Re: [volt-nuts] Get 10K resistor calibrated in UK

[Tom Knox]

Hi Dave;

I do not think the resistance can be adjusted if that is what you are thinking, 
they will just document the actual value.

But the most important thing is stability.

Cheers;

Thomas Knox




From: volt-nuts  on behalf of David C. Partridge 

Sent: Monday, November 6, 2017 8:43 AM
To: 'Discussion of precise voltage measurement'
Subject: [volt-nuts] Get 10K resistor calibrated in UK

I have recently acquired a Guildline 9330 10K resistor (thank you Phil).

One of my meters says 10,001.251 ohms at a room temperature of about 19.4C
which is a long way from 2.5ppm or even 12.5ppm (allowing for 5C at 2ppm
worst case).

Now the question has to be where in the UK (ideally in the Midlands) can I
get an accurate calibration of this standard resistor at a reasonable cost?

Thanks
Dave


___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

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

[Tom Knox]

Hi Dave;

The 7081 is a really great meter if working correctly. It is up there with the 
Wavetek 1281, Fluke 8508, and Keysight 3458A. The only down side is the front 
panel connector, but I have seen it converted to Banana's. I think you will 
find it much better then the 3457A even with an upgraded reference.

Cheers;

Thomas Knox
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of Dr. David Kirkby 
(Kirkby Microwave Ltd) 
Sent: Tuesday, September 26, 2017 4:56 PM
To: Discussion of precise voltage measurement
Subject: [volt-nuts] Solartron (aka Schlumberger) 7081

I've been offered a Solartron 7081 8.5 digit meter, but are having
difficulty finding out much about this. Is there any "official" place where
these can be calibrated? As far as I can see from a search of Companies
House

https://beta.companieshouse.gov.uk/company/02858371
[https://d3rubtivi36dxc.cloudfront.net/images/opengraph-image.jpg]

SOLARTRON INSTRUMENTS LIMITED - Overview (free company 
...
beta.companieshouse.gov.uk
SOLARTRON INSTRUMENTS LIMITED - Free company information from Companies House 
including registered office address, filing history, accounts, annual return, 
officers ...



Solartron Instruments Ltd was dissolved in 2013. I don't know if there is
really anybody able to calibrate these things.

Clearly the meter is not in the same league as a 3458A. but I've been
offered it for little more than the cost of a new Keysight  U1282A 4.5
digit handheld meter! I'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/
Low cost Vector Network Analyzer Calibration 
kits
www.kirkbymicrowave.co.uk
How to buy our calibration kits. Can we pay in $(USD) or € (Euros)? Kirkby 
Microwave 85033 7 GHz SMA Kirkby Microwave 85033 option 001. 7 GHz SMA with 
reverse ...


Tel: 01621-680100 <01621%20680100> / +44 1621-680100 <01621%20680100> (0900
to 2100 UK time)

Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT,
UK.
Registered in England and Wales, company number 08914892.
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

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

[Tom Knox]

Hi Dave;

I am not sure I saw you email, please contact me again off list to work out 
details.

Cheers;

Thomas Knox
Sr Test and Measurement Engineer
Ascent Concepts and Technology
4475 Whitney Place
Boulder Colorado 80305
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of Dr. David Kirkby 
(Kirkby Microwave Ltd) 
Sent: Sunday, September 24, 2017 10:10 AM
To: Discussion of precise voltage measurement
Subject: 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 on the 3457A. I think the only way to compare
two of them would be to put them in series, but back-to-back to subtract
the voltages, and look at the difference on the 3457A.


>
> Thomas Knox
>

It's odd there's someone selling LTZ1000A chips on eBay at $50 each.

http://www.ebay.com/itm/1x-LTZ1000ACH-Ultra-Precision-Reference-LTZ1000A-/111325506311
[https://i.ebayimg.com/images/g/EGYAAOSwNRdX7g25/s-l300.jpg]<http://www.ebay.com/itm/1x-LTZ1000ACH-Ultra-Precision-Reference-LTZ1000A-/111325506311>

1x LTZ1000ACH Ultra Precision Reference LTZ1000A | 
eBay<http://www.ebay.com/itm/1x-LTZ1000ACH-Ultra-Precision-Reference-LTZ1000A-/111325506311>
www.ebay.com
400°C/W Thermal Resistance for LTZ1000A Reduces. Insulation Requirements. Low 
Noise RF Oscillators. Standard Cells. | eBay!



It looks like they have been removed from PCBs with a sledge hammer - they
are heavily scratched and/or dented. The sellers seems to have sold quite a
few, yet the chips are only marginally more expensive if bought new from
the manufacturer.

Dave
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises<https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts>
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

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

[Tom Knox]

If you want I will send you a few to play with for a few months.



Thomas Knox
Sr Test and Measurement Engineer
Ascent Concepts and Technology
4475 Whitney Place
Boulder Colorado 80305
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of Dr. David Kirkby 
(Kirkby Microwave Ltd) 
Sent: Saturday, September 23, 2017 8:45 AM
To: Discussion of precise voltage measurement
Subject: [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 batteries would need to keep it running for 2 days.

2) Would there be any point fitting a similar board, with an LTZ1000A in a
3457A 6.5 digit meter? Would it be practical? I wonder if the drift on the
3457A's reference is significant, and so a LTZ1000A would be a worthwhile
upgrade. Or is the main drift not the voltage reference, and so such an
"upgrade" would be a total waste of time/money?

Dave
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

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

[Tom Knox]

Hi Dave;

In a more detailed response to your question, i do not know a great deal about 
the 3457A but in recent years I have had multiple 3458A's

on my bench at a time and I have found on those instruments the AD drift can 
very often be greater then the reference drift. A-Cal will correct the drift 
but raw data then has a saw tooth appearance. Both A3 board and reference board 
can vary greatly in unit meeting "Spec".

I have copied a fellow Volt-Nut will who has spent a fair amount of time 
characterizing both the 3458A and 3457A and may have more insight on the 3457A 
drift and linearity. If you want to play with a few 3458A ref boards send me an 
address I am not sure what the current eBay type price is but if you want to 
keep one or both sell them for a better price in a small payback for your 
continuing contributions to the Time/Volt-Nuts forums.

Cheers;

Thomas Knox
Sr Test and Measurement Engineer
Ascent Concepts and Technology
4475 Whitney Place
Boulder Colorado 80305
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of Dr. David Kirkby 
(Kirkby Microwave Ltd) 
Sent: Saturday, September 23, 2017 8:45 AM
To: Discussion of precise voltage measurement
Subject: [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 batteries would need to keep it running for 2 days.

2) Would there be any point fitting a similar board, with an LTZ1000A in a
3457A 6.5 digit meter? Would it be practical? I wonder if the drift on the
3457A's reference is significant, and so a LTZ1000A would be a worthwhile
upgrade. Or is the main drift not the voltage reference, and so such an
"upgrade" would be a total waste of time/money?

Dave
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

Re: [volt-nuts] 3458A HFL Question

[Tom Knox]

Thanks Frank, I had always assumed the HFL option was simply a select A9 
reference like option 002, but I recently read that HFL instruments have/had 
improved A1 boards. I worked on an Agilent Branded meter with the HFL Key 
overlay and a HFL A9 but did not notice if the unit had a different part number 
on the A1 board. (that was before I was aware of a possible difference). I know 
the H01 1000 VAC option has a different A103458-91002 , A2 03458-91000, board 
and A10 03458-91001 switch all with distinct part numbers. That said I have 
never seen anyone mention a HFL A1 part number, which  would make sense if as 
you pointed out the units later then mid 90's all had the superior parts. I 
wonder if the early HFL units had unique A1 part numbers? What is also 
interesting is all the attention paid to the A9 reference when in my humble 
opinion the A3 boards has a wider (huge) range of performance with some far 
exceeding spec. Yes, you can easily A-Cal out the A/d drift but I have several 
mete
 r in my lab that have virtually no A/D drift. I am surprised that 
Keysight/Agilent/HP  has never offered select A3 boards paired with select 
Option 002 A9 boards (offered as perhaps option 003). In addition I have 
wondered why Keysight have not done some sort of an update when redesigning the 
processor board to add a better user interface such as a color touch screen 
with GUI and advanced on screen data logging and math functions. I guess we 
Volt-Nuts are a smaller market then I would like to think. That said what other 
product of any type designed in the late 80"s is still State of the Art? Truly 
amazing

Cheers;

Thomas Knox
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of Frank Stellmach 

Sent: Friday, July 21, 2017 1:15 AM
To: volt-nuts@febo.com
Subject: [volt-nuts] 3458A HFL Question

Thomas,

that has been discussed recently on eevblog, and another volt-nuts
stated, that the only difference was the implementation of a VHP101, 40k
resistor for R207. This information was supposed to come directly from
keysight, but has been deleted by the user.

The VHP101 has a T.C. < 0.3ppm/K, and is oil filled, so 2ppm/6yr drift
might be assumed, according to the Vishay datasheets.

This resistor was routinely assembled in the standard instruments since
about 1996, so 3458As younger than that should also be more stable,
although HPAK never adapted the specification. These resistors were all
marked by hand, i.e. an individual code on top of the housing, so a
selection may have taken part.

This VHP101 may improve the ACAL OHM T.C. and OHM 1-year-drift over the
original b.m.f. resistor, but the ACAL T.C. is not specified in the HFL
datasheet. The transfer accuracy also does not reflect correctly this
improvement, as the drift over 10min and 0.5°C for 10kOhm and 100kOhm
would only be related to the Ohm mode resistor array, RP300, which
obviously was not changed, and has a T.C. of about 3ppm/K, which would
yield a transfer stability of 1.5ppm for a 0.5°C change.

I think, the HFL specification is a hoax, especially, as nobody ever has
seen a real HFL instrument.

Frank


 > Does anyone know how to identify a 3458A HFL A1 board?
 >The HFL A9 is part number 03458-66529, but I have never seen a part
number for the A1 board with superior resistance measurement.
 >And does the A1 use select parts like the A9 or different parts?
Thanks: Thomas Knox

___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

[volt-nuts] 3458A HFL Question

[Tom Knox]

Does anyone know how to identify a 3458A HFL A1 board? The HFL A9 is part 
number 03458-66529, but I have never seen a part number for the A1 board with 
superior resistance measurement. And does the A1 use select parts like the A9 
or different parts?

Thanks:

Thomas Knox
1-303-554-0307
act...@hotmail.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.

Re: [volt-nuts] Extenders for the Datron 4800 series of calibrators?

[Tom Knox]

Hi Dave;

Count me in.

Cheers;


Thomas Knox
Sr Test and Measurement Engineer
Ascent Concepts and Technology
4475 Whitney Place
Boulder Colorado 80305
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of David C. Partridge 

Sent: Tuesday, July 18, 2017 11:45 AM
To: 'Discussion of precise voltage measurement'
Subject: [volt-nuts] Extenders for the Datron 4800 series of calibrators?

Are you interested in purchasing extenders for a Datron 4800 series
calibrator?   If so I'm considering getting some made up.

Price will depend on how much interest and they won't be small PCBs.  By way
of guidance, back in 2011 I had 25 extenders of a similar size to the large
boards made and the unit cost was USD28.

Let me know if you are interested.

Cheers
Dave



___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

Re: [volt-nuts] Current Button for Datron calibrator (4800, 4805, 4807, 4808)

[Tom Knox]

On all items Wavetek I think you best option is Dave at Low Thermal in Tx. I 
know at one point he was making replacement front panels for the 480X series. 
If anyone has parts and manuals it would be Dave.

Cheers;

Thomas Knox




From: volt-nuts  on behalf of David C. Partridge 

Sent: Monday, July 3, 2017 12:22 PM
To: 'Discussion of precise voltage measurement'
Subject: Re: [volt-nuts] Current Button for Datron calibrator (4800, 4805, 
4807, 4808)

Ken

Thank you for contacting Mr Datron!  I've emailed the Fluke service centre, 
though whether the new Danaher managed organisation will be prepared to help is 
an open question.

I believe that I know the location of a manual set for the 4808 with a 
co-located A3 scanner.

What I don't know is how complete those manuals are.

Cheers
Dave

-Original Message-
From: volt-nuts [mailto:volt-nuts-boun...@febo.com] On Behalf Of Ken Peek
Sent: 01 July 2017 20:48
To: volt-nuts
Subject: Re: [volt-nuts] Current Button for Datron calibrator (4800, 4805, 
4807, 4808)

Hi David,

I already checked with John Pickering, and he does not have anything for the 
480x series.  He suggested contacting the Fluke service center there in the UK. 
 Fluke bought Datron/Wavetek, and they inherited all of the manuals, parts, and 
IP.  IIRC, the UK Fluke service center *IS* the old Datron factory/service 
department.  John said that that service center has ONE "golden" manual set for 
the 480x services calibrators-- but it is in paper format.  I suspect that they 
don't have the bandwidth to convert that into a nice PDF, or they would have 
done that already.  You might get in touch with them, to see if some kind of 
deal can be struck-- where you agree to scan the manuals and make a PDF for 
them (if they give you access).  It might be a thing where you would have to 
bring your laptop and scanner to their office (so the paper manuals never 
leave).  If you DO get the opportunity to make this happen-- please upload it 
for the rest of us to use!

As for the parts-- again, maybe the Fluke service center has some parts in a 
dusty old box somewhere that might have what you need.  You might want to get 
to know them-- perhaps some premium beer (or ale) at the local pub will help 
... ?

Cheers,
Ken
==

*David C. Partridge* david.partridge at perdrix.co.uk 

*Fri Jun 30 14:04:56 EDT 2017*

I'm on the lookout for a button for a Datron 4800 series calibrator which

may be a bit of a long shot.


It's the one between the Ω and AC buttons with the Legend "I" (uppercase

i).


An even longer shot - my front panel is a bit bashed - has anyone got one

spare?


You never know someone may have a spares mule!

Also (Ho! Ho!) does anyone know the whereabouts of a complete Operator

manual (with the Verification and Calibration sections), and the Service

Manual for a 4808?


Thanks

Dave

--
___
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.
___
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.

Re: [volt-nuts] Wavetek Buttons, was Current Button for Datron calibrator (4800, 4805, 4807, 4808)

[Tom Knox]

If anyone ever decides to set up 3D printing for Wavetek 1281.1271, 4920, and 
4950 they would have a small gold mine on their hands. Those buttons all 
discolor very badly make a great instrument look old and dated. If they did 
them with the writing recessed in a contrasting color, which should be easy 
with 3D printing they would breath new like into these meters. I myself would 
buy at least 10 sets.

Cheers;

Thomas Knox




From: volt-nuts  on behalf of David C. Partridge 

Sent: Monday, July 3, 2017 11:47 AM
To: 'Discussion of precise voltage measurement'
Subject: Re: [volt-nuts] Current Button for Datron calibrator (4800, 4805, 
4807, 4808)

Mark,

Yes, my fall-back position is to do a 3D design (the tricky bit will be the bit 
that locks onto the plunger, and the transparent circular window for the LED 
light).

Dave
-Original Message-
From: volt-nuts [mailto:volt-nuts-boun...@febo.com] On Behalf Of Mark Sims
Sent: 01 July 2017 17:30
To: volt-nuts@febo.com
Subject: [volt-nuts] Current Button for Datron calibrator (4800, 4805, 4807, 
4808)

I used to make button / keytops by making a mold of a compatible one in clay or 
silicone rubber and filling it with epoxy followed by a lot of fiddly work 
carving out the interface to the keyswitch plunger.

These days 3D printers are your (frustrating) plastic pal who's fun to be with.
___
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.
___
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.

Re: [volt-nuts] New Volt?

[Tom Knox]

If it is of any interest NIST has just compared two of their PJSV's and it is 
in the 10-12 range.

https://www.nist.gov/srm/sri/standard-reference-instruments/sri-6000-series-programmable-josephson-voltage-standard-pjvs

[https://www.nist.gov/sites/default/files/styles/480_x_480_limit/public/images/srm/130307-first-nim-pjvs.jpg?itok=21EbYlCO]

SRI 6000 Series Programmable Josephson Voltage Standard 
...
www.nist.gov
The Programmable Josephson voltage standard (PJVS) is an instrument that 
generates stable, quantum-accurate, direct-current (DC) voltages that are 
programmable over ...

They also achieved the 1 volt threshold last year on the AC Josephson.

Also of possible Volt-Nut interest, I have been characterizing a number of 
3458A over the past year and on interest; I always assumed that most of the 
drift was from the Zener, but actually the A/D's are also a major factor. You 
would think with all the design updates Keysight could find a better A/D then 
the 1988 design.

Enjoy

Thomas Knox
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of Frank Stellmach 

Sent: Wednesday, May 31, 2017 1:57 PM
To: volt-nuts@febo.com
Subject: [volt-nuts] Anyone got a photo of a 3458A with "new volt" printed on 
it?


 >> 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 Swiss metrology school in 2007, Les Houches,
where Blaise Jeanneret published a concise presentation about the Volt,
its definition and history. Unfortunately, this is nowhere online anymore.

I could send it to you, if you were interested.

Frank

___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

[volt-nuts] Sorry: Low-cost Josephson Junction Array Corrected link

[Tom Knox]

Hi Ken;

I corrected the link. There is a lot more to a voltage standard then the Zener, 
a very reasonably priced alternative to a JJA may be a Fluke 732A.

These boxes have been in use for years and their characteristics have been 
extensively documented.

This link may also be of interest.


http://assets.fluke.com/appnotes/calibration/deaver_msc01.pdf

PREDICTABILITY OF SOLID STATE ZENER 
REFERENCES
assets.fluke.com
PREDICTABILITY OF SOLID STATE ZENER REFERENCES David Deaver Fluke Corporation 
PO Box 9090 Everett, AW 98206 425-446-6434 david.dea...@fluke.com Abstract - 
With the ...

Cheers;

Thomas Knox




From: volt-nuts  on behalf of Ken Peek 

Sent: Wednesday, October 19, 2016 4:35 PM
To: volt-nuts
Subject: Re: [volt-nuts] Low-cost Josephson Junction Array

@Vince:

Thank you for the link!  Very informative!  There is also a nice video
showing some of the lab techniques, and some cautions working with
cryogenic liquids.

I would also like to explore miniature cryocoolers-- as these might be able
to support a small lower power array (1V) if it doesn't dissipate too much
power...

There is already some progress in this area with a QHR made from graphene
(at the NPL in the UK).  So, maybe the same cryocooler could be used also
for the low-cost JJA ?

Having a 10V (fixed output) JJA and a 12K9 QHR would be the basis to
calibrate all other electrical standards in a lab.  It would be nice to
have these sitting in their cryocoolers cranking out volts and ohms
practically indefinitely (or as long as you want)-- and if one has even a
rubidium atomic clock, then no external signals or standards of any kind
would be needed.  Well, that and a triple-point of water cell (which I
have) for temperature calibrations.

-Ken
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

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

[Tom Knox]

Hi Ken;

There is a lot more to a voltage standard then the Zener, a very reasonably 
priced alternative to a JJA may be a Fluke 732A.

These boxes have been in use for years and their characteristics have been 
extensively documented.

This link may also be of interest.

https://www.google.com/search?q=zenner+732a&ie=utf-8&oe=utf-8

Cheers;

Thomas Knox




From: volt-nuts  on behalf of Ken Peek 

Sent: Wednesday, October 19, 2016 4:35 PM
To: volt-nuts
Subject: Re: [volt-nuts] Low-cost Josephson Junction Array

@Vince:

Thank you for the link!  Very informative!  There is also a nice video
showing some of the lab techniques, and some cautions working with
cryogenic liquids.

I would also like to explore miniature cryocoolers-- as these might be able
to support a small lower power array (1V) if it doesn't dissipate too much
power...

There is already some progress in this area with a QHR made from graphene
(at the NPL in the UK).  So, maybe the same cryocooler could be used also
for the low-cost JJA ?

Having a 10V (fixed output) JJA and a 12K9 QHR would be the basis to
calibrate all other electrical standards in a lab.  It would be nice to
have these sitting in their cryocoolers cranking out volts and ohms
practically indefinitely (or as long as you want)-- and if one has even a
rubidium atomic clock, then no external signals or standards of any kind
would be needed.  Well, that and a triple-point of water cell (which I
have) for temperature calibrations.

-Ken
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

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

[Tom Knox]

Hi Paul;


I think there are some other manufactures and I have even seen several used 
systems in various states of disrepair on eBay over the past few years.

But I think the NIST system probably represents a real value since the system 
price does not fully represent all the research and development dollars spend 
reaching the current state of the art system what would be added to a privately 
developed system. If anyone does ever have an interest I would be glad to 
direct them to the correct person to answer technical or pricing questions. I 
am also glad to find and post answers through the Volt-Nut form regarding our 
research since the progress of science is a major part of our mission.

Cheers;



Thomas Knox
NIST



From: volt-nuts  on behalf of Poul-Henning Kamp 

Sent: Wednesday, October 19, 2016 12:37 PM
To: Discussion of precise voltage measurement; Ken Peek
Subject: Re: [volt-nuts] Low-cost Josephson Junction Array


In message 
, Ken Peek writes:

>Where in the world do I *get* one of these things?  How much does it cost?

I belive NIST is still the major manufacturer in the market.

--
Poul-Henning Kamp   | UNIX since Zilog Zeus 3.20
p...@freebsd.org | TCP/IP since RFC 956
FreeBSD committer   | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

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

[Tom Knox]

Hi Ken;

I am not sure what amount is reasonable. The NIST Programmable JJA system is 
around 400K and has accuracy of near 10 x -12.

A number of the system components are available on the used market, and I 
cannot speak for NIST, but perhaps they would work with you if you sourced 
those components used. If that was an option you could bring the cost down 
substantially. Please feel free to contact me with any other question.

Cheers;

Thomas Knox
Sr Test and Measurement Engineer
Quantum Voltage Group
Quantum Electromagnetics Division
NIST
325 Broadway
Boulder Colorado 80305
1-303-554-0307
tom.k...@nist.gov and act...@hotmail.com



From: volt-nuts  on behalf of Ken Peek 

Sent: Wednesday, October 19, 2016 12:30 PM
To: volt-nuts
Subject: [volt-nuts] Low-cost Josephson Junction Array

Does anyone know where I can get a JJA at very low cost?  It does not have
to be the "programmable" type-- it would be OK if it only produces a single
voltage, e.g. 10V or 1V.

I was looking at the ETL of Japan-- they have one based on Titanium (or
something) that works at slightly higher temperatures, and makes 1V-- so
good for liquid helium or a cryo-cooler (but not liquid nitrogen).

Where in the world do I *get* one of these things?  How much does it cost?

Ideas anyone?

-Ken
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

Re: [volt-nuts] HP 3458A

[Tom Knox]

Hi Hicham;

The real experts are at Keysight. I do work with these a bit, but am not 
familiar with this error and would be very interested in what the problem turns 
out to be. If you do not already have one I recommend purchasing the Component 
Level Service Manual from Keysight.

Sorry I could not be of more help.

Best Wishes;

Thomas Knox
Sr Test and Measurement Engineer
Ascent Concepts and Technology
Boulder Colorado 80305
1-303-554-0307
act...@hotmail.com



From: volt-nuts  on behalf of Hicham Chamsi 

Sent: Thursday, September 15, 2016 11:15 AM
To: volt-nuts@febo.com
Subject: [volt-nuts] HP 3458A

HP 3458A DMM ISSUE
H
Hier
moi
HI to all volt-nuts I receive an email from volts nut, so i learn from this
email that you are expert, please i need a help on error 205 out of range
95. i follow the instruction of Illya but no result
HP 3458A ISSUE
Hello to all

I receive an email from volts nut, so i learn from this email that you are
expert and you can help me, please i need a help on error 205 out of range
95.

i follow the instruction of Illya but no result, i hope you could help me.

also i want the equivalent of Jfet transistor N channel 1855-0743, i look
too long for this i don't get any characteristique in order to substitute
it.


Best Regards

Hicham

Répondre
Transférer
Facture Iam juin Juliet
Réception
H
Hier
*moi*
___
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
volt-nuts Info Page - American Febo 
Enterprises
www.febo.com
volt-nuts is a low volume, high SNR list for the discussion of precise voltage 
measurement and related topics. To see the collection of prior postings to the 
list ...


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.

Re: [volt-nuts] HP 3458A/HFL : looking for information/photos/fw

[Tom Knox]

Purchased new the HFL 3458A is exceptional. That said, it is my understanding 
that the HFL has the exact same circuit topography but uses select parts. Now 
here is where things get fuzzy, in the case of used 3458A's the parts often 
improve with age. So it is difficult to know without characterizing you meter 
as it ages as well as detailed knowledge/data on other 3458A's the degree of 
improvement if any and therefore whether the expense would be justified. Or if 
the new components would age as gracefully. I am not sure of exact firmware 
differences, perhaps someone can add information on that. Over the years I have 
seen a number of 3458A regardless of options that dramatically exceed their 
specs. The point is if you have one of those "golden" 3458A's don't let go of 
it. I hope that helps.

Cheers;


Thomas Knox




From: volt-nuts  on behalf of John Phillips 

Sent: Tuesday, September 13, 2016 10:23 PM
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] HP 3458A/HFL : looking for information/photos/fw

While talking with hp I was told the options Fluke orders. All are
available to anyone who wants to buy one.

On Tue, Sep 13, 2016 at 9:06 PM, Illya Tsemenko  wrote:

> Hello to all volt-nuts,
>
>
>
> Considering to pimp-up my DVM for a while, but would like to know first if
> anyone here saw actual PCB photos or have any information of what hardware
> actually different in Fluke's HFL version of 3458A. Based on Fluke's manual
> DC reference (A9 PCBA) and reference resistors on A1 PCBA got improvements.
> Firmware is also likely to be bit different, as HFL comes with
> preprogrammed macro's on keypad.
>
>
>
> If anyone have information about HFL, or have access to such instrument,
> I'd appreciate any hints and details.
>
>
> ___
> 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.
>



--

*John Phillips*
___
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.

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

[Tom Knox]

Hi All;

One thing to check for 0n the 2001 is leakage on the electrolytic caps. 
Especially the early ones (Identifiable by the finer mesh fan filter) commonly 
have this problem and if unattended the oil eats the traces making repair a 
real nightmare.

Cheers;

Thomas Knox




From: volt-nuts  on behalf of Dr. David Kirkby 
(Kirkby Microwave Ltd) 
Sent: Sunday, June 26, 2016 3:29 PM
To: Discussion of precise voltage measurement
Subject: 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 underdeath, which
covers a screw, is still there, but the screw has clearly been undone, so
the seal is "broken". I'm interested to know if it is necessary to undo the
case to calibrate the 2001, or whether it can all be done from the front
panel, probably removing that sticker on the front.

There are a few things I am not happy about this - the front panel appear
to move far more than I would expect. Depressing one key seems to make
several keys nearby go retreat towards the back of the unit, although it
appears to function.

I was a bit surprised when I put it on the 2 A range, with no leads
connected, the current is showing as high as 6 mA at times. This seems odd
given the current is obviously zero. I realize leaving the leads open on
voltage is going to lead to undefined results, but I would have expected on
current for the meter to read very close to zero.

If I put it on "auto", on DC current, with no leads, the reading is going
as high as 20 nA - there's noise on the last 3 digits. I don't know if that
makes any sense. The update rate is very fast, so perhaps that's to be
expected unless one increases the integration time.

But there are a few things making me think this meter might have issues. A
rather strange smell was initially evident, but that seems to have cleared.
The movement of the keys seems very odd. I will almost certainly return
this.


>
> If you have 14 days, run it through the paces and perform self-tests. There
> are some test scripts here https://xdevs.com/article/dmm_noise/ to see if
xDevs.com | DMM noise measurement test 
project
xdevs.com
Test project of bench DMM noise levels evaluation, using DCV ranges and various 
NPLC settings.


> the meter is measuring close to others.
>

Thanks, I will take a look.

My computer that has the GPIB board in is is rather sick at the minute. I
need to sort out what is wrong with it, as its the only convenient computer
to have a controller card in.

Dave
___
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.

Re: [volt-nuts] Datron 1271 AC Option

[Tom Knox]

There are actually two AC options for the 1271 Option 10 and the high accuracy 
option 12 which I believe is the same as in the 1281
If that is true I would assume you could also "plug and play" a 1281 AC board. 
i would need to check my service manuals to be sure.
Perhaps someone more knowledgeable could weigh in.
Thomas Knox



> From: g...@networkinggurus.com
> To: volt-nuts@febo.com
> Date: Sat, 20 Jun 2015 19:36:06 +
> Subject: Re: [volt-nuts] Datron 1271 AC Option
> 
> Would you sell the spare Option 10 and what would you want for this board. I 
> have purchase a 1271 and would like to get this option to make it a complete 
> meter.
> 
> ___
> 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.

[volt-nuts] External Freq Reference Mod for 3458A?

[Tom Knox]

Does any of the Volt-Nuts brain trust have any experience adding an external 
Frequency Reference on the 3458A.
There is a 20MHz reference on the A/D board but externally clocking it has 
affected linearity collecting data off a 10VDC reference that looks a little 
like a hanging bridge I have seen before between GPS and oscillator sync. Is 
there another clock?  Thanks for any thoughts.

Thomas Knox


  
___
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.

Re: [volt-nuts] Guildline Standard Resistors -- Oil bath temp?

[Tom Knox]

Hi Richard;
The temperature stability is more important then the exact temperature. But 
this is the exact info.
 Values below 10MΩ are calibrated in flowing oil at 25C, referred to the unit 
of resistance as maintained by the National Research Council of Canada (NRCC) 
or the National Institute of Standards and Technology (NIST) and expressed as a 
total uncertainty with a coverage factor of k=2.  Values above 1MΩ are 
calibrated in air at 23C.
Cheers;
Thomas Knox



> From: richiem5...@gmail.com
> Date: Sat, 23 May 2015 21:32:23 -0700
> To: volt-nuts@febo.com
> Subject: [volt-nuts] Guildline Standard Resistors -- Oil bath temp?
> 
> Anyone know what temperature Guildline used for the oil bath of the precision 
> resistance standards?
> ___
> 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.

Re: [volt-nuts] How accurate is a fluke after 9 years

[Tom Knox]

What is the group consensus on Vishay metal foil?
Thanks 

Thomas Knox



> From: hol...@hotmail.com
> To: volt-nuts@febo.com
> Date: Sat, 16 May 2015 18:22:22 +
> Subject: [volt-nuts] How accurate is a fluke after 9 years
> 
> Think twice about those Vishay metal film resistors...  they have known 
> stability problems (particularly concerning humidity).  Also they can have 
> problems meeting their own specs.  There is an active thread of eevblog.com 
> concerning the issue.   Consensus seems to be precision wire wound resistors 
> are a better choice.
> 
> 
> These will be replaced by 2 vishay 0.01% resistors which are hopefully more 
> stable. 
> ___
> 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.

Re: [volt-nuts] How accurate is a fluke after 9 years

[Tom Knox]

The Fluke 5700A and 5720A as well as the Wavetek 4808 and 4800A are pretty 
amazing I have seen several that appear to have been abused for years without a 
Cal and are still spot on. Same with many of the HP and Agilent 3458A's.
It seems I see more broken then out of spec.
Thomas Knox



> From: tmical...@gmail.com
> Date: Fri, 15 May 2015 15:17:19 -0400
> To: i...@electronicsandbooks.com; electronicsandbo...@yahoo.com; 
> volt-nuts@febo.com
> Subject: Re: [volt-nuts] How accurate is a fluke after 9 years
> 
> Frans,
> 
> Do you perform an in-house calibration with a 10V reference and 1 ohm & 10k 
> resistors? I have been studying the recommended calibration intervals of 
> Fluke's 57xx series calibrators and I wonder how well the unit maintains its 
> stability over long intervals between trips to a cal lab.
> 
> Also, if you don't mind, would you give a ballpark figure for the cost of cal 
> from your cal lab?
> 
> Todd
> 
> Sent from my iPad
> 
> > On May 15, 2015, at 14:50, Electronics and Books via volt-nuts 
> >  wrote:
> > 
> > My Fluke 5700A calibrator was calibrated today after 9 years. It displays 
> > how much it deviated from the last calibration. For the both voltage 
> > references i got 0.0 ppm and for the internal 10k resistor -1.7 ppm.
> > Only the amplifier for the 11-22 volt range drifted 1700 ppm for it depends 
> > on a voltage divider composed of two normal metalfilm resistors. These will 
> > be replaced by 2 vishay 0.01% resistors which are hopefully more stable.
> > 
> > Regards
> > 
> > Frans
> > 
> > 
> > 
> > Discere ne cesses
> > ___
> > 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.
  
___
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.

Re: [volt-nuts] "*WAY* too expensive for even Keysight to redesign"

[Tom Knox]

I think most of the top companies were founded by scientists and engineers and 
because of their roots in the scientific community they were very customer 
driven, but it seems recently most of the test and measurement companies have 
become stock-holder driven as the management with a background in science 
retire. In addition many of these large companies buy up the small start-ups 
from the Scientist and engineers that created them as an alternative to in 
house R&D. Once purchased they are quickly transisioned to the stock-holder 
driven model. Sadly in some cases I think the philosophy is to buy all the 
competitors and control the market to the point that they don't need to provide 
the same level of products, support, and service we enjoyed in the past since 
there are few alternatives.  In this paradigm shift I think Keysight is better 
then most. I keep hoping they design a new meter to replace the 3458A or at 
least redesign the digital portion with a more freindly user interface,  per
 haps a menu driven color touch screen and the ability to stored and display 
data graphically. Who knows they may have something in the works.

Thomas Knox



> From: alan.ambr...@anagram.net
> To: volt-nuts@febo.com
> Date: Thu, 14 May 2015 16:36:38 +
> Subject: Re: [volt-nuts] "*WAY* too expensive for even Keysight to redesign"
> 
> Hi,
> 
> 
> >>> Fluke has ... replaced the vacuum display with an LCD.
> 
> 
> 
> I'm starting to worry about the great US test gear manufacturers :)
> 
> 
> 
> Alan
> ___
> 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.

Re: [volt-nuts] HP-3458a display board

[Tom Knox]

Hi Randy;
I saw the same thing, That is a great deal, I though they were much more 
expensive. Even at half the price I would use the Keysight exchange program 
since they recently started offering free courier pick up, In addition you 
would have a warranty and most likely have a new VFD.
Cheers;
Thomas Knox

Ascent Concepts and Technology

4475 Whitney Place
Boulder Colorado 80305

1-303-554-0307

> Date: Wed, 15 Apr 2015 14:39:38 -0700
> From: randyevans2...@gmail.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] HP-3458a display board
> 
> FYI,
> 
> I contacted Keysight and found the exchange program is still in place.  The
> PN is 03458-69517 and the price is $278.
> 
> Randy Evans AE6YG
> 
> On Wed, Apr 15, 2015 at 12:05 PM, Randy Evans 
> wrote:
> 
> > I need to replace the display board for my HP-3458A (several dim to
> > missing pixels).  There used to be a swap program for the display board but
> > I can't find it on Keysight's website.  Does anyone know if it's still
> > available?  If so, how do I find it?
> >
> > Thanks,
> >
> > Randy Evans
> >
> ___
> 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.

Re: [volt-nuts] HP-3458a display board

[Tom Knox]

Hi Randy;
I think I have a few good display boards I would sell for about half price, If 
you are interested contact me directly off list.
Cheers;
Thomas Knox

Ascent Concepts and Technology

4475 Whitney Place
Boulder Colorado 80305

1-303-554-0307

> Date: Wed, 15 Apr 2015 12:05:44 -0700
> From: randyevans2...@gmail.com
> To: volt-nuts@febo.com
> Subject: [volt-nuts] HP-3458a display board
> 
> I need to replace the display board for my HP-3458A (several dim to missing
> pixels).  There used to be a swap program for the display board but I can't
> find it on Keysight's website.  Does anyone know if it's still available?
> If so, how do I find it?
> 
> Thanks,
> 
> Randy Evans
> ___
> 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.

Re: [volt-nuts] 3458A reference boards on ebay

[Tom Knox]

Most likely the boards are real, especially if the boards are from a seller in 
Colorado since that is where Keysight in the past manufactured and serviced all 
3458A's. They still do all calibration in Loveland (I am not sure if  Loveland 
is where service is done today) but this would mean the boards are pulls for 
either up grade to 002 or HFL boards or worse failed to meet spec. Further I 
would guess that working boards that meet spec would be retained for future 
replacements. That said the ones listed do appear genuine. If someone was 
thinking of duplicating the PCB I may be able to provide one to disassemble and 
repopulate afterwards. It would be interesting to have a few boards to 
experiment with.
Cheers;
Thomas Knox



> Date: Fri, 30 Jan 2015 13:24:30 +
> From: drkir...@kirkbymicrowave.co.uk
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] 3458A reference boards on ebay
> 
> On 30 January 2015 at 12:25, Will  wrote:
> > The boards are factory rejects.
> 
> I doubt all boards on eBay are in this category. Some are probably
> quite genuine, some may be rejects, and it would never surprise me if
> some are counterfeit. The problem is, I have no idea what ones are
> what.
> 
> I don't know what the problems sourcing the parts for making a
> reference would be, but if a number of people wanted to make one from
> parts, perhaps someone could produce a PCB and people contribute
> towards the cost of it. Maybe leave people to get their own reference
> chip, as there are different grades of that. But things like the
> precision resistors may be easier to buy in a quantity of 10 rather
> than 1.
> 
> I would certainly not mind buying one if a PCB was available. Even if
> it works out costing a bit more than a 3458A reference from eBay, I'd
> feel a bit happier.
> 
> Dave
> ___
> 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.

Re: [volt-nuts] 3458A reference boards on ebay

[Tom Knox]

These various Keysight/Agilent/HP references are selected during aging but are 
all identical in parts and layout. Most of these references improve with age 
and after time many standard references will meet or exceed the performance of 
002 or even the 2PPm HFL boards.
The question on these eBay boards is are they ones that failed to meet factory 
specs.  What I often wonder is in this era of JJA's why has no one built a 
better reference like has been done with Quartz oscillators for many decades? 
Cheers;
Thomas Knox


> From: wpgold3...@att.net
> To: volt-nuts@febo.com
> Date: Tue, 27 Jan 2015 08:20:50 -0800
> Subject: Re: [volt-nuts] 3458A reference boards on ebay
> 
> 
> - Original Message - 
> From: "Dr. David Kirkby (Kirkby Microwave Ltd)"
> 
> To: "Discussion of precise voltage measurement" 
> Sent: Tuesday, January 27, 2015 2:24 AM
> Subject: Re: [volt-nuts] 3458A reference boards on ebay
> 
> 
> > On 27 January 2015 at 09:16, Orin Eman  wrote:
> > > There is a seller letting a slow trickle of them out there... they seem
> to
> > > be going for about $165.  The current batch of two is around $100, but
> will
> > > probably be bid up.
> > >
> > > I just received one that I won.  Seems to be working fine after a quick
> > > breadboard lashup.  I'll be making an enclosure for it next.
> > >
> > > A little expensive IMO, but given the trouble getting the precision
> > > resistors to DIY with the LTZ1000A, probably worth it.
> > >
> > > Orin
> >
> > Orin,
> >
> > What do you intend doing with it?
> >
> > I was thinking about getting one of those, with a view to putting it
> > in a box with a couple of terminals to have something to compare with
> > my 6.5 digit 3457A.  But what put me off is a lack of knowledge in
> > knowing how to convert a 3458A reference board into a boxed unit with
> > a known output voltage at the terminals. How would I avoid / control
> > thermal EMFs?
> >
> > I'd be interested to hear what your plans are for it, and how you
> > intend tackling those issues.
> >
> > Do you know what the difference in the reference is between a standard
> > 3458A (8 ppm) and the high stability option 002 (4 ppm) model? I'm
> > guessing the chips for the option 002 might be the top performing
> > ones. I wonder if there's any way to tell from your board if it came
> > from a standard 3458A or a 3458A with option 002.
> >
> > Dave
> 
> Dave:
> 
> The 002 reference boards have another label on them marked 03458-66519
> which overlays the etched number on the PC board.  As a matter of fact see
> the new listing on evilbay 271754789913.  The super ultra stable 2ppm is
> marked 03458-66529 to the best of my knowledge.
> 
> Bill
> 
> > ___
> > 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.
  
___
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.

Re: [volt-nuts] Voltage standard spotted for sale, 4410

[Tom Knox]

I am not sure the use of LM329's was a cost saving measure or compromise, 
actually the 4410 uses a different approch, it's basicly is a big oven. 
Guildline has been a Metrology leader for decades and  has been a leader 
including  temp measurements and oil baths so I for one would be interested in 
how well their approach to a voltage standard performs.
Cheers;
Thomas Knox



> Date: Mon, 11 Aug 2014 22:24:57 +0300
> From: willvo...@gmail.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] Voltage standard spotted for sale, 4410
> 
> > Comparable to the Datron 4911.
> 
> The 4410 is based on ovenised LM329 reference = LM399 without a
> heater. You can expect drift by factor of 10 worse than Datron
> 4910/4911 or a good Fluke 732A.
> ___
> 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.

Re: [volt-nuts] Matched resistors

[Tom Knox]

Hi Randy;
I would look at Visha Foil resistors
http://www.vishaypg.com/docs/63120/hzseries.pdf
Hope that helps.
Cheers;
Thomas Knox



> Date: Wed, 16 Jul 2014 17:44:10 -0700
> From: randyevans2...@gmail.com
> To: volt-nuts@febo.com
> Subject: [volt-nuts] Matched resistors
> 
> I am building a 10V voltage reference based on the LTZ1000 and the design
> is essentially done but I am looking for a pair of matched resistors that
> track very closely over temperature.  The absolute value of the pair is not
> important, anything between 50K and 200K ohms would be ideal, but the
> matching ratio is very important.
> 
>  I looked at the 100K ohm LT5400 quad resistor array from Linear Technology
> but it has a worst case long term accelerated shelf life spec of 10 ppm (at
> 150C) matching ratio and long term matching ratio drift of <4ppm (at 70C).
>  I would like something much tighter if possible since that would mean I
> likely don't need an oven for a couple of ppm worst case accuracy over time
> and temperature.  I can make the LT5400 work but I would need to do
> temperature characterization and circuit compensation.  Doable but
> undesirable.
> 
> Does anyone have any ideas for a good ratio matched resistor pair,
> hopefully not too expensive?
> 
> Thanks,
> 
> Randy Evans
> ___
> 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.

Re: [volt-nuts] Desperately seeking OPTION 10 for Datron 4708

[Tom Knox]

I wonder if the tolerances are different on option 10 boards in the series? If 
so it could makes the board much easier to find. The service manuals would 
confirm interchangeability if the part numbers are the same, but even if the 
4708 uses selected parts, most components stability improve with age and so if 
the topography is the same you should be good to go.

Thomas Knox


Luck is preparation waiting to happen. 

> From: tmical...@gmail.com
> Date: Wed, 16 Jul 2014 10:29:43 -0400
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] Desperately seeking OPTION 10 for Datron 4708
> 
> Chris,
> 
> I believe the current and resistance functions are on the same board. My 4700 
> is missing one board and it has both missing features.
> 
> Todd
> 
> Sent from my iPad
> 
> > On Jul 16, 2014, at 8:48, Chris  wrote:
> > 
> > Thank you for the bad news :( I am starting to come to terms with the
> > difficulty of finding this option. I have recently discovered that option
> > 10 from the 4700, 4705, and 4707 would also work. Not sure if this makes it
> > any easier.
> > 
> > Also my unit has a sticker on the front indicating "ac voltage and current
> > only"... But lists options 20,30,80,90 on the backside label. Will my unit
> > have resistance functionality? I am hearing a lot of conflicting
> > information.
> > 
> > Not sure if I am replying to emails correctly. (New to volt nuts)
> >> On Jul 12, 2014 6:03 PM, "Chris"  wrote:
> >> 
> >> Nobody has access to spare Datron 4708 stuff? I am willing to pay
> >> international shipping etc... whatever it takes! Thank you
> >> 
> >> 
> >>> On Thu, Jul 10, 2014 at 2:09 PM, Chris  wrote:
> >>> 
> >>> I am looking to purchase OPTION 10 slide in board for the Datron 4708
> >>> Multifunction Calibrator. If anybody has a parted out unit and can sell me
> >>> just the option 10 board i would appreciate it dearly! Thank you for
> >>> considering!
> >>> 
> >>> Chris
> > ___
> > 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.
  
___
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.

Re: [volt-nuts] Desperately seeking OPTION 10 for Datron 4708

[Tom Knox]

Hi Chris;
Sorry to be the bearer of bad news, Do you have any idea how many 4708's were 
built and sold as AC standards, my guess it the number is much, much greater 
then fully loaded and DC only units combined. Point being you will be very 
lucky if someone is willing to part with option 10, and if so they will most 
likely want much more then you paid for the calibrator since I have seen 4708 
AC standard sells for a few hundred dollars ,and a fully loaded 4708 still 
commands more then five grand. 

Thomas Knox



> From: caal...@gmail.com
> Date: Sat, 12 Jul 2014 19:03:53 -0400
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] Desperately seeking OPTION 10 for Datron 4708
> 
> Nobody has access to spare Datron 4708 stuff? I am willing to pay
> international shipping etc... whatever it takes! Thank you
> 
> 
> On Thu, Jul 10, 2014 at 2:09 PM, Chris  wrote:
> 
> > I am looking to purchase OPTION 10 slide in board for the Datron 4708
> > Multifunction Calibrator. If anybody has a parted out unit and can sell me
> > just the option 10 board i would appreciate it dearly! Thank you for
> > considering!
> >
> > Chris
> >
> ___
> 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.

Re: [volt-nuts] AC Voltage Measurement Standards

[Tom Knox]

The ultimate AC standard would be NIST's AC Josephson junction array. Sam Benz 
and his team continue to make advances, pushing the accuracy and output level. 
They have also substantially reduced the needed electronics placing much of the 
peripheral electronics in a custom built two-U enclosure. NIST has also 
recently introduced a fully programmable JJA that automates most of the set up 
and operation. It won't be long before we need 10 1/2 digit DMM's 
Cheers;
Thomas Knox



> From: acb...@gmx.de
> To: volt-nuts@febo.com
> Date: Fri, 11 Jul 2014 01:13:44 +0200
> Subject: Re: [volt-nuts] AC Voltage Measurement Standards
> 
> in a nutshell, what i am doing is that I first establish the dc (+/-) output 
> of the ref. TVC at nominal and then determine the ac voltage from a 
> precision, highly linear (datron 4808) ac source that generates that default 
> output voltage at the key frequencies. that establishes a set of ac voltage 
> settings. for these the deviations of the TVC are known from the calibration. 
> then I do the same with the TVC to be calibrated. (factor of 2 nom. voltage 
> is important to stay within allowable range). that way you can link both.
> sure, sending all to cal is more precise, if you get the right lab at least, 
> but also very expensive.
> 
> would sure be interested in your tech paper
> 
> 
> 
> > Gesendet: Donnerstag, 10. Juli 2014 um 13:27 Uhr
> > Von: "Stephen Grady" 
> > An: "'Discussion of precise voltage measurement'" 
> > Betreff: Re: [volt-nuts] AC Voltage Measurement Standards
> >
> > Todd and anyone else would is interested,
> > 
> > Measuring a Thermal Converter against another Thermal Converter is a bit of
> > a black art. The main problem is thermal converters are a square law device
> > that is if you change the input voltage by a factor of 2 the output voltage
> > will change by a factor of approximately 4. Now I say approximately because
> > for most thermal converters like the Fluke 540B, A55, Ballantine and Holts
> > the actual factor can be anywhere from 1.4 to 1.8 due to losses in the
> > thermal converter. In the literature you often see this factor refer to as
> > the N factors. Each thermal converter will have its own N factor which must
> > be measured to make sense of the measurements.
> > 
> > It even becomes more difficult in that the AC-DC difference of a thermal
> > converter is defined as (Vac-Vdc)/Vdc where Vac and Vdc are the inputs to a
> > thermal converter which give an equal output from the converter. Also Vdc is
> > the mean of the forward and reverse DC voltages. The problem is that when
> > you have two converters connected in parallel you cannot balance both
> > converters AC and DC inputs to produce equal voltage out of the converters
> > at the same time because each converter has its own AC-DC difference and its
> > own N factor.
> > 
> > It anyone is interested I can send them a technical paper that describes
> > this process and the appropriate math to use but I cannot send it to the
> > list due to copyright issues.
> > 
> > Kind Regards,
> > 
> > Stephen Grady
> > Sydney Australia
> > 
> > 
> > -Original Message-
> > From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On
> > Behalf Of Todd Micallef
> > Sent: Thursday, 10 July 2014 2:36 AM
> > To: Discussion of precise voltage measurement
> > Subject: Re: [volt-nuts] AC Voltage Measurement Standards
> > 
> > I would like to know more about your setup. Which source(s) are you using
> > for the input and which nanovoltmeter(s) are you using to transfer the 10V
> > TVC to your other converters? I remember you asking on PMEL forum about the
> > accuracy of using a 34420A nanovoltmeter. I did not see a response as to
> > whether you opted for an alternative like Keithley 2182(A) or a low noise
> > preamplifier connected to a 3458A.
> > 
> > I have done some reading about how NIST transfers their calibrations using
> > two TVC's in parallel and I am guessing that is what you are doing.
> > 
> > http://www.nist.gov/pml/div684/acdc/tcs.cfm
> > 
> > To transfer the accuracy up/down to other TVC's at different rated voltages
> > appears to be a difficult task since they typically need at least half the
> > rated max voltage to be within spec. It would be similar to starting with a
> > SR104 standard and transferring its value through a set of SR1010 and
> > SR1050 resistors using an ESI 242.
> > 
> > I have a few AC sources, and I would like to be able to verify my TVC's
> > without sending all of them out for cal. Ballantine quoted $600+ per TVC and
> > I haven't checked what Fluke would charge for each A55.
> > 
> > Todd
> > 
> > 
> > I personally did the following: I got a Ballantine 1605A transfer
> > > voltmeter. This is comparable to the 792A in a way, except it was much 
> > > cheaper. It is automatic, much easier to use than the Fluke 540 and 
> > > goes up to I think 100MHz. This can be used for percision calibrations 
> > > as a working standard. The calib

Re: [volt-nuts] Buying HP-3458A

[Tom Knox]

Be careful, Agilent's standard service is not that simple. 

Thomas Knox



> Date: Sat, 5 Jul 2014 16:08:26 -0700
> From: randyevans2...@gmail.com
> To: volt-nuts@febo.com
> Subject: [volt-nuts] Buying HP-3458A
> 
> I am in the market for a used HP-3458A and, in researching past messages, I
> came across an interesting question:
> 
> *Chris Erickson* ericksonc2 at comcast.net
> 
> *Thu Sep 22 19:48:41 UTC 2011*
> 
> If Agilent will fix everything, bring it up to specs, and calibrate it no
> 
> matter what's wrong with it for $2200, then why would I spend $5000-6000 or
> 
> more for one that is in good shape - even if calibrated? Just grab the first
> 
> bargain that comes along for $1500-3000, send it straight to Agilent and be
> 
> money ahead. Seems the better course of action to me if that price is
> 
> accurate - do they really offer this service?
> 
> 
> 
> 
> I could not find an answer to this question but it does beg the question.
>  Does nayone have an answer as to why not buy the cheapest unit and send it
> in for repair?
> 
> 
> Thanks,
> 
> 
> Randy Evans
> ___
> 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.

Re: [volt-nuts] 732b transformer replacement

[Tom Knox]

I would first attempt to purchase a OEM replacement from Fluke. You never know 
it may be reasonably priced.  
Cheers;
Thomas Knox



> Date: Wed, 4 Jun 2014 17:16:37 -0400
> From: pit...@williams-net.com
> To: volt-nuts@febo.com
> Subject: [volt-nuts] 732b transformer replacement
> 
> My 732b is fine but its transformer bit the dust before I got it.
> 
> Actually, that's probably WHY I got it on fleabay.. its previous
> owner changed the battery and still couldn't get it to charge!
> So it went on fleabay as 'parts/not working'..
> for a price I could afford!
> 
> The primary is cooked. Using a fresh battery powers the standard,
> though, with a solid 9.9 volts on my junk 3458 for two months.
> 
> I just want a transformer for 120V... don't need all the world's
> voltages. Since it probably won't be guarded, I would unplug the
> 732 and go on battery to do readouts to avoid powerline crosstalk
> problems.
> 
>   The best of all worlds would be to get the exact, correct transformer.
> 
> Willy
> ___
> 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.

Re: [volt-nuts] what in transfer accuracy

[Tom Knox]

Isn't short term stability usually rated at 24 hours? I would think transfer 
accuracy (although perhaps not formally defined as a Metrology term) is more in 
minutes or second which would be important when you compare something like your 
JJA against your 732B. It would also be pretty obvious since you could repeat 
the process repeatedly to eliminate uncertainty.
Cheers;
Thomas Knox



> Date: Tue, 13 May 2014 18:25:33 +0200
> From: j...@41hz.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] what in transfer accuracy
> 
> Not sure if I already posted this:
> 
> From the replies, it seems "Transfer Accuracy" is not really defined, open
> for interpretations. It is perhaps not very important either, as short term
> stability is usually specified.
> ___
> 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.

Re: [volt-nuts] Datron 1082

[Tom Knox]

Sorry I wasn't clear. I think the errors you are experiencing are because the 
memory battery is gone, so it won't matter now, this is for saving the cal data 
during future replacement to avoid these problems again.
Best Wishes;
Thomas Knox



> Date: Mon, 21 Apr 2014 19:59:29 -0700
> From: randyevans2...@gmail.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] Datron 1082
> 
> Tom,
> 
> I would think with 0.08 VDC the battery is dead and all the memory is gone.
>  Do you think it would make any difference if I paralleled the leads with a
> new one?  I don't have a parts list to know what type the battery is so
> it's going to be a challenge to find a direct replacement.  Wish I had a
> manual.
> 
> Randy
> 
> 
> On Mon, Apr 21, 2014 at 7:54 PM, Tom Knox  wrote:
> 
> > Randy I would say from my experience with Datron there is about 90% chance
> > the battery and recal will solve the problem. I would modify the battery
> > with a coupe sets of leads that are long enough so you can install a new
> > while the old battery is still in circuit.
> > Best Wishes;
> > Thomas Knox
> >
> >
> >
> > > Date: Mon, 21 Apr 2014 19:23:35 -0700
> > > From: randyevans2...@gmail.com
> > > To: volt-nuts@febo.com
> > > Subject: Re: [volt-nuts] Datron 1082
> > >
> > > I believe the voltages are correct but I have no schematics or
> > > troubleshooting instructions to confirm.  I do see what looks like a
> > > battery in the memory section of the 1082 and it measures 0.08 VDC. Not a
> > > good sign.  I am really hoping someone has a Datron 1082 Service manual
> > > with schematics that they can steer me to, preferably a soft copy so I
> > can
> > > better troubleshoot the unit.  It might just need a new battery (plus a
> > > re-cal) to get it going again but I hate going blind.
> > >
> > > Randy
> > >
> > >
> > > On Mon, Apr 21, 2014 at 8:15 AM, Tom Knox  wrote:
> > >
> > > > As with many products of this age the tantalum caps are a common point
> > of
> > > > failure in the 1082.
> > > > Although this current problem sounds like a memory battery.
> > > >
> > > > Thomas Knox
> > > >
> > > >
> > > >
> > > > > Date: Mon, 21 Apr 2014 11:03:56 -0400
> > > > > From: cfhar...@erols.com
> > > > > To: volt-nuts@febo.com
> > > > > Subject: Re: [volt-nuts] Datron 1082
> > > > >
> > > > > Just in case you haven't yet: Always start any investigation with
> > > > > checking the power supply for voltage and ripple.  Test the main
> > > > > electrolytic capacitors for capacitance, and ESR.
> > > > >
> > > > > Nothing in the unit's self testing ability can be trusted if the
> > > > > power supply is putting out large amounts of ripple, or is at the
> > > > > wrong voltage.
> > > > >
> > > > > -Chuck Harris
> > > > >
> > > > > Randy Evans wrote:
> > > > > > I have a Datron 1082 DMM that just recently stopped working.  When
> > I
> > > > power
> > > > > > up, it gives a "FAIL" message on the front panel.  I found a
> > flowchart
> > > > in
> > > > > > an abbreviated servicing manual that indicates it's from a failure
> > of
> > > > the
> > > > > > "Check for uncorrupted calibration store".  I Assume this likely
> > means
> > > > the
> > > > > > cal tables are corrupted?  Unfortunately, I don't have sufficient
> > > > > > information (e.g., schematics) to do any further troubleshooting.
> >  Can
> > > > > > anyone help with a complete servicing manual and/or further
> > diagnostic
> > > > help?
> > > > > >
> > > > > >
> > > > > > I did download the Datron 1071DMM  O&S manual from K04BB but I
> > don't
> > > > know
> > > > > > how similar it is to the 1082.  Can anyone comment on what the
> > > > differences
> > > > > > are?
> > > > > >
> > > > > >
> > > > > >
> > > > > > Thanks,
> > > > > >
> > > > > >
> > > > > >
> > > > > > Randy Evans
> > > > >

Re: [volt-nuts] Datron 1082

[Tom Knox]

Randy I would say from my experience with Datron there is about 90% chance the 
battery and recal will solve the problem. I would modify the battery with a 
coupe sets of leads that are long enough so you can install a new while the old 
battery is still in circuit.
Best Wishes;
Thomas Knox



> Date: Mon, 21 Apr 2014 19:23:35 -0700
> From: randyevans2...@gmail.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] Datron 1082
> 
> I believe the voltages are correct but I have no schematics or
> troubleshooting instructions to confirm.  I do see what looks like a
> battery in the memory section of the 1082 and it measures 0.08 VDC. Not a
> good sign.  I am really hoping someone has a Datron 1082 Service manual
> with schematics that they can steer me to, preferably a soft copy so I can
> better troubleshoot the unit.  It might just need a new battery (plus a
> re-cal) to get it going again but I hate going blind.
> 
> Randy
> 
> 
> On Mon, Apr 21, 2014 at 8:15 AM, Tom Knox  wrote:
> 
> > As with many products of this age the tantalum caps are a common point of
> > failure in the 1082.
> > Although this current problem sounds like a memory battery.
> >
> > Thomas Knox
> >
> >
> >
> > > Date: Mon, 21 Apr 2014 11:03:56 -0400
> > > From: cfhar...@erols.com
> > > To: volt-nuts@febo.com
> > > Subject: Re: [volt-nuts] Datron 1082
> > >
> > > Just in case you haven't yet: Always start any investigation with
> > > checking the power supply for voltage and ripple.  Test the main
> > > electrolytic capacitors for capacitance, and ESR.
> > >
> > > Nothing in the unit's self testing ability can be trusted if the
> > > power supply is putting out large amounts of ripple, or is at the
> > > wrong voltage.
> > >
> > > -Chuck Harris
> > >
> > > Randy Evans wrote:
> > > > I have a Datron 1082 DMM that just recently stopped working.  When I
> > power
> > > > up, it gives a "FAIL" message on the front panel.  I found a flowchart
> > in
> > > > an abbreviated servicing manual that indicates it's from a failure of
> > the
> > > > "Check for uncorrupted calibration store".  I Assume this likely means
> > the
> > > > cal tables are corrupted?  Unfortunately, I don't have sufficient
> > > > information (e.g., schematics) to do any further troubleshooting.  Can
> > > > anyone help with a complete servicing manual and/or further diagnostic
> > help?
> > > >
> > > >
> > > > I did download the Datron 1071DMM  O&S manual from K04BB but I don't
> > know
> > > > how similar it is to the 1082.  Can anyone comment on what the
> > differences
> > > > are?
> > > >
> > > >
> > > >
> > > > Thanks,
> > > >
> > > >
> > > >
> > > > Randy Evans
> > > ___
> > > 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.
> >
> ___
> 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.

Re: [volt-nuts] Datron 1082

[Tom Knox]

As with many products of this age the tantalum caps are a common point of 
failure in the 1082.
Although this current problem sounds like a memory battery.

Thomas Knox



> Date: Mon, 21 Apr 2014 11:03:56 -0400
> From: cfhar...@erols.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] Datron 1082
> 
> Just in case you haven't yet: Always start any investigation with
> checking the power supply for voltage and ripple.  Test the main
> electrolytic capacitors for capacitance, and ESR.
> 
> Nothing in the unit's self testing ability can be trusted if the
> power supply is putting out large amounts of ripple, or is at the
> wrong voltage.
> 
> -Chuck Harris
> 
> Randy Evans wrote:
> > I have a Datron 1082 DMM that just recently stopped working.  When I power
> > up, it gives a "FAIL" message on the front panel.  I found a flowchart in
> > an abbreviated servicing manual that indicates it's from a failure of the
> > "Check for uncorrupted calibration store".  I Assume this likely means the
> > cal tables are corrupted?  Unfortunately, I don't have sufficient
> > information (e.g., schematics) to do any further troubleshooting.  Can
> > anyone help with a complete servicing manual and/or further diagnostic help?
> >
> >
> > I did download the Datron 1071DMM  O&S manual from K04BB but I don't know
> > how similar it is to the 1082.  Can anyone comment on what the differences
> > are?
> >
> >
> >
> > Thanks,
> >
> >
> >
> > Randy Evans
> ___
> 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.

Re: [volt-nuts] 3458a with 202: Slave Test Convergence (sigh)

[Tom Knox]

The dreaded 202 convergence error, If you need help contact me off list.
Best Wishes;

Thomas Knox



> From: pit...@williams-net.com
> To: volt-nuts@febo.com
> Date: Thu, 27 Mar 2014 14:35:42 -0400
> Subject: [volt-nuts] 3458a with 202: Slave Test Convergence (sigh)
> 
> I know that HP will (gladly?) take your sick 3458 and bring it up to current 
> specs, followed by a calibration. Since my sick one is at engineering level 2 
> or 3.something, it must be like it was built in 1989 - the dates on some 
> components.
> 
> Should I try to do any troubleshooting, or just send it to HP?  
> 
> Will they upgrade the current (aged and pretty much not drifting) boards?
> 
> Or do they take a good board from their stock and replace the current board 
> with one that may be new and 'drifty'?
> 
> I have read here that there are some unlisted upgrades that they do, also.
> 
> The RAM batteries will be replaced also, right? 
> 
> The biggest positive I see is the ability to go on the service plan and never 
> have to worry about a failure again after the 3458 is brought up to current 
> standards.
> 
> Willy
> ___
> 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.

Re: [volt-nuts] 3458a RAM batteries - longer life if unit is continually powered?

[Tom Knox]

Date Codes can be misleading because most of this style of chip does not 
connect to the battery until the first power up cycle. So evl

Thomas Knox



> Date: Thu, 27 Mar 2014 17:33:17 +0100
> From: frank.stellm...@freenet.de
> To: volt-nuts@febo.com
> Subject: [volt-nuts] 3458a RAM batteries - longer life if unit is 
> continually powered?
> 
> Hi,
> 
> the DALLAS datasheet specifies 10 years data retention. Quite obviously, 
> that's the unpowered time.
> 
> That time includes self discharge and RAM sustaining currents.
> 
> self discharge and RAM supply current will be of the same order, i.e. < 
> 1µA, I assume from experience.
> And I assume also, that those currents will vary over samples, i.e. over 
> samples of battery and RAM.
> 
> Recently, there was the case, where the CAL RAM was still alive after 24 
> years (instrument vintage 1989, same DALLAS date code!), but with 
> unknown powering history.
> 
> Additionally, a typical 10 years of lifetime is given also for those 
> batteries.
> 
> Therefore, in practise there will be no pronounced difference between 
> powered / unpowered state.
> On the other hand, DALLAS implemented an electronic seal, so that the 
> RAM inside the package is initially powered only after first power up. 
> But there's no parameter in the datasheet, specifying data retention 
> according to date code or to initial power up.
> 
> 
> The waste of energy just to extend the batteries lifetime, does not pay off.
> On the contrary, the MTBF time of the instrument will be consumed, the 
> display will get bad, and here in Germany, this energy consumption would 
> cost a fortune (meanwhile: 25+ Cents / kWh, crazy).
> 
> 
> Yes, as long the instrument is powered, the CAL RAM will not lose its 
> content.. but what about unexpected power outages?
> 
> 
> If you save the CAL RAM and repogram a fresh one after failure, there's 
> no need to send it to agilent.
> 
> 
> No, not any RAM error needs recalibration.
> Those error messages are not documented.
> 
> So I've scanned the text fragments in the firmware file:
> 
> RAM TEST 1
> RAM TEST 2
> 
> probably refer to either to the configuration RAMs (2x32kB), andthe CAL 
> RAM (8kB).
> 
> Eror messages are:
> NONVOLATILE RAM HiGH /LOW
> CAL RAM FAILURE
> 
> and known ones from other users:
> 
> RAM TEST 1 HIGH / LOW
> 
> So I assume, that a real failure of the cal constants only apply on 
> message: CAL RAM FAILURE and perhaps RAM TEST 2 , as RAM TEST 1 
> should refer to the configuration RAMs only, HIGH to the high byte RAM, 
> LOW to the low byte RAM.
> 
> Errors of the cal RAM will manifest in additional ACAL or CAL failures.
> 
> 
> Frank
> ___
> 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.

Re: [volt-nuts] Fluke 5100B Calibrator‏ Repair Help

[Tom Knox]

Someone will most likely have an exact value, but assuming that RV1 and RV2 are 
being used as excessive transient voltage protection another way to determine 
value is to use a variac to power up the 5100B and measure the normal voltages 
at RV1 and RV2. Then replace with a properly rated MOV. 

Thomas Knox



> From: w...@msn.com
> To: volt-nuts@febo.com
> Date: Thu, 13 Mar 2014 09:34:48 -0700
> Subject: [volt-nuts] Fluke 5100B Calibrator‏ Repair Help
> 
> I need some help with repairing a Fluke 5100B Calibrator. 
> The capacitor support bracket fell into the power supply module and vaporized 
> both varistors, RV1 and RV2. A call to Fluke tells me they no longer can 
> supply these MOV's. According to the manual's parts list these varistors are 
> in-house parts by Fluke. I have no way of determining a substitute part. Is 
> there anyone that can help me identify what could be a useful replacement?
> Thanks,
> Dave - W6TE 
> ___
> 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.

Re: [volt-nuts] A Fluke 732A

[Tom Knox]

Charles thanks for an engaging dialog, I think we generally agree, but have 
different interpretations of several words. I see calibration as a set of rules 
and procedures that a group has agreed upon, that when followed will allow 
tractability and repeatability to an agreed upon standard. And in our 
discussion I have considered documentation to to part of that strict set of 
rules. So if a guy has his friend at Fluke calibrate his 732A on the JJA over 
the weekend and does not file the correct paper work in my humble opinion no 
claim of calibration can be made. Calibration is what you can prove not what 
you know. But when that guy returns to his lab with the standard he knows if 
function correctly is will perform to a certain level. To me, in my lab; that 
is enough. Metrology is an important part of my life, and I wish I had the time 
and money to go through all the various levels of documentation and 
accreditation in my lab. Unfortunately it is just not practical. What I have 
done is c
 ollect multiple standards that I compare frequently one another in addition to 
comparing them to outside standards when I have the opportunity and if they all 
agree with-in the range of uncertainty I am fairly confident I can trust them 
in my work. But that is what I know, not what I can prove, therefore I never 
make claims any instrument worked on in my lab is calibrated with the exception 
of some Time and Freq equipment, but that is for another discussion. I will be 
interest to know what path Michael Hong goes with as to whether to return or 
keep the Fluke 732A and what route he chooses to follow concerning calibration. 
I hope the conversation has aided your decisions, please keep us posted.

Thomas Knox



> Date: Mon, 10 Mar 2014 08:33:01 -0400
> To: volt-nuts@febo.com
> From: csteinm...@yandex.com
> Subject: Re: [volt-nuts] A Fluke 732A
> 
> 
> >I have to side with Tom on this one. Accreditation only provides 
> >independant verifcation of processess and proceedures. It provides 
> >increased confidence (in both the human and statistical senses) in 
> >the service provided. It does not prove that your standard is correct.
> 
> Documentation and accreditation are two entirely different 
> things.  Documentation is keeping track of a quantified chain of 
> inference leading to a conclusion regarding the uncertainty of a 
> measurement.  If documentation has not been done, there is no basis 
> for ANY claim about the uncertainty of a measurement.
> 
> Accreditation is the process of evaluating and auditing someone's 
> procedures (including their documentation) by a third party.
> 
> Accreditation is not necessary to have a basis for a claim of the 
> bounds of uncertainty of a measurement, but documentation is.
> 
> Best regards,
> 
> Charles
> 
> 
> 
> ___
> 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.

Re: [volt-nuts] A Fluke 732A

[Tom Knox]

Charles is difficult to disagree you are simply explaining the system that has 
evolved over decades that insures the accuracy of our standards labs, and I 
have found I am barely smart enough to get coffee for some of the Senior Time 
and Volt Nuts members. You have made your point very eloquently and I don't 
necessarily disagree with anything you say. But I feel reading your response I 
have failed to make my point.
I will make one last effort using a example. 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, but 
you can be confident yours is correct and You have save nearly $1000 dollars. 
There is what you can prove, but there is also what you know using common 
sense. Many Volt-Nuts also work in Metrology or know someone who does. In my 
work these days solutions at the cutting edge of Metrology are often as much 
art as science. That intuition often leads to advances that are both 
document-able and repeatable. So as I brought up earlier if Volt-Nuts compared
  standards and shared data locally they could build there own model and 
uncertainty algorithm that although not recognized by accrediting bodies could 
achieve similar results.  If you can afford to fully document the instruments 
in you lab I encourage you to do so and support the industry, but that can be 
beyond the budget of even some serious researchers and exploring alternatives 
seems to be what the Volt-Nuts are all about. Also I have been collecting data 
for a number of years hoping I can find time to do a serious study showing the 
effects of shipping on calibration. And I can tell you my early data points 
toward the fact that a substantial part of the yearly uncertainty happens 
during shipping. I am also convinvced that in that next decade instruments will 
include an environmental sensor package, and cal will be based more on 
environmental expose then simple time. As Physicists have pushed the limits of 
Metrology in recent years there has been little research in insuring these
  improved accuracies reach the end user. Expect changes in coming years.

Thomas Knox



> Date: Sun, 9 Mar 2014 04:18:07 -0400
> To: volt-nuts@febo.com
> From: csteinm...@yandex.com
> Subject: Re: [volt-nuts] A Fluke 732A
> 
> Thomas wrote:
> 
> >You may find a local lab with less accreditation charging half then 
> >price that is fully capable of of calibrating to the limit of the 
> >732A but cannot document to the level of a primary standards lab.
> 
> Very, very doubtful.  Very few cal labs have a 732A or equivalent, 
> much less anything better.  The only labs with *better* uncertainty 
> than a properly working 732A are those with JJAs.  If you look at the 
> NIST NVLAP accreditation list and run down it, looking at each lab's 
> "Scope of Accreditation," you will only find 4 or 5 labs on the list 
> with better uncertainty than a properly working 732A (I'm not sure 
> you will find *any* on the A2LA accreditation list, but I haven't run 
> down it lately).  The Fluke cal lab and the Los Alamos and Sandia 
> standards labs are three of those four or five (plus, of course, NIST 
> itself).  Boeing (Seattle) is another.  Interestingly, you will find 
> many labs that are rigorously accredited to only .003% or so (30 
> ppm), because the best voltage standard they own is an HP 34401A 
> DMM.  Even the HP Houston cal lab is certified to only 0.0007%, or 7 
> ppm (using a Fluke 5700A calibrator).
> 
> >Yes a 1-2PPM Cals is not as sexy as a .1PPM Cal but in the real 
> >world the results when used in you home lab my be the same.
> 
> To get a calibration with an uncertainty of 1 or 2 ppm, the lab would 
> need, at a minimum, a 732A or 732B to compare with (as well as a 720A 
> Kelvin-Varley bridge, or equivalent, and a null meter that can 
> reliably be read to 0.1uV, if you want the calibration certified to 1 
> or 2 ppm at voltages other than 10v).  I don't think there are even 
> ten labs on the NVLAP list that claim to have a 732A or B (the 
> equipment used is often listed in the "remarks" column).
> 
> It does not take long to run down the whole list -- it's a short list 
> and the "Scope of Accreditation" documents load fast.  I recommend 
> the exercise, to get a feel for what's out there.  Same with the A2LA 
> list, but it is longer and not as well organized and it usually takes 
> 2 or 3 steps (running off to the lab's site) to get to the "Scope of 
> Accreditation."  (If you look at A2LA labs, pay attention to the lab 
> class and only look at "open" commercial labs -- the non-commercial 
> ones

Re: [volt-nuts] A Fluke 732A

[Tom Knox]

Hi Charles;
Perhaps you are correct. I work in the research area of metrology. I just 
assumed a number of labs have multi-cell standards like the Wavetek 4910 or 
Fluke 7010s or 734A and if recently cal'ed they should be more then capable of 
calibrating a 732A for home use. True the documentation is not there but does 
that matter in a majority of Volt-Nut applications. And if you ship VS local 
calibration you may have documentation stating lower uncertainty, but a local 
cal may actually be more accurate.  I also think the number of JJA's is larger 
then most think. Just this week a couple labs added 10 Volt Programmable 
Josephson voltage standards capable of producing AC and DC voltages. 
http://www.wmi.badw.de/teaching/Lecturenotes/AS/AS2013_Chapter6_Slides.pdf  
Again my point is do you need the documentation, and if not there are 
alternatives. Especially in a non temperature and humidity controlled 
environment that will affect both your standards and DUT. Don't get me wrong I 
am all about documentation and repeatability but not everyone needs or has the 
$300,000+ for a 10 Volt Programmable Josephson voltage standard. Again I float 
the idea of Volt-Nuts creating their own network to compare standards locally 
after a recent calibration.


Thomas Knox



> Date: Sun, 9 Mar 2014 04:18:07 -0400
> To: volt-nuts@febo.com
> From: csteinm...@yandex.com
> Subject: Re: [volt-nuts] A Fluke 732A
> 
> Thomas wrote:
> 
> >You may find a local lab with less accreditation charging half then 
> >price that is fully capable of of calibrating to the limit of the 
> >732A but cannot document to the level of a primary standards lab.
> 
> Very, very doubtful.  Very few cal labs have a 732A or equivalent, 
> much less anything better.  The only labs with *better* uncertainty 
> than a properly working 732A are those with JJAs.  If you look at the 
> NIST NVLAP accreditation list and run down it, looking at each lab's 
> "Scope of Accreditation," you will only find 4 or 5 labs on the list 
> with better uncertainty than a properly working 732A (I'm not sure 
> you will find *any* on the A2LA accreditation list, but I haven't run 
> down it lately).  The Fluke cal lab and the Los Alamos and Sandia 
> standards labs are three of those four or five (plus, of course, NIST 
> itself).  Boeing (Seattle) is another.  Interestingly, you will find 
> many labs that are rigorously accredited to only .003% or so (30 
> ppm), because the best voltage standard they own is an HP 34401A 
> DMM.  Even the HP Houston cal lab is certified to only 0.0007%, or 7 
> ppm (using a Fluke 5700A calibrator).
> 
> >Yes a 1-2PPM Cals is not as sexy as a .1PPM Cal but in the real 
> >world the results when used in you home lab my be the same.
> 
> To get a calibration with an uncertainty of 1 or 2 ppm, the lab would 
> need, at a minimum, a 732A or 732B to compare with (as well as a 720A 
> Kelvin-Varley bridge, or equivalent, and a null meter that can 
> reliably be read to 0.1uV, if you want the calibration certified to 1 
> or 2 ppm at voltages other than 10v).  I don't think there are even 
> ten labs on the NVLAP list that claim to have a 732A or B (the 
> equipment used is often listed in the "remarks" column).
> 
> It does not take long to run down the whole list -- it's a short list 
> and the "Scope of Accreditation" documents load fast.  I recommend 
> the exercise, to get a feel for what's out there.  Same with the A2LA 
> list, but it is longer and not as well organized and it usually takes 
> 2 or 3 steps (running off to the lab's site) to get to the "Scope of 
> Accreditation."  (If you look at A2LA labs, pay attention to the lab 
> class and only look at "open" commercial labs -- the non-commercial 
> ones do not take in third-party calibration work.)
> 
> A list of NVLAP-accredited labs can be found here:
> 
> 
> 
> There seems to be this myth of cal labs that can do just as good a 
> job as the expensive, accredited labs, but don't bother with 
> accreditation so they are much cheaper.  First, note that to do a job 
> as good as an expensive, accredited lab, any lab would have to do the 
> same documentation as the accredited lab.  If there is no 
> documentation, there can be no claim as to the calibration's 
> uncertainty.  Having done the documentation, which is the 
> time-consuming (thus, expensive) part, no commercial cal lab is going 
> to do without the accreditation (which is nothing but an audit of the 
> lab's procedures and documentation).  I stress again -- if there is 
> no documentation, there can be no claim as to the uncertainty of a 
> lab's work.  And since the documentation is the part that contributes 
> most to the cost, there simply are not any commercial labs that can 
> claim to have uncertainties on par with accredited cal labs, but are 
> not themselves accredited.
> 
> Best regards,
> 
> Charles
> 
> 
> 
> ___

Re: [volt-nuts] A Fluke 732A

[Tom Knox]

Good points Dick. A good question to ask yourself is what level of 
documentation do you really need? And what is the cost per PPM. You may find a 
local lab with less accreditation charging half then price that is fully 
capable of of calibrating to the limit of the 732A but cannot document to the 
level of a primary standards lab. Add to that the fact that the 732A cal'ed 
locally would not be subject to the abuse of shipping and the calibration on 
you bench may exceed that of a NIST JJA cal. Yes a 1-2PPM Cals is not as sexy 
as a .1PPM Cal but in the real world the results when used in you home lab my 
be the same.  
Just look at the effects of temp and humidity on calibration and you will see 
my point.`to yours.
Thomas Knox



> Date: Sat, 8 Mar 2014 17:17:53 -0800
> From: richiem5...@gmail.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] A Fluke 732A
> 
> Back to a few of the original issues. A big questionh would be just how 
> accurate the average volt nut needs the 732A to be? I once owned two 
> 732A, one working normally, and kept hot 24/7, and one that needed some 
> work with the charging circuits and new batteries. My 3458A being newly 
> cal'd at Agilent in Colorado Springs, I matched the two 732As to the 
> 3458A, then powered off the one with problems, worked on it off and on 
> over several weeks, then powered it back up. What I found was that the 
> one I worked on (after 48 hours warm-up) was within 0.2ppm of the hot 
> one and the 3458A. Over the next year, the drift got a little larger 
> among the three, but not by much -- a spread of about another 0.2ppm if 
> I remember right.
> 
> That's when I decided that since I wasn't going to try to be a standards 
> lab, shipping a 732A cold for cal was much easier and effective than 
> trying to do it hot, and I live about 30 air miles from Fluke in Everett.
> 
> Can you live with 1ppm uncertainty in your 732A? Some here obviously 
> can't, but I think many of us can and would be happy with that level of 
> accuracy -- certainly good enough to cal the various 6-1/2 digit meters 
> around, including the 3457 mentioned originally. And given my experience 
> of 732A stability, especially the good old ones that come on ebay and 
> the like, that 1ppm uncertainty is also a good check on the state of cal 
> of even the 8-1/2 digit boxes, which despite their resolution, are not 
> spec'd long-term for even 1ppm at 10V.
> 
> Best,
> Dick Moore
> ___
> 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.

Re: [volt-nuts] A Fluke 732A: Return it or keep it?

[Tom Knox]

I think everyone missed my point, Replace the current battery with ANY other 
type battery that is not destroyed by deep cyclng. Perhaps Ni-Mh would be 
better. Ni-Mh also has a very consistent output voltage (Low voltage drop) 
until nearly discharged. Also a quick Google search found a wealth of 
information on shipping Li-Ion and it appears the 732A batteries are right on 
the edge of no shipping restriction.

Thomas Knox



> Date: Sat, 8 Mar 2014 23:56:19 +
> From: vn...@toneh.demon.co.uk
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] A Fluke 732A: Return it or keep it?
> 
> Unfortunately the hazards are indeed very real. The regulations were 
> almost certainly introduced because a UPS cargo plane crashed in Dubai 
> in 2010, killing both crew, as a result of a catastrophic fire in the 
> cargo of 80,000 to 90,000 lithium batteries.
> 
> http://online.wsj.com/news/articles/SB10001424127887324110404578625801602671408
> 
> And surprise, surprise:
> 
> 'It added that shippers of some of the lithium battery cargo loaded onto 
> the plane in Hong Kong "did not properly declare these shipments" and 
> did not provide battery test reports recommended under U.N. aviation 
> guidelines.'
> 
> (Which may be of interest to those buying those AD584LH voltage 
> reference modules containing a lithium battery from Ebay).
> 
> And from
> 
> http://www.flyingmag.com/news/ups-747-crash-highlights-lithium-battery-danger
> 
> In a *recent report issued by the FAA in conjunction with Transport 
> Canada* , the agencies 
> predicted there will be an average of six cargo plane crashes between 
> now and 2021, with four of them likely to be caused by battery fires.
> Read more at 
> http://www.flyingmag.com/news/ups-747-crash-highlights-lithium-battery-danger#1FZYPdiLXxLz0Fby.99
> 'In a recent report issued by the FAA in conjunction with Transport 
> Canada, the agencies predicted there will be an average of six cargo 
> plane crashes between now and 2021, with four of them likely to be 
> caused by battery fires.'
> 
> Tony H
> 
> On 08/03/2014 22:32, Robert Atkinson wrote:
> > Hi David,
> > Our posts crossed. Note that the laptop battery has been independently 
> > safety tested. Or at least it should have been. Also you are no longer 
> > allowed to put batteries in you checked airline luggage, only carry-on and 
> > there are limits on the Lithium content (now expressed in WH to make it 
> > easier). This is pure safety addressing a very real hazard. The krytron 
> > restriction is ITAR (google it) as they are used to fire slapper detonators 
> > in nuclear weapons (that probably got a ping on a monitoring service;-).
> >
> > Robert G8RPI.
> >
> >
> >
> >
> > 
> >   From: David C. Partridge
> > To: 'Discussion of precise voltage measurement'  
> > Sent: Saturday, 8 March 2014, 22:04
> > Subject: Re: [volt-nuts] A Fluke 732A: Return it or keep it?
> >   
> >
> > You can ship a Li-Ion or Li-Po battery inside a laptop no problem, but not
> > on its own.
> >
> > No it doesn't make sense except to the postal/shipping/airline safety types.
> > Probably the same logic that applies to exporting krytrons (even though Made
> > in China applies to these too).anymore).
> >
> > Regards,
> > David Partridge
> > -Original Message-
> > From:volt-nuts-boun...@febo.com  [mailto:volt-nuts-boun...@febo.com] On
> > Behalf Of Chuck Harris
> >
> > Sent: 08 March 2014 21:36
> > To: Discussion of precise voltage measurement
> > Subject: Re: [volt-nuts] A Fluke 732A: Return it or keep it?
> >
> > Surely that isn't true... otherwise laptop computers and cell phones
> > wouldn't be allowed on board passenger aircraft.  A laptop computer's
> > battery would greatly exceed the power in the original 732A battery pack.
> >
> > -Chuck Harris
> >
> > ___
> > volt-nuts mailing list --volt-nuts@febo.com
> > To unsubscribe, go tohttps://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 tohttps://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.
  
___
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.

Re: [volt-nuts] A Fluke 732A: Return it or keep it?

[Tom Knox]

In my humble opinion your are best off first checking for a local Cal Lab with 
a Josephson Junction Array Voltage Standard.
You can then drop it off and pick it up your 732A. I would imagine the day of 
abuse during shipping has more effect on uncertainty then the rest of the year 
combined sitting in a controlled lab environment. And Speaking of Lab 
environments adding precise temp and humidity control will have a substantial 
effect on 732A and 3458A stability. Hooking a number of small electric heaters 
to PID controllers can provide even out room temperature.  Also I would almost 
always assume the 732A is more accurate then your 3458A even if you have the 
002 or HFL option. Has anyone attempted changing the battery technology to 
Li-Ion and redesigning the charger? I am sure you could get greatly improved 
battery life.

Thomas Knox



> From: jlt...@att.net
> To: volt-nuts@febo.com
> Date: Sat, 8 Mar 2014 07:50:55 -0600
> Subject: Re: [volt-nuts] A Fluke 732A: Return it or keep it?
> 
> Charles,
> 
> Thanks for the info on batteries.  I agree, some are definitely better than
> others.  However, I'm no 'connoisseur' of batteries yet.  The 732A I got was
> 'unknown working condition' and I wanted the cheapest batteries I could find
> to test the unit and see if I could get it up and running.  So far, it looks
> good.
> 
> Do you wind up having to re-solder some of the battery wires in the battery
> module in order to use the 12 V 5 AH batteries or will they just swing to
> the other side since it appears that the (+) and (-) terminals will wind up
> on the same side, instead of opposite sides with the 6 V 4.5 AH batteries?
> 
> I have not faced the shipping question yet, but, as David pointed out, there
> is an issue with shipping batteries.  I suspect it could be shipped but
> would be ground and, therefore, need a huge battery in order to get it to
> the other side of the country 'hot'.  I recall reading some thoughts on
> current drain for the unit when on batteries but I do not remember what it
> was.  Clearly, it should be at a minimum, and therefore the battery should
> last the longest, when already 'hot' when removed from AC power.  Has anyone
> done that experiment?  I live in NW FL and I am not aware of Cal Labs in my
> neighborhood that could do the work.  Atlanta, perhaps?  Does anyone have a
> recommendation of a capable Cal facility 'close by' to NW FL?
> 
> Short of sending it to Fluke or another facility, I will be limited to using
> my Agilent Cal'd 3458A to 'adjust' the 732A, then 'tracking' the 732A from
> year to year as the 3458A comes back from Cal.
> 
> I paid less than Michael and more than you for my unit but it seems to work.
> I have seen these sell on theBay for $450 and up.
> 
> Joe
> 
> 
> ___
> 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.

Re: [volt-nuts] JJA progress report

[Tom Knox]

The physics of a properly run JJA will always produce the same result so you do 
not need additional units for comparison.
That is the point of a world wide quantum voltage standard defined as K 
   J-90   = 483 597.9 
GHz/V . Just has the Hyperfine Transition of Cesium at 
about 9.192631770GHz is used to define the second. What is neat about the work 
NIST has done recently is that it has automated the System for ease of use and 
reduced the price to the point that it should see much wider use in day to day 
metrology.  Having your Agilent 3458A calibrated on a JJA may not yield much 
difference over a Fluke 5730A cal, but once the meter has been run a few years 
characterizing the A to D converter and 10VAC range would only need to be done 
once and could substantially improve performance. I personally think that the 
face of calibration will change in coming years, rather then simple time based 
cal periods, instruments will contain complex environmental sensor packages 
that will constantly monitor the instruments environment . S
 o calibration will be based more on the instruments exposure to extreme 
conditions then simple time. I bet the act of shipping has more effect on cal 
then years sitting in a lab. So if for example a 3458A was put in an 
environmental chamber on a shaker table I am sure we find that up to a certain 
point enviromental conditions would have little effect on cal but at some point 
would have a major effect. Once documented the cals would be based more on 
environmental exposure. In addition I am sure some environmental effects on cal 
are repeatable and could be documented so if monitored they could be 
compensated for extending time between cals. So in the future you would see 
your instrument display "environment conditions exceeded" "cal require", with 
perhaps even a display of currently instrument uncertainty.  This could change 
the face of calibration and become a multi-billion dollar industry.

Thomas Knox



> Date: Sun, 16 Feb 2014 07:06:18 -0700
> From: n...@npgcable.com
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] JJA progress report
> 
> 
> If Earth is subjected to a GRB strong enough to damage ground based 
> electronics,
> we are all going to have much more urgent problems than wondering if a JVS is
> operating properly.  Same for an EMP.  Lightning, however, might pose a more
> localized and serious threat.
> 
> Part of your training as an expert operator will include techniques to 
> dissuade
> various critters from considering the JVS for their burial ceremonies.
> 
> Carrying your best zener reference to the nearest facility with another JVS
> would be less expensive than buying and operating a second or third system.
> 
> Joe
> 
> 
> On 2/16/2014 12:58 AM, cheater00 . wrote:
> > How do you know the primary standard is not off? That is, how do you
> > know it's still "primary"? Maybe a gamma ray burst from a supernova
> > damaged some of the machinery inside, or a colony of crazy ants
> > crawled in and died inside.
> > 
> > D.
> > 
> > On Sat, Feb 15, 2014 at 10:10 PM, Joe Hobart  wrote:
> >>
> >> These devices are primary standards; you don't need three; you probably 
> >> don't
> >> even need two.  If certain conditions are met, conditions you can 
> >> check/verify,
> >> they will accurately generate the desired voltages.
> >>
> >> What you will probably want are at least three good zener type voltage 
> >> standards
> >> and a constant temperature environment.  The three will serve as a day to 
> >> day
> >> standard and reality check on the JJA.  And you need to really learn how to
> >> operate the JJA standard, so you can detect and correct any problems.
> >>
> >> Joe Hobart
> >> Flagstaff, Arizona
> >>
> >>
> >> On 2/15/2014 1:17 PM, Gordon DeWitte wrote:
> >>> Clearly need three (or some higher odd number) so they can vote...
> >>>
> >>> Gordon
> >>>
> >>>
> >>> On Sat, Feb 15, 2014 at 2:51 AM, Poul-Henning Kamp 
> >>> wrote:
> >>>
>  In message <1392413149.25851.yahoomail...@web142405.mail.bf1.yahoo.com>,
>  Randy
>  Evans writes:
> 
> > We'll all probably want a spare unit also.
> 
>  Two, how can you know which one fails, if you only have two ?
> 
>  --
>  Poul-Henning Kamp   | UNIX since Zilog Zeus 3.20
>  p...@freebsd.org | TCP/IP since RFC 956
>  FreeBSD committer   | BSD since 4.3-tahoe
>  Never attribute to malice what can adequately be explained by 
>  incompetence.
>  ___
> >>>
> ___
> 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 unsubscr

[volt-nuts] JJA progress report

[Tom Knox]

More progress has been made toward a plug and play Programmable Josephson 
Voltage Standard then I was aware of in some previous posts. Shortly NIST will 
begin selling Programmable Josephson Voltage Standard AC - DC standards that 
will have software to automatically calibrate (With-in the Arrays limit) 
products like the Agilent 3458A. This will include features like detailed 
characterizing the A-D converter linearity.  The price will be about 300K. So 
we are a great deal closer then I thought to Programmable Josephson Voltage 
Standard for every Volt-Nut.

Thomas Knox


  
___
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.

Re: [volt-nuts] Valhalla 2720GS

[Tom Knox]

BilI; I am sure you tried this, the model numbers are usually the default 
password. So try 2720 or Serial number or  or . 
The manual usually has a way to reset then password. For example the 3458A has 
a default password of 3458 and 2 jumpers one to hard lock the calibration and 
one to override and reset the password. 

Thomas Knox



> Date: Wed, 29 Jan 2014 13:06:27 -0500
> From: w...@quackers.net
> To: volt-nuts@febo.com
> Subject: [volt-nuts] Valhalla 2720GS
> 
> I've been searching far and wide trying to find out what the calibration 
> password is and how to use the hidden cal button.
> I know there was some discussion of 2720's and calibration a few years 
> ago here, but I haven't found anything covering the above.
> 
> If anyone knows, or has a link to the info, please let me know.
> 
> Thanks, Bill
> 
> -- 
> Bill Ezell
> 
> They said 'Windows or better'
> so I used Linux.
> 
> ___
> 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.

Re: [volt-nuts] Who bought a DT72A Dekatran Decade Transformer?

[Tom Knox]

I think the PRT73 would make a better volume control since the GPIB allows the 
potential of adding some type of wireless remote.

Thomas Knox



> Date: Mon, 27 Jan 2014 15:00:07 +0100
> From: j...@41hz.com
> To: volt-nuts@febo.com
> Subject: [volt-nuts] Who bought a DT72A Dekatran Decade Transformer?
> 
> Any voltnut bought one yesterday from Ebay?
> Looks like a nice box and a very decent price.
> Tell us more!
> 
> I'd like a pair as volume control for my stereo :-)
> ___
> 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.

Re: [volt-nuts] The 3458A A/D

[Tom Knox]

The Fluke 8508 is actually more of a Wavetek/Datron 1281 under the hood. The 
real difficulty in introducing a 3458A competitor is that the scientific 
community has been characterizing the HP meter for three decades. It's quarks 
and idiosyncrasies are well know such as how it will drift, or react to 
environmental changes.  Even a superiour meter will take years to be as usable. 

Thomas Knox



> From: john.philli...@gmail.com
> Date: Mon, 20 Jan 2014 15:33:39 -0800
> To: volt-nuts@febo.com
> Subject: Re: [volt-nuts] The 3458A A/D
> 
> The other reason the price is so high is that the cost of entry for a
> competitor to develop and sell a comparable unit for such low sales volume
> would also cost that much if not more. The Fluke 8508 does cost more but it
> is a 3458A "under the hood".
> 
> 
> On Mon, Jan 20, 2014 at 3:09 PM, Frank Stellmach  > wrote:
> 
> > "3. The 3458A still has got the best linear A/D, around 0.02ppm of input."
> >>>
> >>
> >  Is that a typo? Even 0.2 ppm would seem extremely good. I think I saw an
> >> official number of 0.1ppm somewhere. Probably 0.1ppm of range. And how do
> >> they implement that? Manual trimming and compensation?
> >>
> >
> > Hello Jan,
> >
> > well DNL, INL, sometimes I still struggle with those terms..
> >
> > Those 0.02ppm were nonlinearity of input, measured with a JJ array.
> > And they use a special multiple slope scheme, with glitch compensation for
> > the switching FETs.
> >
> > Just download the April 1989 HP Journal, there's everything explained in
> > detail.
> >
> > http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1989-04.pdf
> >
> >
> > Frank
> >
> >
> > ___
> > 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.
> >
> 
> 
> 
> -- 
> John Phillips
> ___
> 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.

Re: [volt-nuts] JJ standards and the 3458A

[Tom Knox]

As I said in an earlier post it does not require calibration, but set up and 
operation are beyond the difficulty of most equipments  calibration procedure. 
But great advances have been made as can be seen in Dave's quote below.
“The only problem with those (Past JJ's) is that they require an expert PhD 
physicist to operate,” Rudman says. “We wanted a standard that was 
considerably easier to use. If dissemination of the new, automated 
system proceeds as envisioned, then within our lifetimes there will no 
longer be a need for voltage transfer standards that have to be shipped 
off periodically for re-calibration. We can make primary standards, 
programmable from 0 to 10 volts, which are simple and cheap enough that 
every lab can have one. This is real now.” 
This "Now" you see in the photos is actually an AC JJ that will provide 
variable DC and AC signals.  
http://www.metas.ch/LesHouches/downloads/talks/16_Benz.pdf

http://www.nist.gov/pml/div686/devices/automated-voltage-standard-ready.cfm

Enjoy


Thomas Knox



> Date: Mon, 20 Jan 2014 08:00:57 +0100
> From: frank.stellm...@freenet.de
> To: volt-nuts@febo.com
> Subject: [volt-nuts] JJ standards and the 3458A
> 
> Hello,
> 
> JJ standards are always primary ones, i.e. don't need to be calibrated.
> 
> 
> Preconditiion is only, that the setup is deigned correctly, mainly that 
> the JJ voltage on cryongenic level is transferred to room temperature 
> level with high accuracy.
> 
> The JJ voltage is uncertain to 10e-17 on cryogenic level, i.e. on 
> comparing/transferring from one JJ to another by means of a SQUID.
> Transfer to RT is limited by thermal voltages to around 10e-9 uncertainty.
> 
> That's also the practical limit in the real, macroscopic world.
> 
> A 9.5 digit macroscopic or analogusly made DMM is unimaginable due to 
> following reasons:
> 1. Stability of Zener references are limited to around 0.1ppm in time, 
> temperature and noise
> 2. Same goes for the analogue range amplifiers, based on resistors.
> 3. The 3458A still has got the best linear A/D, around 0.02ppm of input.
> 4. Range transfer to the 5 Cardinal Points 1kV, 100V, 10V, 1V, 100mV is 
> also limited to around 0.2 - 0.5ppm (see Fluke 752A)
> 
> A JJ array could not be designed into an analogue DMM, due to the fact, 
> that the setup needs cryogenic devices as dewars, and lHe4 or lN2. 
> Microwave generator, frequency and constant current source can be made 
> compact, as there already exist "portable" JJ array setups for 
> comparison between primary labs. (Those comparisons always were precise 
> and limited to 10e-9 uncertainty).
> 
> Anyhow, as the Volt still is uncertain to about 2*10e-7 in the SI 
> system, a 9.5 digit DMM currently makes no sense at all.
> Let's see, if the BIPM will decide on the new SI by end of this year or 
> in 2 / 4 years only.
> 
> Then, I would propose to build a 9 digit DMM, but based exclusively on 
> cryogenic electronics, i.e. a JJ array as an ultra linear D/A and as a 
> primary Volt standard in one.
> 
> The only unsolved problem then would again be the range transfer, which 
> is not yet possible by cryogenic standards, afaik.
> 
> Similar limitations apply also to an quatum Ohm standrad / DMM, as the 
> Hall effect standard requires several Teslas of magnetic field, and 
> cryogenics, which cannot be built into an analoguos DMM, and also the 
> Ohm transfer to analogue resistors is again limited to 10e-9 by thermal 
> voltages.
> 
> Frank
> ___
> 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.

Re: [volt-nuts] What made a HP3458A so expensive

[Tom Knox]

A Josephson Junction is not a Cesium Standard. It is not quite to the Plug and 
Play level. And takes a few racks worth of space.
Operation and Maintenance is more difficult then most calibrations. But big 
advances are being made. 
At some point in the not to distant future I foresee JJ arrays being configured 
as not just a references,
but full function calibrators with direct quantum synthesis of any DC, AC, 
Ohms, and Current. Sam Benz
has lead much of this research. 
http://www.nist.gov/pml/div686/devices/voltage.cfm 
I am amazed that greater advances have not been made in zeners references or 
more specifically their packaging


Thomas Knox



> Date: Sat, 18 Jan 2014 17:44:43 -0700
> From: n...@npgcable.com
> To: tmiller11...@verizon.net; volt-nuts@febo.com
> Subject: Re: [volt-nuts] What made a HP3458A so expensive
> 
> Bill,
> 
> Would a Josephson Junction standard need to be calibrated?
> 
> Adjusted and maybe compared, yes, but you should not need to calibrate a 
> primary
> standard?  Years ago we had HP Cesium Frequency Standards at work.  There were
> primary standards and good to 4E-12 with no additional calibration.
> 
> Joe
> 
> 
> On 1/18/2014 3:37 PM, Tom Miller wrote:
> > Can you imagine what it would cost to get that calibrated?
> > 
> > Tom
> > - Original Message - From: "Bill Gold" 
> > To: "Discussion of precise voltage measurement" 
> > Sent: Saturday, January 18, 2014 5:17 PM
> > Subject: Re: [volt-nuts] What made a HP3458A so expensive
> > 
> > 
> > In fact if you look at a 1982 HP catalog you will see that the 3456A was
> > selling for around $3,700 and given inflation the 3458A is still a pretty
> > good bargain when it was introduced in 1989.  In 1989 the 3456A was selling
> > for $4,600 while the 3458A was selling for $5,900.  I wonder if there will
> > 
> > ever be a "3459A" 9.5 digit meter?  With a super miniture Josehpson Junction
> > for a reference?
> > Bill
> > 
> > - Original Message - From: "Tom Knox" 
> > To: "Discussion of precise voltage measurement" 
> > Sent: Saturday, January 18, 2014 1:29 PM
> > Subject: Re: [volt-nuts] What made a HP3458A so expensive
> > 
> > 
> > Actually in spite of it's high price I feel the 3458A represents a bargain.
> > When it was introduced in 1989 it was $5900. A price it held for decades.
> > Although designed in
> > then 80's it's accuracy is still unsurpassed.  The 8846A is much less
> > expensive because it has only about a quarter the parts. With few that
> > are hand selected and/or aged. And all though both meter have well
> > executed designs the result is the 3458A has about a magnitude greater
> > accuracy. And anyone in Metrology can attest to the fact that the cost
> > of accuracy is exponential. But the thought I wanted to contribute to the
> > dialog is the real value of the 3458A is the body
> > of knowledge built around the thousands of 358A's some running
> > continuously for nearly three decades. The characteristics of the 3458A
> > are perhaps the best documented of any electronic instrument ever made.
> > That is priceless. When comparing that body of knowledge to individual
> > units I have found every 3458A is a little different and seem to each
> > have their own personality. In a side note, recently I owned what appeared
> > 
> > to be the original 3458A. I cannot remember the serial number, but it had
> > the numbered stickers identifying the boards that can be seen in the
> > original service manual. And it was still  working flawlessly.
> > 
> > Thomas Knox
> > 
> > 
> > 
> >> Date: Sat, 18 Jan 2014 17:41:26 +0100
> >> From: frank.stellm...@freenet.de
> >> To: volt-nuts@febo.com
> >> Subject: [volt-nuts] What made a HP3458A so expensive
> >>
> >> Well,
> >>
> >> the 3458A now is in production for about 25 years , and only around 50k
> >> units have been sold.
> >> (That's an estimation by Joe Gellers series number collection)
> >>
> >> As the 3458A is a niche product with homeopathic series volume, the
> >> development, verification/validation, special reliability engineering,
> >> selection and burn-in measures, QA costs had to be paid per unit in the
> >> beginning.
> >>
> >> To my opinion, especially the 3458A was designed mainly for military
> >> requirements (Tamb 55°C). The military was willing to pay a premium (HP
> >> = High Price) at that time. So HP was able to realize that price.
> >>

Re: [volt-nuts] What made a HP3458A so expensive

[Tom Knox]

Actually in spite of it's high price I feel the 3458A represents a bargain. 
When it was introduced in 1989 it was $5900. A price it held for decades. 
Although designed in 
then 80's it's accuracy is still unsurpassed.  The 8846A is much less 
expensive because it has only about a quarter the parts. With few that 
are hand selected and/or aged. And all though both meter have well 
executed designs the result is the 3458A has about a magnitude greater 
accuracy. And anyone in Metrology can attest to the fact that the cost 
of accuracy is exponential. But the thought I wanted to contribute to the 
dialog is the real value of the 3458A is the body 
of knowledge built around the thousands of 358A's some running 
continuously for nearly three decades. The characteristics of the 3458A 
are perhaps the best documented of any electronic instrument ever made. 
That is priceless. When comparing that body of knowledge to individual 
units I have found every 3458A is a little different and seem to each 
have their own personality. In a side note, recently I owned what appeared to 
be the original 3458A. I cannot remember the serial number, but it had the 
numbered stickers identifying the boards that can be seen in the original 
service manual. And it was still  working flawlessly.

Thomas Knox



> Date: Sat, 18 Jan 2014 17:41:26 +0100
> From: frank.stellm...@freenet.de
> To: volt-nuts@febo.com
> Subject: [volt-nuts] What made a HP3458A so expensive
> 
> Well,
> 
> the 3458A now is in production for about 25 years , and only around 50k 
> units have been sold.
> (That's an estimation by Joe Gellers series number collection)
> 
> As the 3458A is a niche product with homeopathic series volume, the 
> development, verification/validation, special reliability engineering, 
> selection and burn-in measures, QA costs had to be paid per unit in the 
> beginning.
> 
> To my opinion, especially the 3458A was designed mainly for military 
> requirements (Tamb 55°C). The military was willing to pay a premium (HP 
> = High Price) at that time. So HP was able to realize that price.
> 
> All that development budget is long paid, and after end of the Cold War, 
> the military does not order so many devices anymore, what caused the 
> problems of the T&M business (finally => Keysight, urgh!).
> 
> But as that market is tight, competitors are few, so the price is not 
> going down, instead it's increasing over the years, from $5900 to around 
> $8500.
> 
> It would be interesting to calcualte the BOM of the 3458A.
> As they use many custom specific components, it should be relatively 
> expensive.
> 
> 
> 
> There is no parameter in the HP3458A specifications, that the device has 
> to be powered constantly to meet the specs.
> Those very high 8ppm/yr. drift might apply only during continuous 
> operation.
> During power down, the LTZ should not drift at all, as the ageing 
> mechanism is driven by temperature.
> But there might be (there are indeed) considerable hysteresis effects.
> 
> I have set the temperature of my HP3458A to ~ 60°C, I shut it down after 
> usage, and the periodical comparison to 3 other references shows a drift 
> of less than 1ppm/year.
> 
> Frank
> 
> 
> 
> 
> ___
> 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.