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