FS UK: Agilent 3458A 8.5 digit DMM

[voltsandjolts]

This is not my auction, I have no connection with the seller, just pointing this out for the volt nuts.

Starting bid £2350
https://www.ebay.co.uk/itm/225827704316

Agilent 3458A 8.5 Digit Digital Multimeter
Instrument passes self test & performs ACAL correctly.
It has not been calibrated for many years so no guarantee of the accuracy or stability.
1 volt applied from standard that is known to be +2ppm, 1 mV applied via divider
no options fitted

I think somebody on this forum said (half-joking) the only 3458A's on ebay are the drifty ones no one wants, so buyer beware.

[coromonadalix]

yes the a3 board problem  if i recall ??

https://eevblog.com/forum/metrology/hp-3458a-ad-board-spare-part-availibilty-and-cost/

see post #225

[alm]

5 units are an anecdote, not data. There is certainly a substantial risk that it's drifty, and the problem is that you probably won't find out until the return period is over. But I bought two early units from 1989-1991 and both are stable (n=2) (knock on wood).

[voltsandjolts]

Is £2500 a fair price for a drifty example?

Not that I want to get into this volt nuttery, but it does intrigue me.
It feels like purchasing this would almost be like adopting a child, although easier to sell on 
It needs care and investment for the long term. Constantly powered in a cosy environment.

[coromonadalix]

absolutely not,       like having an formula 1 car with a 4 cylinder at 80 hp

if the a3 board is drifty   it will cost lots of $ to get one,  or try to send you meter to keysight  ...  and lots $$$ to get it repaired and calibrated

and sadly ebay sellers may or may not know if their meter is problematic without the proper tests

[voltsandjolts]

It's probably worth £2500 broken up for parts.
And if it's not drifty, it's a bargain price 3458A.
But I've got a cluttered bench already.
No. Nope. No way. Hmm, well....

[chilternview]

I'd be tempted but I already have two

Don't forget that a Keysight cal is going to set the buyer back nearly £1k - and why buy one if you're not going to be sure it's in cal?

[alm]

Don't forget that a Keysight cal is going to set the buyer back nearly £1k - and why buy one if you're not going to be sure it's in cal?

Because of the excellent linearity? For metrology-grade measurements I use mine purely as ratio devices. I have better voltage and resistance standards: the 3458A's built-in DCV and resistance reference are pretty good but not amazing. So for me the 3458A is generally just measuring the ratio between the DUT and an external reference. And thanks to the magic of the extremely linear ADC and autocal, it can accurately measure those ratios without any external calibration. The exception is high frequency ACV, but those specs aren't so hot anyway. The only thing that would make it even better is if the front/rear inputs could be switched under remote control.

If you want to rely on its absolute values then you might want to send it out for calibration, but I don't consider that essential for my use.

[chilternview]

If you want to rely on its absolute values then you might want to send it out for calibration, but I don't consider that essential for my use.

Agreed, if the user has better standards that they can trust that's certainly a valid use model.

[coromonadalix]

i think the 3458  just needed 2 things

a very stable reference voltage and an precise resistor value to calibrate it

[alm]

To adjust everything but high frequency AC, you're right, you just need a very stable 10Vish DC voltage source and 10 kOhm ish resistor that you know the value of very accurately, plus a good short. The manual tells you how to make it out of a piece of copper wire. I'd argue just running this is good enough for most hobby use.

But for a proper calibration you should also verify all ranges and functions afterwards. How else can you verify uncertainties or get a report with data? That's what Keysight does if you send it to them.

[chilternview]

Of course you need to know if your voltage and resistance reference is 'accurate'.... is  it calibrated, what is its uncertainty, what is it traceable to, how much may it have drifted due to temperature and/or ageing. And do you need an accredited calibration - all depends on what you want to use the 3458A for.

[deepfryed]

I think somebody on this forum said (half-joking) the only 3458A's on ebay are the drifty ones no one wants, so buyer beware.

Out of curiosity, emailed the seller last night to ask if there's any paperwork on history / calibration & adjustments. No response 

If someone on the forum buys it, I'd be interested to know how it turns out

[Oldtestgear]

I have sold a couple of 3458A DMMs over the years. I always checked for drift before selling AND showed the data. Specifically excluding drift in a listing screams "I know it drifts".
Just my opinion but I would not pay anything like the starting price on what is  a huge gamble. 

Phil

[factory]

Or zero history and ERR on display... https://www.ppauctions.com/lot/185406/lot-1528
Not interested myself.

David

[alm]

Or zero history and ERR on display... https://www.ppauctions.com/lot/185406/lot-1528
Not interested myself.

It's always a risk, some more than others. For GBP 480 I would absolutely buy it, but I'm sure it won't stay like that. The ERR annunciator could be something innocent like the digital NVRAMs for reading stories having an empty battery, or something as big as needing a new A3 board. You have these risks with most used equipment in unknown condition, it's just that the stakes are higher here because of the repair costs. However, expect to pay a lot more for a unit with a documented drift history because obviously these are more desirable.

[veedub565]

Or zero history and ERR on display... https://www.ppauctions.com/lot/185406/lot-1528
Not interested myself.

David

I saw that and put a bid on around £400 (+VAT +fees). Not a bad price still, but I doubt it'll sell that cheap. And I already have a calibrated Datron 1281 so I don't desperately need the 3458a, although it would be nice to have.

[bastl_r]

I cannot make an offer because there is "no shipping to germany" marked.

[Oldtestgear]

I have just looked at the 3458A being auctioned by PP Auctions. It was sent to Keysight in January this year -- see electrical safety check label -- but no sign of a calibration label.

Bit strange unless it was returned as "unrepaired"  or someone has peeled the calibration sticker off to try & get a great deal? Either way it is now too expensive for me to take a punt on...........

Phil

[chilternview]

I have just looked at the 3458A being auctioned by PP Auctions. It was sent to Keysight in January this year -- see electrical safety check label -- but no sign of a calibration label.

Bit strange unless it was returned as "unrepaired"  or someone has peeled the calibration sticker off to try & get a great deal? Either way it is now too expensive for me to take a punt on...........

Phil

Yep. No cal label almost certainly means it failed, else why put it up for auction? At £1250 already its looking expensive as repair and cal is going to be in the £3k range.

[factory]

I'm suspicious that the high bidder is an alias of "reserve not met", think this will be appearing in quite a few future auctions.

Might give anyone seriously interested a chance to ask Keysight about the S/N and research if it's failed cal.

The company work outsourced calibration to still puts cal-due labels on failed items, even though it also states failed.

David

[mendip_discovery]

I'm suspicious that the high bidder is an alias of "reserve not met", think this will be appearing in quite a few future auctions.

Either a punt for nothing or a shill to get it moving.

Might give anyone seriously interested a chance to ask Keysight about the S/N and research if it's failed cal.

They don't like customers let alone someone asking for a cert/details for free.

The company work outsourced calibration to still puts cal-due labels on failed items, even though it also states failed.

If I reject something it gets a cal date but where the due date is I put rejected. But I know from a 17025 (UKAS) that they feel it should be for the customer to decide so I have to use a "Limited Calibration see Certificate" label. But they also get funny about us putting due dates on things as it is for the customer to decide, the 12-month thing is a really lazy option and was mostly promoted by companies that wanted you to send the stuff back to them each year. If a customer doesn't state a frequency we just leave it blank.

[macaba]

Or zero history and ERR on display... https://www.ppauctions.com/lot/185406/lot-1528

Approx. £3222.45 for a unit with a multislope rundown convergence error. Madness.

[chilternview]

a unit with a multislope rundown convergence error.

Just curious, but how do you know that? Did you go view it before auction?

[factory]

Or maybe asked the auction house to run the self test, or asked them for the error code, not an unreasonable request given what these make. Or asked Keyshite for a cal/repair quote against that S/N. 

I'm 99.99% certain the house won it.

David

[factory]

The company work outsourced calibration to still puts cal-due labels on failed items, even though it also states failed.

If I reject something it gets a cal date but where the due date is I put rejected. But I know from a 17025 (UKAS) that they feel it should be for the customer to decide so I have to use a "Limited Calibration see Certificate" label. But they also get funny about us putting due dates on things as it is for the customer to decide, the 12-month thing is a really lazy option and was mostly promoted by companies that wanted you to send the stuff back to them each year. If a customer doesn't state a frequency we just leave it blank.

In the past we had several people employed full time doing internal cal (with very little done externally) this got slowly reduced, by sending stuff to various external different external cal companies, with less done in house.
More recently those in charge want rid of the internal cal lab, they choose one company to send everything to, with a fixed yearly contract price (repairs not included), not sure if they choose based on, what was easiest for them, or the cheapest option.
They seem to be giving the same cal intervals, six or twelve months as in house did. When you say "customer" this will mean whoever is in charge will decide if they even notice.
It'll probably fall apart when a auditor finds one of the barely noticeable "fail"s on a cal label, some of us know what to look for & put out of use, but not all will.

David

[mendip_discovery]

It sold, for £3275

David, lots of companies have gone for this method, as they want to get rid of the hassle of dealing with calibration. The thing for me is very few of them ever look at a certificate and ask is this fit for purpose and if this item meets the requirements for being used? This I feel in a sensible sized company could almost be a full time job.

[pope]

It sold, for £3275

David, lots of companies have gone for this method, as they want to get rid of the hassle of dealing with calibration. The thing for me is very few of them ever look at a certificate and ask is this fit for purpose and if this item meets the requirements for being used? This I feel in a sensible sized company could almost be a full time job.

To me it shows that it sold for £2,325

[chilternview]

To me it shows that it sold for £2,325

[factory]

£2325 + VAT + auction fees was the one from PP auction, not ePay.

David

[bastl_r]

Apart from the fact that the device has become too expensive for me, no matter how good it still is.
How would it compare to a 7.5 digit meter. My feeling is that with the possible errors discussed, it should still be at least half a decade more accurate than a 7.5 digit multimeter.
Or?

[voltsandjolts]

An out of spec 3458A 8.5 digit meter could be as accurate as a 7.5 digit DMM, but you would still need the ~£2K Keysight cal to show show how out of spec it was

[coromonadalix]

We dont hear a lot of the ADCMT  Transmill  or the Fluke 8.5 digits or any 8.5 digits meters ...

If they have some quircks like the 3458

EDIT

Advantest R6581 ??

[Oldtestgear]

Or the Solartron 7081 *.5 digit DMM. Although there are a few threads about these on the forum.  Nice clear display but definitely a bit quirky.


Phil

[MadTux]

We dont hear a lot of the ADCMT  Transmill  or the Fluke 8.5 digits or any 8.5 digits meters ...

If they have some quircks like the 3458

If ADC is build without hybrids like U180, at least it's most likely more DIY fixable.
With HP3458A, you totally depend on Keysight for support, something I'd rather avoid.

[alm]

If ADC is build without hybrids like U180, at least it's most likely more DIY fixable.
With HP3458A, you totally depend on Keysight for support, something I'd rather avoid.

Are schematics available for the Fluke or Transmille meters like they are for the 3458A?

[coromonadalix]

dont think so,  never heard of leaked ones,   you have some   but no schematics for sure  loll

Fluke 8xxx               never saw
Advantest r6581     never saw         https://xdevs.com/fix/r6581t/
Transmille 8081       never saw

the 3458A            is known  loll

K2002                  cant remember ...  don't think so,   k2000 was partially
Solartron 7081    i think it is known,  some  float on Archive.org

[Kleinstein]

The Solartron 7081 eventually gets 8 digits, but with less than 1/10 the speed and a little residual drift and somewhat troubled auto zero to correct for this.
AFAIK there are no schematics avialable for the new fluke and the transmile meters.  For the slightly older (AFAIK not current) transmile meter there is a thread here in the forum that has some testing and reverse engeniering one the ADC. From that it looks a bit like the Solartron with added oddities. Without a schematics and service hints this could be hard to fix / test and a programmed µC or CPLD can already be a show stopper if bad.

There are full service docs on the Datron1281, the predecessor to the high end Fluke meters.
For the Solartron 8081 there is a plan around.
For the K2002 there is partial rev. engeniering (ADC, ohms part and crude voltage part) and a useful service manual to at least explain the self test errors.
For the R6581 there are quite good rev. eng. plans and even firmware analysis around here in the forum.
Still not all 8 digit meters are at the same level.

[alligatorblues]

I think somebody on this forum said (half-joking) the only 3458A's on ebay are the drifty ones no one wants, so buyer beware.

Semiconductor manufacturers use many 3458As. When they get drifty, not even out of spec, they turn them over to liquidators, and some find their way to eBay. The A3 boards come up on eBay a few times a year. You just need to save the search, and when one comes up, you'll get an email.

You just never know. Last time I needed one, a soldier on a military base had 25 of them. He probably found a box of them and knew what they are. If you go on military calibration forums, those guys can get anything you want. But you have to get to know who's who.

Defense contractors also have cal labs everywhere. So, their techs are there too. Lockheed Martin does calibration work for commercial labs, but it's very hush hush how to find the labs that are open to the outside world. I found one in FL USA. But it only does pick up and drop off.   

[Oldtestgear]

An out of spec 3458A 8.5 digit meter could be as accurate as a 7.5 digit DMM, but you would still need the ~£2K Keysight cal to show show how out of spec it was

I just paid for Keysight UK to calibrate my 3458A, at the bargain price of "only" £716.40. Note no adjustments performed.
Getting a 34470A calibrated cost £247.20 which included pre & post adjustment results.  The Instrument was within specification before adjustment but this was performed as part of the job.

All prices included VAT

[voltsandjolts]

Oh, bargain!

You state prices including VAT but they wouldn't deal with you as a private individual, have I got that right?

I have "given in" to Keysight's demand that I incorporate a company as the only way to get my 34470A calibrated.  It is definitely not a sensible option but it is pragmatic. I have completed the paperwork & notified Keysight. They have acknowledged my email & stated that full support is now available.  I hope to get the 34470A calibrated next week, with one of my newly acqured 3458As planned for late October assuming that both pass the dreaded long term drift test.

Not sure if I can help anyone else with parts or calibrations but am happy to try.  My new company is not intended to be profitable butcannot be run at a loss either.

Excluding my shipping costs to/from your office, how much would you charge to get my 34470A cal'd at Keysight, with adjustments?

[coromonadalix]

there's a difference between certification AND calibration

[voltsandjolts]

I have a plethora of certificates of calibration.
I don't have any certificates of certification.

[coromonadalix]

in my country, 

Certify the instrument work in the acceptable range or outside of the acceptable range,  no calbration

Calibration,  it was certified before, got the results, and calibrate it,  adjustment done internally or software made  etc ... 
a calibration can be done,  AND  it can get a failed status on some ranges, failed on 1 range  or failed on all   ....   because it still can not get under the acceptable ranges

normally the certification will tell all,  and the user have to choose if he / she goes thru the Calibration

mostly the Cal labs :   you can not calibrate until a certification was made prior, everything is logged ... that's how they work in my town

[alm]

in my country,

What country is that, that is not a member of the BIPM, and does not adhere to the International Vocabulary of Metrology (see section 5.18 / page 39)?

[coromonadalix]

https://www.bipm.org/en/countries/ca

and you refer on section 3


i'm not the one who use theses terms,  but there is differences, i simply wrote what happen in some of our cal labs  other i dont know

I ship  over 10K $$ of stuff at a 1 or 2 year intervals  and they clearly state, is it a certification or a calibration ?

A certification can be issued without a calibration


I repeat

If after the certification you want to do a calibration, you can  it's your choice if it goes well or not, because there may or was possible problems,  they can or could be resolved by a calibration,  if  say:  you have a failed range,  the calibration get an incomplete status and it is not considered fully calibrated therefore  it still get some failed status in the paperwork, it as i said  it will be recorded

After some repairs if it's possible, you can retry a calibration ... or not,   bit it was already logged as having one problem


I'm not talking about Keysight labs, there are others in Canada, Quebec city, Montreal, Ontario   etc ...

Some of my Gossens meter had to be shipped very far to be kept under the DAKKS system, some of my 34401 at the time (one was fully calibrated)  the others where certified, and theses old 20 years pup where still in the ranges ...

some scopes where calibrated,  others not ... old tds220,  tds 2k series

Even some Cal labs have problems to deal with  old thanks like TDS7254B and a TDS7404, have to ship them far away too'

now shipping lots of brand new Siglent stuff  we bough, and they will be "calibrated" because they work in critical stuff

even i  i'm lost at word,   it's some basic examples ... for sure it is contestable if some wants to

even some crappy (but working well) 3x bought juntek jds2900 at 100$ usd  had been certified for 160CAD x3 ??    witch is a pure joke, i've done some battle with the certification guy, he simply dont care,  i said its not worth it

[alm]

i'm not the one who use theses terms,  but there is differences, i simply wrote what happen in some of our cal labs  other i dont know

I ship  over 10K $$ of stuff at a 1 or 2 year intervals  and they clearly state, is it a certification or a calibration ?

Please do not repeat such misleading usage. It's internationally agreed (for example in the document I referred to) that calibration is a documented measurement or comparison, and adjustment of an instrument is called adjustment. You can ask for calibration with or without adjustment. For some instruments asking for calibration may also get you adjustment. See for example this video:

[coromonadalix]

tell it to  the cal labs we use   ... they are the ones who scrap the good terminology / definitions etc ...  and yes  i can do bad telling it here   

if they are wrong from the start   

sadly   some and  "i include myself", dont talk like this

here calibration is not a certification for sure,  and calibration as the same usage as adjustment (the moment you change a reference value into an instrument)
even got a big red / white sticker once on a psu  "No Calibration needed" and i could still use it

and some other Canadians can or could disagree too

but i'm not here to start a war of words,   if i stepped on a land mine  thats all   boom   loll


well return to the main topics as a mod would kindly ask