Re: [volt-nuts] Wanted - UK source of a replacement battery (type LX 1634) for HP 3457A 6.5 digit multimeter

On 25 Jan 2016 03:51, "Tom Miller" wrote: > > Looking through the service manual I don't see a connection from the battery to the NVRAM. I am sure I measured battery voltage on pin28 so I suspect a schematic error. Can someone that has one open verify that? My 3457 is in cal and I prefer not to br

[volt-nuts] Fall of SRAM voltage in a 3457A without external power

topped the voltage up from the mains just before removing it from the chassis. Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company number 08914892. http://www.kirkbymicrowave.

Re: [volt-nuts] Fall of SRAM voltage in a 3457A without external power

On 25 January 2016 at 11:50, Poul-Henning Kamp wrote: > > In message < > canx10hcamahhhxqiao9bdzu03c2bbt787mr10rmnywk3oa8...@mail.gmail.com> > , "Dr. David Kirkby (Kirkby Microwave Ltd)" writes: > > >ESD and leakage of the human body would probabl

[volt-nuts] 3457A - should I preserve SRAM contents, or purposely corrupt them by removing power?

bly correct for that, if it is drifting in one direction. Thoughts? Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company number 08914892. http://www.kirkbymicrowave.co.uk/ Tel: 07910

Re: [volt-nuts] 3457A - should I preserve SRAM contents, or purposely corrupt them by removing power?

On 25 January 2016 at 15:40, Poul-Henning Kamp wrote: > > In message < > canx10halwjxt+8ev8lywdqy9eez+anawihgqeyrzntsy80v...@mail.gmail.com> > , "Dr. David Kirkby (Kirkby Microwave Ltd)" writes: > > >I'm wondering if I would be better purpos

Re: [volt-nuts] Wanted - UK source of a replacement battery (type LX 1634) for HP 3457A 6.5 digit multimeter

On 25 January 2016 at 15:23, Andrea Baldoni wrote: > On Sun, Jan 24, 2016 at 07:54:34PM +0000, Dr. David Kirkby (Kirkby > Microwave Ltd) wrote: > > > I've got a HP 3457A 6.5 digit multimeter - S/N 2703A04579. It's working > > fine, but I'm aware the battery

Re: [volt-nuts] 3457A - should I preserve SRAM contents, or purposely corrupt them by removing power?

On 25 January 2016 at 11:12, Dr. David Kirkby (Kirkby Microwave Ltd) < drkir...@kirkbymicrowave.co.uk> wrote: > As noted in another thread, I want to replace a battery in a 3457A that > has not been replaced in at least 11 years. The instrument has not been > calibrated in that

Re: [volt-nuts] volt-nuts Digest, Vol 77, Issue 15

UOn 31 Jan 2016 19:56, "new" wrote: > > I'm thinking of doing non-commercial 'calibrations' for > folks like us volt-nuts. > > Since I have three 3458s, three 732As, a 732b, a 4214, > an sr104, a 4210, all NIST cal'ed and I could do front-panel > adjustments for the 3457. > Probably best to d

Re: [volt-nuts] Just back from cal

On 8 Apr 2016 04:21, "Joseph Gray" wrote: > > In February, I sent my HP 3457A in for cal. In late March, I sent my > EDC VS330 DC Voltage Reference in for cal. Today, I just got the VS330 > back and thought I'd compare the two instruments. Did you send them to the manufacturers or a third party l

[volt-nuts] Suggestions for 10 milli Ohm 0.04 % 100 W resistor

I have an HP 6674A power supply with option J06, which means that the PSU is 70 V @ 30 A rather than the standard 60 V @ 35 A . I've replaced a couple of bits in this and will need to replace some more, so it would be prudent to get this calibrated. The service manual calls for a 8.5 digit 3458A

Re: [volt-nuts] LTZ1000 project build

On 25 May 2016 at 19:24, Russ Ramirez wrote: > A lot of great information Eric, thanks for sharing the link. > > Due to my ignorance in general on the subject of Metrology, I have the > following question for the list. > > If one built a project with the LTZ1000, like the one described on xDevs >

Re: [volt-nuts] LTZ1000 project build

On 4 Jun 2016 20:44, "Poul-Henning Kamp" wrote: > > > In message <57527f8a.6070...@yandex.com>, Charles Steinmetz writes: > > >As I have mentioned before, for many years I have put precision circuits > >that may be sensitive to humidity into gasketed metal boxes with fresh > >silica gel p

[volt-nuts] Keithley 2001 vs HP 3457A multimeters / Any problems to watch out for on Keithley 2001?

I've got an HP 3457A (6.5 digit multimeter) which has served me well. But I see a Keithley 2001 7.5 digit meter on eBay http://www.ebay.co.uk/itm/152113460174 which sort of tempted me as 1) It has an extra digit, I have not looked to see how much that extra digit gains one. It would be nice to

[volt-nuts] Keithley 2001 - do you need to open it to calibrate it?

I got the 2001 that I ordered yesterday. There are a few things that make me feel uneasy about it, so I will probably return it. The calibration seal is missing off the front, which is obvious from the eBay photo, but also one at the bottom which looks as though one needs to open in order to get i

Re: [volt-nuts] Thermal EMF of common solder

On 26 June 2016 at 15:12, Andrea Baldoni wrote: > Hello All. > > I measured the thermal EMF of two common solder, the lead free > Sn96.5/Ag3/Cu0.5 and the old Sn60/Pb40. > Please excuse my ignorance, but how do you mean the thermal EMF of solder? Do you not need another metal, such as copper to

Re: [volt-nuts] Keithley 2001 - do you need to open it to calibrate it?

On 26 June 2016 at 20:46, Todd Micallef wrote: > David, > > I have found that many sellers like to remove any calibration stickers or > tamper evident stickers. Not sure why they do that as a sticker does not > mean the item is calibrated. > The sticker on the front has been removed, but the one

[volt-nuts] Keysight 3458A vs Keithley 2002 8.5 digit multimeters.

I am interested to hear people's view on the relative merits of the HP/Agilent/ Keysight 3458A vs the Keithley 2002. I noticed that when I recently visit the standard lab for voltage at NPL, the place was littered with Agilent 3458As, but I did not notice a single Keithley 2002. But maybe NPL get

Re: [volt-nuts] Keysight 3458A vs Keithley 2002 8.5 digit multimeters.

On 18 Jul 2016 17:34, "John Phillips" wrote: > > Most labs never turn 3458As off. The longer they are on the lower the drift > rate. I would rather have an 20 year old meter with new batteries than a > new meter. If one buys a used meter, one has no idea if it has been switched on very occasional

[volt-nuts] Calibration of 34401A

I have a 'friend" (actually a person who I have never met, but is a pain in the ***). He sold a Agilent 34401A multimeter which the customer said is out of specification and can not be adjusted. Quickly scanning the measurent results, the meter is not showing results with any huge errors (say

Re: [volt-nuts] Calibration of 34401A

On 12 Oct 2016 10:31, "Poul-Henning Kamp" wrote: > > > In message <120112818.2234439.1476263954...@mail.yahoo.com>, Bruce Griffiths wr > ites: > > >Does anybody know if a 34401A can be adjusted by a competent 3rd party lab, > >or are the details of how to adjust the meter not available ou

Re: [volt-nuts] Low-cost Josephson Junction Array

On 19 October 2016 at 20:15, Ken Peek wrote: > Well, I already have a 3458A, OK, quite an expensive multimeter. Otuside my budget for something I don't really need, but would like! $400K is *WAY* out of my budget. I was looking more for > something on the surplus market-- or some "cast awa

[volt-nuts] Is there a "standard" much better than a LTZ1000, but much cheaper than a Josephson Junction Array?

The question about the Josephson Junction Array got me thinking. I wonder if there are any sort of technologies that can produce a voltage with much better stability than the LTZ1000, but without the cost of a Josephson Junction Array. A sort of half-way house. BTW, I see some rather battered up L

Re: [volt-nuts] Is there a "standard" much better than a LTZ1000, but much cheaper than a Josephson Junction Array?

On 20 October 2016 at 00:08, Poul-Henning Kamp wrote: > > In message g...@mail.gmail.com> > , "Dr. David Kirkby (Kirkby Microwave Ltd)" writes: > > >The question about the Josephson Junction Array got me thinking. I wonder > >if there are any so

Re: [volt-nuts] low emf solder

On 28 Oct 2016 15:25, "Juris L" wrote: > > Found reference to optimal emf solder composition cadmium/tin alloy > (70 %/30 %) in JJ array measurement article page 12. I wonder how practical it is to weld test leads, so there's no solder or thermal EMF. I know that this will sound crazy, and proba

Re: [volt-nuts] low emf solder

On 29 October 2016 at 14:51, NeonJohn wrote: > > > On 10/28/2016 08:39 PM, Dr. David Kirkby (Kirkby Microwave Ltd) wrote: > > > I wonder how practical it is to weld test leads, so there's no solder or > > thermal EMF. > > > > I know that this will sound c

[volt-nuts] Availability of 3458A in Europe after the end of 2016.

The 3458A page on the Keysight website is interesting. "Notice for European Union Customers: This product is not updated to EU RoHS compliance and can be ordered via Keysight directly or Keysight Authorized Distributors until 31 December 2016. Beyond this date, the product can still be purchased f

Re: [volt-nuts] Availability of 3458A in Europe after the end of 2016.

uropean Union. The regulations we introduce will not have to have such a large committee for approval, and don't need to be translated in numerous different languages. Of course, the other advantage, is I will be able to buy a 3458A if I want to !! Dr. David Kirkby Ph.D CEng MIET Kirkby Microw

Re: [volt-nuts] Availability of 3458A in Europe after the end of 2016.

On 13 November 2016 at 14:17, Chuck Harris wrote: > RoHS does not apply to test equipment. > Where do you get that from? When I was looking briefly the other day, there did not seem to be a lot of exemptions. I'm sure Keysight must be a bit more on the ball than to put that notice, if RoHS did

Re: [volt-nuts] [time-nuts] OT: ExpressPCB (cross-post from volts-nuts)

On 9 December 2016 at 19:58, BIll Ezell wrote: > Sorry if I'm behind the times, just did a new project that required a pcb, > and ExpressPCB is my go-to vendor for one-off boards. I just noticed they > now provide the low-cost boards (fixed size, 3x5, quantity 3) that I've > always ordered with si

Re: [volt-nuts] PCB Artist

On 14 Dec 2016 14:14, "Dan Kemppainen" wrote: > If it's a one off board, with a handful of components anything should work. You can always redraw it later in something else. If you have 500 components, differential signals, and controlled impedance stuff that's a different story. A handful of sur

[volt-nuts] Don't bother changing a 3457A battery if sending to Keysight for calibration.

Today I went to Keysight in Winnersh in the UK for a seminar on RF material measurements. We were given the opportunity to go for a 20 minute tour of the repair and calibration labs. Needless to say I took up the opportunity. There are 3 areas at Keysight in the UK. * Repair * Main calibration a

Re: [volt-nuts] Short term "standard" cell?

new, but to make a stable reference you need quite expensive resistors, so a used 3458A reference is attractive. But I don't know if problems making low thermal EMF joints might totally ruin the potential performance. -- Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stok

[volt-nuts] Anyone got a photo of a 3458A with "new volt" printed on it?

lt. I'd like to try to research this, and perhaps give a talk at our radio club on it. I'd like to get a picture of a 3458A with such a sticker if I could. Dave Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, C

Re: [volt-nuts] Anyone got a photo of a 3458A with "new volt" printed on it?

On 31 May 2017 at 20:57, Frank Stellmach wrote: > >> I was chatting to someone from my radio club in the pub last night, and > somehow we got onto the definition of a volt. > >> I'd like to try to research this, and perhaps give a talk at our radio > club on it. > > David, there was very good Swi

[volt-nuts] Screws in bottom of 3457A

I've done something rather stupid with my 3457A. I took it apart to replace the battery, and then seem to have mislaid the screws that hold the thing together. As far as I can see, there are 4 screws in the base. The problem is, I don't know what type they are. Could anyone with a 3457A tell me the

Re: [volt-nuts] Screws in bottom of 3457A

On 11 June 2017 at 08:19, John Phillips wrote: > If you are sending it in you could just tape the cases halves together and > let them replace the screws. You may want to check with them about it but I > would be more surprised than not if they charged you for it. > I don't want to push my luck.

[volt-nuts] Best way to measure micro Ohms

I would have thought that using AC was a no-brainer no very low resistance measurements, but commercial instruments don't use to use AC. Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd drkir...@kirkbymicrowave.co.uk http://www.kirkbymicrowave.co.uk/ Tel: 01621-680100 / +44 1621-680100 (0

Re: [volt-nuts] Best way to measure micro Ohms

On 17 September 2017 at 20:12, wrote: > The question is what accuracy you need. > No a lot. I just want to find out if there's any voltage drops that are significantly higher than I would expect. The unit makes an RF transmission line, and the loss at RF is significantly higher than predicted by

Re: [volt-nuts] Best way to measure micro Ohms

On 17 September 2017 at 21:58, Mitch Van Ochten < mi...@vincentelectronics.com> wrote: > The Keithley 2002 uses DC but automatically takes a reading of any offset > voltage and subtracts it (offset compensation). Rated accuracy on the 20 > ohm range (2 years) is +/- 26 ppm, and with 10 averages i

Re: [volt-nuts] Best way to measure micro Ohms

On 18 September 2017 at 18:36, Todd Micallef wrote: > Dave, > > Another meter is the Cambridge LOM-510A. I am not sure if it is in your > budget but there has been a review made on EEVBlog. There is one currently > on eBay with a current amplifier that I have never seen before today. It > may be

Re: [volt-nuts] Best way to measure micro Ohms

On 18 September 2017 at 23:28, george wrote: > The reason that DC is used commercially to measure resistance is simple, > if you use AC you may well get the reactive component as well as the > resistance coming into play. > That may not be an an issue with a dual-phase lock-in amplifier, as the

Re: [volt-nuts] Best way to measure micro Ohms

On 19 September 2017 at 20:32, Charles Steinmetz wrote: Looking at the pix, there appear to be lots of aluminum joints due to the > "built-up" construction, maximizing the potential for the sort of troubles > you are having. I would re-make the piece in brass, doing everything > possible to use

[volt-nuts] Power consumption of 3458A reference board / fitting one in a 3457A

I've got two different, but not totally unrelated questions. 1) Does anyone know what is the power consumption of the 3458A reference board? I was thinking of getting one, boxing it up with a battery, that allowed it to keep running without mains power. I would like to know the energy storage the

Re: [volt-nuts] Power consumption of 3458A reference board / fittingone in a 3457A

On 24 September 2017 at 08:52, Bill Gold wrote: > David: > > Your answer to question #1. I have a spare reference board setup to be > powered up on the bench. > > I measure around 36 ma when it starts cold and then around 30 ma when > it > warms up to operating temp. This is at 18 volts

Re: [volt-nuts] Power consumption of 3458A reference board / fitting one in a 3457A

On 23 September 2017 at 18:03, Tom Knox wrote: > If you want I will send you a few to play with for a few months. > Thank you very much. I'd like to have a play. I sent you a private email. Someone suggested using the DCV:DCV ratio mode to look at two references, but I don't see this facility o

[volt-nuts] Solartron (aka Schlumberger) 7081

27;ve no idea when it was last calibrated, but I suspect long ago. Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd drkir...@kirkbymicrowave.co.uk http://www.kirkbymicrowave.co.uk/ Tel: 01621-680100 <01621%20680100> / +44 1621-680100 <01621%20680100> (0900 to 2100 UK time) Regist

Re: [volt-nuts] Solartron (aka Schlumberger) 7081

On 27 September 2017 at 11:09, David C. Partridge < david.partri...@perdrix.co.uk> wrote: > I assume you've seen my website: Solartron7081/index.htm>? Yes I had. I believe your site has more about the meter than the sum total of the rest! I was surprised how little infor

Re: [volt-nuts] Best way to measure micro Ohms

On 27 September 2017 at 22:22, ed breya wrote: > I just noticed this discussion recently, so I'm late to the party, but > that never stops me from adding my one-cent's worth. > > David, regardless of the aluminum and other material issues, I think your > initial idea of using a lock-in analyzer i

Re: [volt-nuts] Best way to measure micro Ohms

On 28 September 2017 at 19:17, ed breya wrote: > Hmm. Alternating the direction of the current repeatedly and processing > the results - sure seems like that is fundamentally an AC measurement too, > despite using DC measurement equipment. > > Ed I guess the point is current/voltage can be meas

Re: [volt-nuts] Solartron (aka Schlumberger) 7081

On 27 September 2017 at 11:09, David C. Partridge < david.partri...@perdrix.co.uk> wrote: > I assume you've seen my website: Solartron7081/index.htm>? The last corporate owner of the Solartron > brand was Ametek, and their branch in Farnborough did calibrate them up to >

<    1   2