty much all modern batteries) have very low internal resistance, so I would expect them to also have low kTBR type noise. An indication of the low resistance is the Flash Amps current. http://www.prc68.com/I/No6.shtml#FA Here's a table of Flash Amps (and a calculation of internal resistance) for modern batteries (42 milli Ohms): http://www.prc68.com/I/No6.shtml#MFA Typically rechargeable batteries have lower internal resistance than primary batteries, but it might be interesting to measure some of today's primary batteries, like the new 10 year Alkaline cells that have come out in early 2013 or late 2012. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html ___ 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] Lead acid battery noise levels
It's a compromise. NiCds are quiet, but they have to be recharged and can have high self-discharge rates and grow whiskers internally. If I were building a one-off or a few amps, and Hg batteries were plentiful in the stockroom, I might well use them also. In the PAR 113 the NiCd pack has to be replaced pretty often. The unit is either in battery charge or operate mode. They do not 'float charge'. If you get them used, the battery was not even wirth testing. Digi-Key would make up replacements for $100-$150, but that was a while ago. I don't know if you can noise model a battery as an ideal voltage source in series w/ a Thevenin Equivalent, and use the Thevenin resistance in SQR(4KTBR), but it seems at least plausible. This would explain why bigger batteries reported;y have lower noise, at least in part. -John A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike Mike B. Feher, EOZ Inc. 89 Arnold Blvd. Howell, NJ, 07731 732-886-5960 office 908-902-3831 cell -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of David Kirkby Sent: Thursday, July 11, 2013 10:25 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Lead acid battery noise levels On 11 July 2013 05:47, Mark Spencer mspencer12...@yahoo.ca wrote: Eric: http://tf.nist.gov/general/pdf/1133.pdf discusses the noise levels of various batteries. Regards Mark S Sod's Law comes into play here. From a quick read of that, it seems NiCd are best, but they are being phased out. I was told they were banned in Europe, but I don't know if that is true. I'm pretty sure I've seen NiCd tools in the local DIY store, so I doubt it is true. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Lead acid battery noise levels
I'd guess that NiMH cells would be similar to Nicads. Cadmium has been banned in the EU, except where it is essential. The power tool manufacturers successfully negotiated an exemption, so they are still available. I did note that the paper only considered Johnson and shot noise. The very low frequency noise caused by electrochemical / electrolyte movement was not addressed. Robert G8RPI. From: David Kirkby david.kir...@onetel.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thursday, 11 July 2013, 15:25 Subject: Re: [time-nuts] Lead acid battery noise levels On 11 July 2013 05:47, Mark Spencer mspencer12...@yahoo.ca wrote: Eric: http://tf.nist.gov/general/pdf/1133.pdf discusses the noise levels of various batteries. Regards Mark S Sod's Law comes into play here. From a quick read of that, it seems NiCd are best, but they are being phased out. I was told they were banned in Europe, but I don't know if that is true. I'm pretty sure I've seen NiCd tools in the local DIY store, so I doubt it is true. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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] Lead acid battery noise levels
Am 11.07.2013 17:50, schrieb Mike Feher: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. A decent low noise amplifier should feature a nice power supply rejection ratio. For example, the ADA4898 has abt. -100 dB, so the amplifier's own power supply should not be a factor, unless it is _really_ bad. I have built a preamp that averages 10 pairs of ADA4898-2 and I get abt. 200 pV/sqrt Hz, 20/40/60/80 dB gain (plus optional 6 dB boost to make up for 50R-terminations), 0.1 / 10 Hz to 1KHz/120KHz/1 MHz. That works for low source impedance only. Since the design is stable now, I have made a compact layout and will publish it. FR4 is in production currently. It looks like this: https://picasaweb.google.com/103357048842463945642/Tronix?authuser=0feat=directlink The first thing to measure were my lab supplies batteries, of course. There must be huge differences among NiMH. Ansmann 4 * AA 2500mAh were really bad with regard to noise while Sanyo Eneloops approached the limit of the preamp. They seem to be good otherwise, too :-) Unexpectedly, cheap zinc-carbon batteries were at 0.5nV/sqrt Hz, but if I would buy them tomorrow I might get completely different no-name stuff. All measurements up to now are without load. regards, Gerhard ___ 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] Lead acid battery noise levels
Second attempt at emailing again: NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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] Lead acid battery noise levels
But Hg batteries are So Moot! We're simply not allowed to have them or make them. Nanny won't have them in the house. I have a couple of Accutron clocks that would love to see a mercury cell. ed breya Second attempt at emailing again: NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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 Skype: buffler2 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] Lead acid battery noise levels
Third attempt at emailing again: NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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] Lead acid battery noise levels
HI Ed... All three got through; don't know why you are having trouble seeing them. Tom Holmes, N8ZM Tipp City, OH EM79 -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of ed breya Sent: Thursday, July 11, 2013 12:25 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Lead acid battery noise levels NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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] Lead acid battery noise levels
Yeah! In spades. And there really are no good substitutes. I have a number of instruments from ESI, GR and others that are pretty much doorstops w/o them. The solution the camera people use, the silver cells, are not available in the larger sizes for instruments AFAIK. -John === But Hg batteries are So Moot! We're simply not allowed to have them or make them. Nanny won't have them in the house. I have a couple of Accutron clocks that would love to see a mercury cell. ed breya Second attempt at emailing again: NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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 Skype: buffler2 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 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] Lead acid battery noise levels
I have an old Keithley 602 meter that uses a single Hg cell for the ohm meter function. There are not many alternatives that matched the stability of the mercury cells. I don't see why they could not just put a core charge on the cells that would make it desirable to recycle them. Or require a trade in to get a new battery. I also have an ultrasonic corona detector that used a multi cell battery (8.4 volts) that I can't get any more. Regards, Tom - Original Message - From: J. Forster j...@quikus.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thursday, July 11, 2013 2:15 PM Subject: Re: [time-nuts] Lead acid battery noise levels Yeah! In spades. And there really are no good substitutes. I have a number of instruments from ESI, GR and others that are pretty much doorstops w/o them. The solution the camera people use, the silver cells, are not available in the larger sizes for instruments AFAIK. -John === But Hg batteries are So Moot! We're simply not allowed to have them or make them. Nanny won't have them in the house. I have a couple of Accutron clocks that would love to see a mercury cell. ed breya Second attempt at emailing again: NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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 Skype: buffler2 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 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] Lead acid battery noise levels
Ed. I for one am getting all of your messages. Perhaps your spam filter is taking them out for some reason. Regards. Max. K 4 O DS. Email: m...@maxsmusicplace.com Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Woodworking site http://www.angelfire.com/electronic/funwithtubes/Woodworking/wwindex.html Music site: http://www.maxsmusicplace.com To subscribe to the fun with transistors group send an email to. funwithtransistors-subscr...@yahoogroups.com To subscribe to the fun with tubes group send an email to, funwithtubes-subscr...@yahoogroups.com To subscribe to the fun with wood group send a blank email to funwithwood-subscr...@yahoogroups.com - Original Message - From: ed breya e...@telight.com To: time-nuts@febo.com Sent: Thursday, July 11, 2013 11:39 AM Subject: Re: [time-nuts] Lead acid battery noise levels Third attempt at emailing again: NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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] Lead acid battery noise levels
Hi Ok, let's put some numbers on this: 1) The original post was about an OCXO (as opposed to a VCXO or VCO). 2) One would *assume* that only stable OCXO's are of interest to this group… :)…. 3) Single ovens with 1x10^-9 per percent delta V are not so stable, parts with 1x10^-11 per percent are quite possible. 4) Supply voltages around 12 volts are pretty common 5) 1.0x10^-13 at one second is doing pretty good on an OCXO From that one can do some math. One percent of 12 volts is 120 mv. One mv will be 1.0x10^-11 on the not so stable OCXO and 1.0X10^-14 on the stable one. Is your supply good to 1 mv? Most of my lab supplies are. If so, that's probably good enough. If you have a poor supply, many common 3 terminal regulators are amazingly stable under normal lab conditions. I *know* that my batteries aren't stable to 1 mv over days with an OCXO pulling current off of them. Regulator changes voltage with temperature? So do batteries and OCXO's and lab supplies. Bob On Jul 11, 2013, at 3:39 PM, Max Robinson m...@maxsmusicplace.com wrote: Ed. I for one am getting all of your messages. Perhaps your spam filter is taking them out for some reason. Regards. Max. K 4 O DS. Email: m...@maxsmusicplace.com Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Woodworking site http://www.angelfire.com/electronic/funwithtubes/Woodworking/wwindex.html Music site: http://www.maxsmusicplace.com To subscribe to the fun with transistors group send an email to. funwithtransistors-subscr...@yahoogroups.com To subscribe to the fun with tubes group send an email to, funwithtubes-subscr...@yahoogroups.com To subscribe to the fun with wood group send a blank email to funwithwood-subscr...@yahoogroups.com - Original Message - From: ed breya e...@telight.com To: time-nuts@febo.com Sent: Thursday, July 11, 2013 11:39 AM Subject: Re: [time-nuts] Lead acid battery noise levels Third attempt at emailing again: NiCd batteries should have the lowest noise for their size due to low resistance, but if you look at ever-lower frequency, the Hg should be superior since it has the most stable voltage with time and temperature. Drift (including self-discharge) and temperature variation response can appear as very low frequency noise independent of the other noise sources and operating conditions. Hg batteries are so stable that they were commonly used as voltage references or to power small circuits without any additional regulation needed. Ed Mike Feher wrote: A long time ago, when I was concerned about a phase noise issue, I found an old NBS article. It was on measuring phase noise and included a schematic of an ultra-low noise amplifier. In that amplifier they used Mercury batteries. I also glanced at the referenced article, stating NiCad is the lowest noise, and, NiCads were available for a long time, yet they used Mercury. Regards - Mike ___ 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] Lead acid battery noise levels
a...@bardagjy.com said: The SRS 560 and 570, low noise voltage and current preamplifiers respectively, both use bog standard sealed lead acid batteries. Is that to reduce power supply noise or to get a clean ground that isn't connected to wall power? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
I wonder if lithium batteries would have a good noise figure. The nano-structure of the electrodes give them very large surface area and low resistance, but the charge carriers are different than other types of chemistry and I don't know if that's good or bad. On Wed, Jul 10, 2013 at 9:01 AM, Hal Murray hmur...@megapathdsl.net wrote: a...@bardagjy.com said: The SRS 560 and 570, low noise voltage and current preamplifiers respectively, both use bog standard sealed lead acid batteries. Is that to reduce power supply noise or to get a clean ground that isn't connected to wall power? -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
Eric: http://tf.nist.gov/general/pdf/1133.pdf discusses the noise levels of various batteries. Regards Mark S Message: 6 Date: Wed, 10 Jul 2013 11:11:00 -0700 From: Eric Williams wd6...@gmail.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Lead acid battery noise levels Message-ID: cafagtrqveohikn4op01myvn6vkdk+bdlsjpwyjrrmxp0sdd...@mail.gmail.com Content-Type: text/plain; charset=ISO-8859-1 I wonder if lithium batteries would have a good noise figure. The nano-structure of the electrodes give them very large surface area and low resistance, but the charge carriers are different than other types of chemistry and I don't know if that's good or bad. ___ 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] Lead acid battery noise levels
In message 0ef755ef-06b6-4543-b0a5-24517d471...@yahoo.ca, Mark Spencer writes : Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ? I did some research too, including asking a bloke who does lead-acid for nuclear reactors for a living. If you want your batteries to last, the elctrolyte has to move, otherwise you get stratification with higher density at the bottom, lower density at the top, and the plates over- and under-charged at the same time. The noise you get is pretty LF, but it can be quite a few mV and it is asymmetric, in that positive slopes are generally steeper than negative slopes. Gelled and glass-mat batteries have higher noise-amplitude but lower frequency than liquid lead-acid batteries, because the mechanical resistance to electrolyte movement is much higher, so it tends to happen in burps whereas a liquid lead-acid allows the electrolyte to flow (almost) freely. So the recommended configuraiton for low-noise is a liquid lead-acid (OPzS) which is float-charged in the high end of the voltage range recommended by the manufacturer. This gives most electrolysis and therefore most electrolyte movement and need for water replenishment. It also means gaseous hydrogen, which requires ventilation. I havn't done any experiments to verify this. I did find some comments on an audiophile forum that indicated that gel cell batteries are not known for low noise levels (: Don't even think about advice from audiohomoeøpathicists, the 99.9% which isn't downright bullshit is incorrect. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] Lead acid battery noise levels
On 9 July 2013 04:52, Mark Spencer mspencer12...@yahoo.ca wrote: Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ? Have you come across the volt-nuts list? https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts I see a bizzare review of an HP 3457A meter on utube http://www.youtube.com/watch?v=HfxpJCdgVwc where the guy determines the noise level of the 6.5/7.5 digit meter by measuring the voltage of what he describes as a general purpose lab power supply. Is it me, or is it a bit dumb to try to measure the noise level of a laboratory multimeter by using a general purpose lab power supply. I must admit, I thought that using a battery would have been stable at least short term, but it seems there is noise on a battery - something I was not aware of until today. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
David Kirkby wrote: On 9 July 2013 04:52, Mark Spencermspencer12...@yahoo.ca wrote: Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ? Have you come across the volt-nuts list? https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts I see a bizzare review of an HP 3457A meter on utube http://www.youtube.com/watch?v=HfxpJCdgVwc where the guy determines the noise level of the 6.5/7.5 digit meter by measuring the voltage of what he describes as a general purpose lab power supply. Is it me, or is it a bit dumb to try to measure the noise level of a laboratory multimeter by using a general purpose lab power supply. I must admit, I thought that using a battery would have been stable at least short term, but it seems there is noise on a battery - something I was not aware of until today. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. A battery is noisest when current is flowing in the battery. With no current flow (or electrolyte disturbance) the noise is very low. NIST has measured the noise of unloaded NiCd cells for example and it is extremely low. Bruce ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
EGG Princeton Applied Research made a very low noise preamp unit, the 113, which was pretty much the industry leader for years. It was often used with Lock-In amplifiers. The unit used NiCds, I believe for that, among other, reasons. I'd expect Ithaco and SAE have similar products. -John === David Kirkby wrote: On 9 July 2013 04:52, Mark Spencermspencer12...@yahoo.ca wrote: Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ? Have you come across the volt-nuts list? https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts I see a bizzare review of an HP 3457A meter on utube http://www.youtube.com/watch?v=HfxpJCdgVwc where the guy determines the noise level of the 6.5/7.5 digit meter by measuring the voltage of what he describes as a general purpose lab power supply. Is it me, or is it a bit dumb to try to measure the noise level of a laboratory multimeter by using a general purpose lab power supply. I must admit, I thought that using a battery would have been stable at least short term, but it seems there is noise on a battery - something I was not aware of until today. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. A battery is noisest when current is flowing in the battery. With no current flow (or electrolyte disturbance) the noise is very low. NIST has measured the noise of unloaded NiCd cells for example and it is extremely low. Bruce ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Lead acid battery noise levels
The SRS 560 and 570, low noise voltage and current preamplifiers respectively, both use bog standard sealed lead acid batteries. Andy Bardagjy bardagjy.com On Tue, Jul 9, 2013 at 9:26 AM, J. Forster j...@quikus.com wrote: EGG Princeton Applied Research made a very low noise preamp unit, the 113, which was pretty much the industry leader for years. It was often used with Lock-In amplifiers. The unit used NiCds, I believe for that, among other, reasons. I'd expect Ithaco and SAE have similar products. -John === David Kirkby wrote: On 9 July 2013 04:52, Mark Spencermspencer12...@yahoo.ca wrote: Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ? Have you come across the volt-nuts list? https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts I see a bizzare review of an HP 3457A meter on utube http://www.youtube.com/watch?v=HfxpJCdgVwc where the guy determines the noise level of the 6.5/7.5 digit meter by measuring the voltage of what he describes as a general purpose lab power supply. Is it me, or is it a bit dumb to try to measure the noise level of a laboratory multimeter by using a general purpose lab power supply. I must admit, I thought that using a battery would have been stable at least short term, but it seems there is noise on a battery - something I was not aware of until today. Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. A battery is noisest when current is flowing in the battery. With no current flow (or electrolyte disturbance) the noise is very low. NIST has measured the noise of unloaded NiCd cells for example and it is extremely low. Bruce ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ 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] Lead acid battery noise levels
Thanks all for the responses so far. Just to clarify I am not charging the batteries while using them to power the OCXO. With a load of less than 150 mA and a nominal capacity of 100 AH I don't foresee any issues running the OCXO for a week or so (: I periodically charge the batteries from time to time and probably should discharge a bit more frequently anyways (they serve as a backup power source for some other time nuts gear.) Unfortunately the OCXO in question is only spec'd to handle a power source of 24 volts plus or minus 10% which rules out simply leaving the OCXO directly connected to the battery bank while the batteries are float charged. Best regards Mark Spencer ___ 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] Lead acid battery noise levels
Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ? I recently discovered the HP bench supply I've been powering one of my OCXO's from is slightly affected by AC line transients, so I've been running one of my OCXO's from a bank of 100 amp hour gelled lead acid batteries. Apart from the lack of glitches due to line transients, the performance of the OCXO appears to be better. Before I embark on a quest for a very low noise power supply (or contemplate building one) I'd be curious in knowing roughly what the typical noise specs for the batteries are. I did find some comments on an audiophile forum that indicated that gel cell batteries are not known for low noise levels (: Best regards Mark Spencer ___ 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] Lead acid battery noise levels
I did read about this once but with smaller batteries. I think the noise is mostly equal the internal resistance of the battery. So an AA cell might be noisy but a 100AH might have a lot less internal resistance. I have this page bookmarked. My application is audio recording studio equipment, they car a lot about noise too. regulators_noise4_e.htmlhttp://www.tnt-audio.com/clinica/regulators_noise4_e.html On Mon, Jul 8, 2013 at 8:52 PM, Mark Spencer mspencer12...@yahoo.ca wrote: Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ? I recently discovered the HP bench supply I've been powering one of my OCXO's from is slightly affected by AC line transients, so I've been running one of my OCXO's from a bank of 100 amp hour gelled lead acid batteries. Apart from the lack of glitches due to line transients, the performance of the OCXO appears to be better. Before I embark on a quest for a very low noise power supply (or contemplate building one) I'd be curious in knowing roughly what the typical noise specs for the batteries are. I did find some comments on an audiophile forum that indicated that gel cell batteries are not known for low noise levels (: Best regards Mark Spencer ___ 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.
