3458A - black edition

[ScoobyDoo]

Hello folks - the RoHS compliant revised  version of the 3458A will be launched soon - 1st of December 2019 - in Germany by Datatec / Meilhaus and authorized KS distributors ... Some of us have already seen the early model or a presentation.

Keysight 3458A | 8½-digit digital system - bench multimeter:

Back in Black - the legacy model did not meet EU RoHS compliance requirements and was discontinued. Keysight reworked the 3458A fundamentally. In terms of RoHS compliance, Keysight has made a major overhaul of all its printed circuit boards for the 3458A. The revised 3458A is 100% compatible with your existing 3458A.

The 3458A Multimeter features an 8½-digit display, an accuracy of 0.0008% for DCV (0.0004% optional), the highest stability of 8ppm per year, combined with very fast measurement speeds with very high absolute accuracy , Therefore, the 3458A is the standard in calibration and calibration laboratories, in production fields and development laboratories around the world.

The 3458A is used for high precision DC and AC voltage measurements and DC current measurements. Applications can be found in test rigs for different tasks in meteorological institutes, development laboratories and production, where the high measuring speed is also advantageous.

What has been kept unchanged ?
Fully compatible: Same form, fit and function. Same specifications as released in 1989. Same programming codes. Same I/O connectivity. Same part number and accessories.

What Has Changed?
RoHS compliant. New color. New PCB assemblies (DC input board, AC board, A/D board, out-guard controller board, in-guard power supply board, out-guard power supply board). Extended memory (former option 001) is now standard.

KS will most likely propel the development of a high end DMM designed from scratch - to be expected in a few years from now.

Knowing that KS will focus efforts more on development of new products and the 3458A is more a cash cow - it is right moment to make a wishlist of accessories, software code snippets (Python language), ... that would be welcome with the introduction of the black edition of the 3458A - so that KS can work on that to extend the lifespan of this DMM beast ...

What would 3458A adepts like that KS focuses on next coming months ... ?

• Outdoor carrying case ...
• Python3 & RPi code snippets ...
• Improved A9 reference board - 2ppm/YR - lower 1/f noise - lower TC @ lower cost using recent technology...
• Improved A3 ADC board - new U180 with lower TC - vacuum encapsulation (no leakage)
• Any other business ... (?)

Herzlichen Grüßen/Meilleures salutations/Best regards
ScoobyDoo

[SilverSolder]

"Same specifications as released in 1989."

Our ancestors did a good job on this one!

[Dr. Frank]

And who should do that new 'development from scratch'?

These old designers are all gone, so the knowledge about the magic inside the 3458A is also gone.

The 34465A/470A is obviously a slight advancement from the 410A/411A only, a lot of copy-and-paste, done by parts of the old development team, which is finally retired.

Even this layout redesign has not been done by KS, but an external Engineering bureau, located in EU.

I really don't expect any new design any more.

Frank

[iMo]

I really don't expect any new design any more.

I wouldn't be so pessimistic. Otherwise they will close the Patent Office soon

[rastro]

It would be nice if sales of the "new" 3458A(BE) would push more of the older 3458A instruments onto the used market.   

[Kleinstein]

There is not that much incentive to change from an old aged  3458 to a new one.  There may be a few cases when the choice is repair an old 3458 or buy a new one, that now have a real option to buy a new one.

With new fast 7.5 digit meters around the market for the 3458 is now smaller than it was 30 years ago, when it also was the fastest at 7.5 digits. Today the 34470 or DMM7510 may be a good alternative in some cases, when it is more about speed or digital RMS than highest resolution.

[niner_007]

These old designers are all gone, so the knowledge about the magic inside the 3458A is also gone.

I really don't expect any new design any more.

That’s a myth, and I absolutely do not believe it, if you got the money as a corporation, you’ll get engineering minds to do it from having none or no experience, but it might take a little bit of time, from a year to two years, I have expertise and experience on this topic, you do need experience with hiring, managing and growing people however.

With the redesign, I kind of agree, but on different grounds.

[niner_007]

Regarding a new redesign, I would not believe it will be released in a few years, not even close, the new 3458A will be serviced and supported for at least 10 years, as if it were a new product, so maybe 10 years from now we’ll see a new 3458.

There are only a few options, 1) they either update and support the 3458A until eventually they don’t, and they get out of the business of making a 8.5 metrology DMM, 2) they make a successor for 3458A that is 8.5 but not metrology grade, kinda like a successor to 34470A, 3) they do a complete redesign and 4) a variant of 1) and 3) where they support the 3458A indefinitely (10-30 years), making incremental updates and localized redesigns over time, making the support scalable.

I see 1) or 2) as likely outcomes depending on business outcomes and net profit of Keysight and demand, 3) and 4) are related, and they would be driven by business assertiveness, strategic direction and top down directives. 

Keep in mind, a complete redesign might very well be a layout and new BOM, but it will never mean not using, previous architecture and designs.

I for one hope for 3), and would not look forward to a brand new complete redesign, why? No transparency, no schematics, no component level support and repair and no parts, look at Fluke or look at the 34470, with the 3458A I can buy a new one and used one from ebay, transplant the parts, and go, that is great and unique, that can’t be said of Fluke, or any new test equipment or consumer electronics that comes out and sold today. If all the parts were off the shelf, purchasable from digikey in a quantity of 1, firmware was accessible and transferable, and not locked down and encrypted, that would be a step in the right direction.

The 3458A has seen a lot of updates, the digital board is gone and completely different from original, in time they can do the same to the remaining boards, but if they maintain the boards compatibility, that would be killer, no one has done or has that, except the 3458A itself, long term support and component level repair is the dream.

[Kleinstein]

The problem I see for a 3458 redesign is a rather limited market. There are other meters to offer the low noise / high speed at the 6-7 digit  accuracy. So today's market for the 3458 may be well smaller than it was in 1989, when the 3458 was a good option for fast 6 or 7 digit readings.

A redesign of the ADC is likely not as easy - not much direct competition to the 3458 (except the new Fulke ones - maybe) and chances are the ADC in the 34470 and similar may not be that suitable to get high linearity. This is more a solution to get the high speed needed for digital AC. Difficulties start with the need to use a JJA to really do a good INL test in the 0.1 ppm range. At his level one may need full boards systems for a test. So design steps slow down quite a bit.
Chances are a new design would be quite different today. This could also mean no full software compatibility as there would be different options (e.g. different speeds, different voltage ranges). Still chances are a new design would not be so much better performance , as there are principle limits coming up.

I think they did already most of the needed (for ROHs) and easy, small, local improvements. So I don't expect many incremental updates in the near future - maybe a big fix if needed. The black edition is more like the sum of small updates.

[SilverSolder]

There is significant kudos for Keysight to be selling the leading instrument in its class, creating a halo effect that lifts all of their products.

The t&m version of the old Ford motorsport adage, win on Sunday, sell on Monday!

[iMo]

There are two important moments you have mentioned above in your posts - "1989" and "Money".
Those great, innovative, highest quality devices (and not only the 3458A) were born thanks the Cold War. The companies like DEC, HP, IBM (and their counterparts in Eastern Block too) and few others milked the Military and Governments in 1950-1989 in an unprecedented way. The military budgets (incl. Space race/exploration) were almost unlimited, hidden, at that time you got money on R&D and the highest-end equipment easily. Those high tech companies were full of money, could afford large R&D teams with most expensive and clever individuals, who worked on designs where $$ played a minor role.
After the Cold War finished (1989) most of those companies faced huge challenges. DEC collapsed, HP sold many of its divisions, IBM had restructured as well, many others simply disappeared - as they had to start mess with commercial customers.

[SilverSolder]

A lot of the high tech developed in the cold war era has now been miniaturized and is "trickling down" to the general population - for example, mobile phones.   

Test & measurement has moved on too -  e.g. the performance of a $20 Aneng 8008 would have been impossible to build in 1989 at anywhere near that price...

[niner_007]

Python3 & RPi code snippets ...
Improved A9 reference board - 2ppm/YR - lower TC @ lower cost using recent technology...

A 2ppm reference for the 3458A is/was already available from Keysight, for a sweet $2000, it can be purchased today, but I believe you’ll have to install yourself and send for calibration. Not available as an option during purchase.

What scripts would you specifically want to see? Keysight won’t likely be providing either of one. I’d love to see some C++ scripts targeting Cling (a C++ interpreter), I can use Python, but dislike it, C+/C++ or even C# is my soup :-)

Not sure how well this is known, but the 3458A has a built in Basic interpreter, a bunch of scripts that run directly on the 3458A could be useful as well. The interpreter back in the day was probably a killer feature of the 3458A, specially in the 80s when Basic was all the rage.

The neat thing about the Pi, is that you can set it up ready to go and just distribute the image (sdcard) or the Pi itself, guaranteed to Plug and Play, and just work.

Someone should make a Ubuntu based distro for T&M

[Henrik_V]

The 3458A is THE standard for a linear ADC.
(According to all voltage metrologists I had the chance to talk about that thing)
KS invest a lot of work to regain the lost knowledge.
The new black edition has the same spec for the ovious reason that a lot of qualified setups will need a one by one replacement, but I wouldn't be suprised if future publications show up some improvements.   

[dr.diesel]

rather limited market

While I agree, I still hope to see a K2002 replacement, the DMM8510.  And of-course it had better be LTFLU powered!

Though I realize not in the same class as the 3458, but still..

[iMo]

The big question is how they have replaced those special HP asics, with switches and resistor networks inside. Otherwise the parameters could be better, sure.
Also my bet would be they run the old firmware as-is without touching it (ie emulating the old cpu+rams+eeproms+ with a beefy arm).

PS: the U180 (38hot.net) among others

[niner_007]

if they update the ADC, the 3458A will live forever

[Kleinstein]

if they update the ADC, the 3458A will live forever

Updating the ADC can be tricky, even for relatively moderate changes. There may not be an easy replacement for the U180 ASIC, except for a new special chip and resistor array (maybe 2 separate parts). So if  U180 is changed - it would be more like a new DMM, no more 3458.

[iMo]

That would be interesting - I would expect 2 parts solution, as the special Asic would be expensive. Even using two identical parts, but not having them in the same package (do they heat up the U180 inside?) would be worse. On the other hand, the other modern parts around U180 may mitigate the issue somehow, imho.

[dr.diesel]

The big question is how they have replaced those special HP asics, with switches and resistor networks inside.

Any reason they simply can't make another run of the original design?  Advances in manufacturing might make this affordable over a redesign.

[iMo]

That is the million dollar question
It depends on the number of 3458A/BE units KS plans to produce. 10k, 100k, 1mil, 10mil??
With 2 "standard modern parts" solution the cost of ie. "U180" could be say $50 in 10k quantities, with a new "old" hybrid chip in that package x0 times more, imho.

[rastro]

There may also be a market for just the ADC PCB as an OEM component for other applications.  That would increase the parts volume to mitigate redesign costs.

[niner_007]

There may also be a market for just the ADC PCB as an OEM component for other applications.  That would increase the parts volume to mitigate redesign costs.

they should also sell the ADC board standalone they kind of do, but they assume will be used in 3458As

[rastro]

There may also be a market for just the ADC PCB as an OEM component for other applications.  That would increase the parts volume to mitigate redesign costs.

they should also sell the ADC board standalone they kind of do, but they assume will be used in 3458As

Who else uses these ADC PCB's in their products?

[Henrik_V]

if they update the ADC, the 3458A will live forever

Updating the ADC can be tricky, even for relatively moderate changes. There may not be an easy replacement for the U180 ASIC, except for a new special chip and resistor array (maybe 2 separate parts). So if  U180 is changed - it would be more like a new DMM, no more 3458.

They build a new one to one replacement for the ADC board. All boards can be replaced with new ones AFAIK. There was a live demonstation here at PTB. Old running unit, turn off, replace ADC board with the new one, turn on , recal, DONE

I know that there was a time lag due to rebuilding at least one ASIC ...

To run the ADC board with full spec you need some more stuff... call it a 3458    (It's still a big compensation 'computer')