Question... do the old circuits get better with age? It would seem that the old standards would be much better now than they were when new. Is there any rule of thumb? Does a 20ppm/year circuit become a 10ppm/year circuit in say, 20 years? The industry uses voltage and temperature to simulate aging... so just 'aging' itself should work! The old survivors from the 70s, 80s and 90s should be very good! Willy ----- Original Message ----- From: <volt-nuts-request@febo.com> To: <volt-nuts@febo.com> Sent: Monday, March 10, 2014 8:41 AM Subject: volt-nuts Digest, Vol 55, Issue 11 > Send volt-nuts mailing list submissions to > volt-nuts@febo.com > > To subscribe or unsubscribe via the World Wide Web, visit > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > or, via email, send a message with subject or body 'help' to > volt-nuts-request@febo.com > > You can reach the person managing the list at > volt-nuts-owner@febo.com > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of volt-nuts digest..." > > > Today's Topics: > > 1. Re: Batch of old reference zeners (Bob Albert) > 2. fluke 332d (Ken Goodhew) > 3. Re: fluke 332d (J. L. Trantham) > 4. Re: Batch of old reference zeners (Andreas Jahn) > 5. Re: Batch of old reference zeners (M K) > 6. Re: Batch of old reference zeners (Dr. David Kirkby) > 7. Re: A Fluke 732A (Charles Steinmetz) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Sun, 9 Mar 2014 17:35:29 -0700 (PDT) > From: Bob Albert <bob91343@yahoo.com> > To: Discussion of precise voltage measurement <volt-nuts@febo.com> > Subject: Re: [volt-nuts] Batch of old reference zeners > Message-ID: > <1394411729.27034.YahooMailNeo@web122605.mail.ne1.yahoo.com> > Content-Type: text/plain; charset=iso-8859-1 > > I have a 3456A.? Is that good enough? > > > Bob > > > > > On Sunday, March 9, 2014 4:41 PM, Jan Fredriksson <jan@41hz.com> wrote: > > I have a batch of voltage references ICs on the shelf, several thousand of > each type. They all have date codes of around 1983, ie 30 years old. It > would be great to have some drift data on them. > > The ones listed below are the best of the bunch. > > - AS431, TO-92 and SOIC-8, 20ppm/C 120nV/sqrtHz (0.5% or 0.1%?) > > - LM385Z, TO-92, 80ppm/C, 600nV/SqrtHz, 60uV, 20ppm/SqrtKhr > > - LM329CZ, TO-92, 75nV/sqrtHz, 30ppm/C 7uV noise 20ppm (8ppm?) /SqrtKhr. > - AS2951/2954, SOIC-8, 20ppm/C > > I am willing to send a handful (like at least 50 pcs) to anyone who can > set > up and monitor the drift of them for a few months and send me some data. > > Any takers? > > I will do similar monitoring myself, but would appreciate data from > others, > that's why I am doing this. > > I am also building some other references to compare with, based on LTZ1000 > and other zeners. > > I am not asking anything in return, except that you return drift data, > measured with some decent method, ie single digit ppm stability. > If you happen to have some resistors rated like 10ppm/C or lower, surface > or hole mount, I'd appreciate some of those in return, in values 1K-10K, > but that is not a requirement. > > Jan > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. > > ------------------------------ > > Message: 2 > Date: Mon, 10 Mar 2014 12:06:26 +1100 > From: "Ken Goodhew" <kgoodhew@iinet.net.au> > To: <volt-nuts@febo.com> > Subject: [volt-nuts] fluke 332d > Message-ID: <000f01cf3bfc$f68da8b0$e3a8fa10$@iinet.net.au> > Content-Type: text/plain; charset="us-ascii" > > Just after the groups collective opinion on the suitability of a fluke > 332d > as a voltage standard for a home lab. > > > > --- > This email is free from viruses and malware because avast! Antivirus > protection is active. > http://www.avast.com > > > ------------------------------ > > Message: 3 > Date: Sun, 9 Mar 2014 21:34:27 -0500 > From: "J. L. Trantham" <jltran@att.net> > To: "'Discussion of precise voltage measurement'" <volt-nuts@febo.com> > Subject: Re: [volt-nuts] fluke 332d > Message-ID: <00a601cf3c09$42ee00e0$c8ca02a0$@att.net> > Content-Type: text/plain; charset="us-ascii" > > Ken, > > I think the 332D would be a good tool for calibration of DMM's, etc., but > probably a bit of an energy hog to leave turned on all the time. > > What do you want to do? > > For a constantly on 10 VDC reference, I would consider a 731B or 732A. > For > a 'calibrator', the 332D would be a good DC voltage calibrator up to 1100 > VDC, IIRC. If you also need AC voltage, current, and resistance, consider > a > Fluke 5100B. For separate units, consider a 5200 for AC voltage and 5450 > or > some individual standard resistors for resistance. If you want only DC > voltage and more stability than the 332D, consider a 5440B. > > Careful, this stuff can be addicting. > > Good luck. > > Joe > > -----Original Message----- > From: volt-nuts-bounces@febo.com [mailto:volt-nuts-bounces@febo.com] On > Behalf Of Ken Goodhew > Sent: Sunday, March 09, 2014 8:06 PM > To: volt-nuts@febo.com > Subject: [volt-nuts] fluke 332d > > Just after the groups collective opinion on the suitability of a fluke > 332d > as a voltage standard for a home lab. > > > > --- > This email is free from viruses and malware because avast! Antivirus > protection is active. > http://www.avast.com > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there. > > > > ------------------------------ > > Message: 4 > Date: Mon, 10 Mar 2014 08:12:21 +0100 > From: Andreas Jahn <Andreas_-_Jahn@t-online.de> > To: volt-nuts@febo.com > Subject: Re: [volt-nuts] Batch of old reference zeners > Message-ID: <531D65D5.8040504@t-online.de> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Hello Bob, > > the instrument will be your least worries. > with 20-80ppm/K you will need a very well stabilized (<0.1K) temperature > environment for the references. > Otherwise you will not detect ageing but the temperature of your > environment. > > A volt nut would only use the LM329 from the list (buried zener). > The others are bandgap references with much larger ageing drift. > But to detect ageing after some 100 hrs you will need a well stabilized > current source (< 0.1% drift during setup) > or a even better voltage source (<0.05% over temperature and ageing) and > a rather stable resistor for each reference in the setup. > > If you use sockets for the references their drift will outperform the > reference drift if the board is handled (e.g. for measuring) > so you will need to have a (relay-) multiplexer for your instrument. > If you solder the references to a board you will create stress to the > device and this will give a large initial drift after soldering. > > with best regards > > Andreas > > > Am 10.03.2014 01:35, schrieb Bob Albert: >> I have a 3456A. Is that good enough? >> >> >> Bob >> >> >> >> >> On Sunday, March 9, 2014 4:41 PM, Jan Fredriksson <jan@41hz.com> wrote: >> >> I have a batch of voltage references ICs on the shelf, several thousand >> of >> each type. They all have date codes of around 1983, ie 30 years old. It >> would be great to have some drift data on them. >> >> The ones listed below are the best of the bunch. >> >> - AS431, TO-92 and SOIC-8, 20ppm/C 120nV/sqrtHz (0.5% or 0.1%?) >> >> - LM385Z, TO-92, 80ppm/C, 600nV/SqrtHz, 60uV, 20ppm/SqrtKhr >> >> - LM329CZ, TO-92, 75nV/sqrtHz, 30ppm/C 7uV noise 20ppm (8ppm?) /SqrtKhr. >> - AS2951/2954, SOIC-8, 20ppm/C >> >> I am willing to send a handful (like at least 50 pcs) to anyone who can >> set >> up and monitor the drift of them for a few months and send me some data. >> >> Any takers? >> >> I will do similar monitoring myself, but would appreciate data from >> others, >> that's why I am doing this. >> >> I am also building some other references to compare with, based on >> LTZ1000 >> and other zeners. >> >> I am not asking anything in return, except that you return drift data, >> measured with some decent method, ie single digit ppm stability. >> If you happen to have some resistors rated like 10ppm/C or lower, surface >> or hole mount, I'd appreciate some of those in return, in values 1K-10K, >> but that is not a requirement. >> >> Jan >> _______________________________________________ >> volt-nuts mailing list -- volt-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >> and follow the instructions there. >> _______________________________________________ >> volt-nuts mailing list -- volt-nuts@febo.com >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >> and follow the instructions there. > > > > ------------------------------ > > Message: 5 > Date: Mon, 10 Mar 2014 08:00:12 +0000 > From: M K <m1k3k1@hotmail.com> > To: volt-nuts@febo.com > Subject: Re: [volt-nuts] Batch of old reference zeners > Message-ID: <BLU0-SMTP1471DF4E569F0C192ACA44691740@phx.gbl> > Content-Type: text/plain; charset="ISO-8859-1"; format=flowed > > Hi, > > I have an 8.5 digit wavetek, and a bunch of Solartron and wavetek 7.5 > digit meters, but it seems to me that doing justice to the 329 > references is going to need stable wirewound or foil resistors, and a > few months will be only just long enough. > > MK > > On 10/03/2014 07:12, Andreas Jahn wrote: >> Hello Bob, >> >> the instrument will be your least worries. >> with 20-80ppm/K you will need a very well stabilized (<0.1K) >> temperature environment for the references. >> Otherwise you will not detect ageing but the temperature of your >> environment. >> >> A volt nut would only use the LM329 from the list (buried zener). >> The others are bandgap references with much larger ageing drift. >> But to detect ageing after some 100 hrs you will need a well >> stabilized current source (< 0.1% drift during setup) >> or a even better voltage source (<0.05% over temperature and ageing) >> and a rather stable resistor for each reference in the setup. >> >> If you use sockets for the references their drift will outperform the >> reference drift if the board is handled (e.g. for measuring) >> so you will need to have a (relay-) multiplexer for your instrument. >> If you solder the references to a board you will create stress to the >> device and this will give a large initial drift after soldering. >> >> with best regards >> >> Andreas >> >> >> Am 10.03.2014 01:35, schrieb Bob Albert: >>> I have a 3456A. Is that good enough? >>> >>> >>> Bob >>> >>> >>> >>> >>> On Sunday, March 9, 2014 4:41 PM, Jan Fredriksson <jan@41hz.com> wrote: >>> I have a batch of voltage references ICs on the shelf, several >>> thousand of >>> each type. They all have date codes of around 1983, ie 30 years old. It >>> would be great to have some drift data on them. >>> >>> The ones listed below are the best of the bunch. >>> >>> - AS431, TO-92 and SOIC-8, 20ppm/C 120nV/sqrtHz (0.5% or 0.1%?) >>> >>> - LM385Z, TO-92, 80ppm/C, 600nV/SqrtHz, 60uV, 20ppm/SqrtKhr >>> >>> - LM329CZ, TO-92, 75nV/sqrtHz, 30ppm/C 7uV noise 20ppm (8ppm?) /SqrtKhr. >>> - AS2951/2954, SOIC-8, 20ppm/C >>> >>> I am willing to send a handful (like at least 50 pcs) to anyone who >>> can set >>> up and monitor the drift of them for a few months and send me some data. >>> >>> Any takers? >>> >>> I will do similar monitoring myself, but would appreciate data from >>> others, >>> that's why I am doing this. >>> >>> I am also building some other references to compare with, based on >>> LTZ1000 >>> and other zeners. >>> >>> I am not asking anything in return, except that you return drift data, >>> measured with some decent method, ie single digit ppm stability. >>> If you happen to have some resistors rated like 10ppm/C or lower, >>> surface >>> or hole mount, I'd appreciate some of those in return, in values 1K-10K, >>> but that is not a requirement. >>> >>> Jan >>> _______________________________________________ > > > > ------------------------------ > > Message: 6 > Date: Mon, 10 Mar 2014 08:57:52 +0000 > From: "Dr. David Kirkby" <drkirkby@gmail.com> > To: Discussion of precise voltage measurement <volt-nuts@febo.com> > Subject: Re: [volt-nuts] Batch of old reference zeners > Message-ID: > <CANX10hA0RLst9fD8zknuL_oOkxZ48ukQyEJDTR0BFjUG_f5-=g@mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > On 9 Mar 2014 23:39, "Jan Fredriksson" <jan@41hz.com> wrote: >> >> I have a batch of voltage references ICs on the shelf, several thousand >> of >> each type. They all have date codes of around 1983, ie 30 years old. It >> would be great to have some drift data on them. > > Since you have so many, it would be interesting if you built up some > references, measured their stability, then shipped a random sample around > the world - perhaps to two or three time-nuts on different continents. > Then > see if the transport actually has any effect on them. > > The discussions about the Fluke being shipped powered up made me think of > this one. > > Of course shipping them powered up could be an additional interesting > experiment, but as I wrote before, there are issues with that, although > perhaps if the current consumption was low enough, the size of the battery > needed would be incredibly small, and one could probably chose a type for > which there is no strict regulations about carrying them. > > Dave > > > ------------------------------ > > Message: 7 > Date: Mon, 10 Mar 2014 08:38:15 -0400 > From: Charles Steinmetz <csteinmetz@yandex.com> > To: Discussion of precise voltage measurement <volt-nuts@febo.com> > Subject: Re: [volt-nuts] A Fluke 732A > Message-ID: <20140310163935.dZ7WbDfm@smtp16.mail.yandex.net> > Content-Type: text/plain; charset="us-ascii"; format=flowed > > Thomas wrote: > >>If I send a 732A to Fluke and have it calibrated, and you stop by >>with yours shortly after mine returns, has a day or so to settle, >>and appear correct with my 3458A, you could then calibrate your 732A >>using of mine and feel fairly confident you standard is also a few >>PPM from 10 volts. Now lets stay you repeat this with another >>Volt-Nut when his standard returns. You do not have documents >>proving the accuracy of your standard because none of the standards >>used are parts of a accredited lab, > > Documentation and accreditation are two entirely different > things. In this case, the documentation would be the informal, "on > [date] I compared and adjusted this standard to Thomas's 732A that > was just back from calibration and sanity-checked with a 3458A, using > a [Fluke 845A null meter, or whatever]." Knowing the published > uncertainties of the 732A, I can even calculate the uncertainty of my > 732A as of the moment of calibration, and at intervals thereafter > based on the published uncertainties. > > Checking against another recently-calibrated 732A at a later date can > confirm or deny that mine remains within the published uncertainty at > that time. If it does, that fact becomes part of my (informal) > documentation. If it doesn't, the presumption is that one of the > 732As is broken. We can suspect that it is mine, but we cannot know > that without further testing. > > Best regards, > > Charles > > > > > > ------------------------------ > > _______________________________________________ > volt-nuts mailing list > volt-nuts@febo.com > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > > End of volt-nuts Digest, Vol 55, Issue 11 > *****************************************

Aging is beneficial because it allows a part to physically relax into a shape that is appropriate for the way it is being operated... So, if a zener is going to be operated with no bias current, and at room temperature, sitting on a shelf for 30 years might be a plus... But not so much if the part is going to be run at 5ma bias, and a 55C operating temp. In that case, aging begins when the part is up to temperature, and power is turned on. -Chuck Harris new wrote: > Question... do the old circuits get better with age? > > It would seem that the old standards would be > much better now than they were when new. > > Is there any rule of thumb? Does a 20ppm/year > circuit become a 10ppm/year circuit in say, 20 years? > > The industry uses voltage and temperature to simulate > aging... so just 'aging' itself should work! The old > survivors from the 70s, 80s and 90s should be very good! > > Willy