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

2014-07-08 Thread J. L. Trantham
Randy,

Yes, that is my understanding.  The person who would be able to definitively 
answer this question is Gary Bierman at Agilent at the Loveland Calibration 
Lab.  A very knowledgeable person regarding the 3458A.  I had a long talk with 
him before undertaking the purchase of my 3458A's.  I wound up with three 
3458A's for about the price of one new one.  All three 3458A's turned out to be 
functional with no failures.  All three were of similar 1990's to early 2000's 
vintage with the same major components.  Two were HP and one was Agilent, all 
made in the US.  I had no Malaysian units.

I removed the three Dallas chips in each of them, installed sockets, and 
installed new Dallas chips that I programmed with the data from their 
respective removed chips.  A total of 9 Dallas chips for the three units.

I also removed the single EPROM in each of them, installed a socket, and 
updated the firmware to the latest version I could find.

I managed to lose the CAL data from one of the units by, I think, trying to 
read it while still warm from the unsoldering process.  I calibrated that unit 
using some 'home standards' and a recently calibrated Solartron 7081 as the 
'transfer standard'.

I then sent the units in for Agilent Calibration, all three of which passed.  
Then I was able to avail myself of their 'service agreement' for each of the 
units.

They all agree very closely when measuring my now somewhat upgraded 'home 
standards'.

They are truly impressive units.

Good luck.

Joe

-Original Message-
From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf 
Of Randy Evans
Sent: Tuesday, July 08, 2014 9:29 AM
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Buying HP-3458A

Joe,

I imply from your e-mail that if I get a cheap 3458A that is complete but 
doesn't work, Agilent will repair it and calibrate it for a fixed fee of 
$2740.46, regardless of what is wrong with it?

Of course that means i would need to insure the unit is complete with no 
missing parts.

Randy


On Sun, Jul 6, 2014 at 3:15 PM, J. L. Trantham jlt...@att.net wrote:

 It is worth mentioning (re-mentioning) that once your 3458A passes 
 calibration with HP/Agilent/Keysight, etc., it becomes eligible for 
 their 'repair agreement' at $178.68 per year (with a small discount if 
 you purchase multiple years, up to a maximum of five years).  This 
 means that if it 'breaks' within that time period, it is repaired and 
 recalibrated for no additional charge.

 Per the Agilent US site, the 'repair per incident' charge is $2740.46.

 So, if you happen to get a 'good' 3458A that Agilent calibrates, you 
 can then get the service agreement (insurance policy?), which applies 
 even if you do not change the NVRAM's.  If they die, send it back to 
 Agilent and they will repair and recalibrate.

 In my shop, the 3458A is the 'house standard' that I use to measure 
 the resistance standards and voltage standards that I have.

 Joe

 -Original Message-
 From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] 
 On Behalf Of R.Phillips
 Sent: Sunday, July 06, 2014 2:08 PM
 To: Discussion of precise voltage measurement
 Subject: Re: [volt-nuts] Buying HP-3458A

 Randy
 I'm already forgetting some of the facts that made up the price that I 
 paid for the repair and re-cal. for my 3458A, as I have been involved 
 in a number of other restoration/repairs, but it was remarkably 
 similar in £ sterling, against your US $ price - so I guess it would 
 seem to be a fixed charge ? My instrument failed when the 'classic' 
 RAM/ROM 's ran out of battery support and further, they found another section 
 which had gone bad.
 There's nothing to give your more confidence than the Agilent 
 Calibration Certificate that comes with the package,as this is 
 probably the prime instrument in the collection of we lucky owners, so 
 it has to be good.  As I have stated in a previous exchange, the 'new' 
 processor/ROM/RAM board is now fitted with sockets, and the devices 
 that were formerly fitted, have been replaced with the new type that 
 only connect the battery support power when they are plugged in to their 
 sockets.
 Roy


 -Original Message-
 From: Randy Evans
 Sent: Sunday, July 06, 2014 6:44 PM
 To: Discussion of precise voltage measurement
 Subject: Re: [volt-nuts] Buying HP-3458A

 That e-mail I referenced is several years old.  i believe the current 
 repair price is just over $2800.

 Randy


 On Sat, Jul 5, 2014 at 10:49 PM, John Phillips 
 john.philli...@gmail.com
 wrote:

  ​They do really offer that service as​ long as you send them a 
  complete meter... No missing parts. Well they will take a few 
  missing screws and such. My experience with them is they charge the 
  same no mater what need to be fixed. Not sure what the price is, 
  there prices are country dependent.
  I
  thought it was a little more than $2200 last I checked.
 
 
  On Sat, Jul 5, 2014 at 4:08 PM

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

2014-07-06 Thread 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
 volt-nuts%40febo.com?Subject=Re%3A%20%5Bvolt-nuts%5D%203458A%20questionsIn-Reply-To=%3C001b01cc7960%24a15d2840%24e41778c0%24%40net%3E
 *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
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Re: [volt-nuts] Buying HP-3458A

2014-07-06 Thread Dr. David Kirkby (Kirkby Microwave Ltd)
On 6 Jul 2014 07:12, John Phillips john.philli...@gmail.com wrote:

 ​They do really offer that service as​ long as you send them a complete
 meter... No missing parts. Well they will take a few missing screws and
 such.

There is also the possibility someone has tried repairing it, but done so
badly.

I assume that there has been some design changes over the years, so not all
boards are identical.  Agilent would probably decline to fix a unit made
from parts from a mixture of revisions.

Buying one and hoping to get it repaired for a fixed fee seems a bit risky
to me.

Dave

My experience with them is they charge the same no mater what need to
 be fixed. Not sure what the price is, there prices are country dependent.
I
 thought it was a little more than $2200 last I checked.


 On Sat, Jul 5, 2014 at 4:08 PM, Randy Evans randyevans2...@gmail.com
 wrote:

  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
  volt-nuts%
 
40febo.com?Subject=Re%3A%20%5Bvolt-nuts%5D%203458A%20questionsIn-Reply-To=%3C001b01cc7960%24a15d2840%24e41778c0%24%40net%3E
  
  *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.
 



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

2014-07-06 Thread R.Phillips
I note with interest your considerations with restoring the 3458A.  I have 
recently had my 3458A restored (April-last) to fine working order, and 
calibrated by the Agilent Service Department here in the UK. It will cost 
what is required after their inspection - this inspection is a 'free' 
service which gives you a full appraisal, and a price for what has to be 
done to restore the instrument to 100% working order followed by 
re-calibration. If the cost is unacceptable, you can request the return your 
instrument back with a report on what would be required. The reality is that 
many owners have tried to make a 'cheaper fix' and finished up with an 
unsatisfactory result, as Agilent are not try to calibrate a faulty unit. 
Over the period of the models production, a number of changes have been 
introduced, I now have the latest type of processor/RAM/ROM board which is 
much improved. Considering the cost of a new instrument, I would suggest 
this is the best solution. I found the staff here in the UK to be very 
helpful and willing to discuss any technical matter.

Roy Phillips.

-Original Message- 
From: acb...@gmx.de

Sent: Sunday, July 06, 2014 9:45 AM
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Buying HP-3458A

I recently bought a non-working 3458, so faced the same problem. it was a 
relatively old unit, and I asked agilent germany (where I live) for a 
standard repair quote. they answered they would not give a fix price, they 
would evaluate the costs once received. it may have been linked to the age 
of the unit (SN arround 3k). I would therefore think that in other places in 
europe the response may be similar. it may be differnt in the US.
I determined the A/D board was faulty, and I did a check on that, it would 
have been considerably cheaper to just replace this. so for me, since I am 
also calibrating the unit myself, it would anyway have been a bad deal. 
fortunatelly I could fix the a/d myself, so could save this as well. given 
my buy price and list price for the a/d baord, it would otherwise probably 
have been a no so good deal. so I would say there is really some risk 
involved buying an old gear. also, keep in mind, boards may work but still 
be out of spec. so you may need a new A/D board just to figure out later 
that the ac board is not within specs either.
key I guess is that the error messages give you a reasonable understanding 
whats wrong. find out the cost of this board, and if thats ok in total it 
may make sense, but you still have quite a risk as the other items may have 
an issue as well. if a unit is completely dead, I would probably not buy. as 
far as i know you cannot buy a new PU board allone, you need to send it in 
to repair (thats what agilent germany states on ther parts list side), and 
then it may be very costly if other stuff it broken too.




Gesendet: Sonntag, 06. Juli 2014 um 07:03 Uhr
Von: Dr. David Kirkby (Kirkby Microwave Ltd) 
drkir...@kirkbymicrowave.co.uk

An: Discussion of precise voltage measurement volt-nuts@febo.com
Betreff: Re: [volt-nuts] Buying HP-3458A

On 6 Jul 2014 07:12, John Phillips john.philli...@gmail.com wrote:

 ​They do really offer that service as​ long as you send them a complete
 meter... No missing parts. Well they will take a few missing screws and
 such.

There is also the possibility someone has tried repairing it, but done so
badly.

I assume that there has been some design changes over the years, so not 
all

boards are identical.  Agilent would probably decline to fix a unit made
from parts from a mixture of revisions.

Buying one and hoping to get it repaired for a fixed fee seems a bit risky
to me.

Dave

My experience with them is they charge the same no mater what need to
 be fixed. Not sure what the price is, there prices are country 
 dependent.

I
 thought it was a little more than $2200 last I checked.


 On Sat, Jul 5, 2014 at 4:08 PM, Randy Evans randyevans2...@gmail.com
 wrote:

  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
  volt-nuts%
 
40febo.com?Subject=Re%3A%20%5Bvolt-nuts%5D%203458A%20questionsIn-Reply-To=%3C001b01cc7960%24a15d2840%24e41778c0%24%40net%3E
  
  *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

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

2014-07-06 Thread John Phillips
Can you buy the A/D board... here in USA they will not sell the parts
anymore. If you need a front panel because the display is dim or one of the
keys will not work it cost the same as any other repair.

acben, what was wrong with your A/D? The typical rundown error seems like
it would be real hard to repair and most of the circuit is contained in
proprietary chips. I am impressed. would love to be able to repair the A/D
board. That and the AC board are the highest failed boards I see.


On Sun, Jul 6, 2014 at 4:56 AM, R.Phillips phill...@btinternet.com wrote:

 I note with interest your considerations with restoring the 3458A.  I have
 recently had my 3458A restored (April-last) to fine working order, and
 calibrated by the Agilent Service Department here in the UK. It will cost
 what is required after their inspection - this inspection is a 'free'
 service which gives you a full appraisal, and a price for what has to be
 done to restore the instrument to 100% working order followed by
 re-calibration. If the cost is unacceptable, you can request the return
 your instrument back with a report on what would be required. The reality
 is that many owners have tried to make a 'cheaper fix' and finished up with
 an unsatisfactory result, as Agilent are not try to calibrate a faulty
 unit. Over the period of the models production, a number of changes have
 been introduced, I now have the latest type of processor/RAM/ROM board
 which is much improved. Considering the cost of a new instrument, I would
 suggest this is the best solution. I found the staff here in the UK to be
 very helpful and willing to discuss any technical matter.
 Roy Phillips.

 -Original Message- From: acb...@gmx.de
 Sent: Sunday, July 06, 2014 9:45 AM
 To: Discussion of precise voltage measurement
 Subject: Re: [volt-nuts] Buying HP-3458A


 I recently bought a non-working 3458, so faced the same problem. it was a
 relatively old unit, and I asked agilent germany (where I live) for a
 standard repair quote. they answered they would not give a fix price, they
 would evaluate the costs once received. it may have been linked to the age
 of the unit (SN arround 3k). I would therefore think that in other places
 in europe the response may be similar. it may be differnt in the US.
 I determined the A/D board was faulty, and I did a check on that, it would
 have been considerably cheaper to just replace this. so for me, since I am
 also calibrating the unit myself, it would anyway have been a bad deal.
 fortunatelly I could fix the a/d myself, so could save this as well. given
 my buy price and list price for the a/d baord, it would otherwise probably
 have been a no so good deal. so I would say there is really some risk
 involved buying an old gear. also, keep in mind, boards may work but still
 be out of spec. so you may need a new A/D board just to figure out later
 that the ac board is not within specs either.
 key I guess is that the error messages give you a reasonable understanding
 whats wrong. find out the cost of this board, and if thats ok in total it
 may make sense, but you still have quite a risk as the other items may have
 an issue as well. if a unit is completely dead, I would probably not buy.
 as far as i know you cannot buy a new PU board allone, you need to send it
 in to repair (thats what agilent germany states on ther parts list side),
 and then it may be very costly if other stuff it broken too.


  Gesendet: Sonntag, 06. Juli 2014 um 07:03 Uhr
 Von: Dr. David Kirkby (Kirkby Microwave Ltd) 
 drkir...@kirkbymicrowave.co.uk
 An: Discussion of precise voltage measurement volt-nuts@febo.com
 Betreff: Re: [volt-nuts] Buying HP-3458A

 On 6 Jul 2014 07:12, John Phillips john.philli...@gmail.com wrote:
 
  ​They do really offer that service as​ long as you send them a complete
  meter... No missing parts. Well they will take a few missing screws and
  such.

 There is also the possibility someone has tried repairing it, but done so
 badly.

 I assume that there has been some design changes over the years, so not
 all
 boards are identical.  Agilent would probably decline to fix a unit made
 from parts from a mixture of revisions.

 Buying one and hoping to get it repaired for a fixed fee seems a bit risky
 to me.

 Dave

 My experience with them is they charge the same no mater what need to
  be fixed. Not sure what the price is, there prices are country 
 dependent.
 I
  thought it was a little more than $2200 last I checked.
 
 
  On Sat, Jul 5, 2014 at 4:08 PM, Randy Evans randyevans2...@gmail.com
  wrote:
 
   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
   volt-nuts%
  
 40febo.com?Subject=Re%3A%20%5Bvolt-nuts%5D%203458A%
 20questionsIn-Reply-To=%3C001b01cc7960%24a15d2840%24e41778c0%24%40net%3E
   
   *Thu Sep 22 19:48:41 UTC 2011*
  
   If Agilent will fix everything, bring it up to specs

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

2014-07-06 Thread Randy Evans
That e-mail I referenced is several years old.  i believe the current
repair price is just over $2800.

Randy


On Sat, Jul 5, 2014 at 10:49 PM, John Phillips john.philli...@gmail.com
wrote:

 ​They do really offer that service as​ long as you send them a complete
 meter... No missing parts. Well they will take a few missing screws and
 such. My experience with them is they charge the same no mater what need to
 be fixed. Not sure what the price is, there prices are country dependent. I
 thought it was a little more than $2200 last I checked.


 On Sat, Jul 5, 2014 at 4:08 PM, Randy Evans randyevans2...@gmail.com
 wrote:

  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
  volt-nuts%
 
 40febo.com?Subject=Re%3A%20%5Bvolt-nuts%5D%203458A%20questionsIn-Reply-To=%3C001b01cc7960%24a15d2840%24e41778c0%24%40net%3E
  
  *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.
 



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

2014-07-06 Thread R.Phillips

Randy
I'm already forgetting some of the facts that made up the price that I paid 
for the repair and re-cal. for my 3458A, as I have been involved in a number 
of other restoration/repairs, but it was remarkably similar in £ sterling, 
against your US $ price - so I guess it would seem to be a fixed charge ? My 
instrument failed when the 'classic' RAM/ROM 's ran out of battery support 
and further, they found another section which had gone bad. There's nothing 
to give your more confidence than the Agilent Calibration Certificate that 
comes with the package,as this is probably the prime instrument in the 
collection of we lucky owners, so it has to be good.  As I have stated in a 
previous exchange, the 'new' processor/ROM/RAM board is now fitted with 
sockets, and the devices that were formerly fitted, have been replaced with 
the new type that only connect the battery support power when they are 
plugged in to their sockets.

Roy


-Original Message- 
From: Randy Evans

Sent: Sunday, July 06, 2014 6:44 PM
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Buying HP-3458A

That e-mail I referenced is several years old.  i believe the current
repair price is just over $2800.

Randy


On Sat, Jul 5, 2014 at 10:49 PM, John Phillips john.philli...@gmail.com
wrote:


​They do really offer that service as​ long as you send them a complete
meter... No missing parts. Well they will take a few missing screws and
such. My experience with them is they charge the same no mater what need 
to
be fixed. Not sure what the price is, there prices are country dependent. 
I

thought it was a little more than $2200 last I checked.


On Sat, Jul 5, 2014 at 4:08 PM, Randy Evans randyevans2...@gmail.com
wrote:

 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
 volt-nuts%

40febo.com?Subject=Re%3A%20%5Bvolt-nuts%5D%203458A%20questionsIn-Reply-To=%3C001b01cc7960%24a15d2840%24e41778c0%24%40net%3E
 
 *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.




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

2014-07-06 Thread Attila Kinali
Moin moin,

On Sun, 6 Jul 2014 10:45:51 +0200
acb...@gmx.de wrote:

  so for me, since I am also calibrating the unit myself,

I would be very much interested in how you calibrate the 3458 and
what you use as calibration standard.

Attila Kinali

-- 
I pity people who can't find laughter or at least some bit of amusement in
the little doings of the day. I believe I could find something ridiculous
even in the saddest moment, if necessary. It has nothing to do with being
superficial. It's a matter of joy in life.
-- Sophie Scholl
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Re: [volt-nuts] Buying HP-3458A

2014-07-06 Thread acbern
well, some time ago, when I bought my first 3458A, I looked into the data sheet 
of the 3458a and I figured that the basic accuracy of their standards is not 
terribly good. 2ppm each, you need to add this to all their specs. dont get me 
wrong, for most it is really sufficient, but as we are all a little nuts, I 
felt I would rather spend the money needed to calibrate the 3458a on a yearly 
basis for something else.
so I use a 732a and a 4910 as voltage references, and a very stable resistor. 
the 732a can be calibrated to appr. 1ppm at relatively little cost here, the 
10k resistor is in the 2ppm range, but simply because I did not want to spend 
the money for sub 1 ppm. calibrating both on a yearly basis is much cheaper 
than sending the 3458a for cal. I still need to establish the stability of the 
references, but the voltage references should be below 1ppm drift pa, the 10k 
below 0.5ppm (fluke also has a good appnote on establishing sub ppm stability 
with te 732A). so eventually I can move to a cal once every 2 years or so. and 
of course now, I can do the cal every 90 days to maintain 90 day accuracy. do 
that through an eternal lab, costs you a fortune.

now with these, you have only adjusted the meter, you still need to do 
performance verification. to do this, you need to have more precision gear, 
which i already had to some extent. the good thing is, some of it does not need 
cal., or is self-cailbrating.
all dcv is valiated with a 752a divider (self-calibrating) and a 
nanovolt-nullmeter. current validation is with a set of precision resistors, 
these are derived from the calibrated 10k with proper error propagation calc. 
it turns out that using the voltage divider method with the high linearity of 
the 3458a meter (in conjunction with a very stable voltage source) achieves 
precise enough resistor accuracies to do current verification. for ac you need 
a set of thermal converters or an ac transfer standard (ballantine 1605 e.g.) 
and a ratio transformer. question of course is, do you really need the ac 
function verified, most applications really focus on the dcv and ohms 
measurement. so here some money can be saved on gear.
again, this allows to keep the 3458a at a much higher acc. level than using an 
external cal lab, especially if you do it on a 90 day basis. or you could opt 
to just verify selected functions, even on a more regular basis. all depends on 
your needs.
performance verification is time consuming though, if you do it well. 



 Gesendet: Sonntag, 06. Juli 2014 um 19:18 Uhr
 Von: Attila Kinali att...@kinali.ch
 An: Discussion of precise voltage measurement volt-nuts@febo.com
 Betreff: Re: [volt-nuts] Buying HP-3458A

 Moin moin,
 
 On Sun, 6 Jul 2014 10:45:51 +0200
 acb...@gmx.de wrote:
 
   so for me, since I am also calibrating the unit myself,
 
 I would be very much interested in how you calibrate the 3458 and
 what you use as calibration standard.
 
   Attila Kinali
 
 -- 
 I pity people who can't find laughter or at least some bit of amusement in
 the little doings of the day. I believe I could find something ridiculous
 even in the saddest moment, if necessary. It has nothing to do with being
 superficial. It's a matter of joy in life.
   -- Sophie Scholl
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Re: [volt-nuts] Buying HP-3458A

2014-07-06 Thread J. L. Trantham
It is worth mentioning (re-mentioning) that once your 3458A passes calibration 
with HP/Agilent/Keysight, etc., it becomes eligible for their 'repair 
agreement' at $178.68 per year (with a small discount if you purchase multiple 
years, up to a maximum of five years).  This means that if it 'breaks' within 
that time period, it is repaired and recalibrated for no additional charge.

Per the Agilent US site, the 'repair per incident' charge is $2740.46.  

So, if you happen to get a 'good' 3458A that Agilent calibrates, you can then 
get the service agreement (insurance policy?), which applies even if you do not 
change the NVRAM's.  If they die, send it back to Agilent and they will repair 
and recalibrate.

In my shop, the 3458A is the 'house standard' that I use to measure the 
resistance standards and voltage standards that I have.

Joe

-Original Message-
From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf 
Of R.Phillips
Sent: Sunday, July 06, 2014 2:08 PM
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Buying HP-3458A

Randy
I'm already forgetting some of the facts that made up the price that I paid for 
the repair and re-cal. for my 3458A, as I have been involved in a number of 
other restoration/repairs, but it was remarkably similar in £ sterling, against 
your US $ price - so I guess it would seem to be a fixed charge ? My instrument 
failed when the 'classic' RAM/ROM 's ran out of battery support and further, 
they found another section which had gone bad. There's nothing to give your 
more confidence than the Agilent Calibration Certificate that comes with the 
package,as this is probably the prime instrument in the collection of we lucky 
owners, so it has to be good.  As I have stated in a previous exchange, the 
'new' processor/ROM/RAM board is now fitted with sockets, and the devices that 
were formerly fitted, have been replaced with the new type that only connect 
the battery support power when they are plugged in to their sockets.
Roy


-Original Message-
From: Randy Evans
Sent: Sunday, July 06, 2014 6:44 PM
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Buying HP-3458A

That e-mail I referenced is several years old.  i believe the current repair 
price is just over $2800.

Randy


On Sat, Jul 5, 2014 at 10:49 PM, John Phillips john.philli...@gmail.com
wrote:

 ​They do really offer that service as​ long as you send them a 
 complete meter... No missing parts. Well they will take a few missing 
 screws and such. My experience with them is they charge the same no 
 mater what need to be fixed. Not sure what the price is, there prices 
 are country dependent.
 I
 thought it was a little more than $2200 last I checked.


 On Sat, Jul 5, 2014 at 4:08 PM, Randy Evans randyevans2...@gmail.com
 wrote:

  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 volt-nuts%
 
 40febo.com?Subject=Re%3A%20%5Bvolt-nuts%5D%203458A%20questionsIn-Repl
 y-To=%3C001b01cc7960%24a15d2840%24e41778c0%24%40net%3E
  
  *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
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 --
 John Phillips
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