Buying HP-3458A
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" attila@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
acbern@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
--
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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
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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-bounces@febo.com [mailto:volt-nuts-bounces@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.phillips0@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 randyevans2688@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%20questions&In-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
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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and follow the instructions there.
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and follow the instructions there.
As a side note,
I recently filled out a survey request from Agilent as a response to my
recent 3458A calibration. Basically, they asked about any improvements that
would be welcome on the 3458A.
After giving them a small list of recommendations and requesting that
anything that could be implemented in firmware be offered as an update
either as new EPROMs or as a new outguard logic board.
I also mentioned that the features should be added to the replacement model
("3458B"?).
I had no hope that anything would be added, but I thought it would be
interesting to see if anyone actually took the time to respond.
The official response was that the 3458A is probably not getting any
improvements, and that there are no plans for a "3458B". At this time, they
plan on manufacturing the 3458A through 2017.
Todd
On Sun, Jul 6, 2014 at 6:15 PM, J. L. Trantham jltran@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-bounces@febo.com [mailto:volt-nuts-bounces@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.phillips0@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 randyevans2688@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%20questions&In-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
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
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and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to
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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.
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 jltran@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-bounces@febo.com [mailto:volt-nuts-bounces@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.phillips0@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 randyevans2688@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%20questions&In-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
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
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and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to
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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.
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-bounces@febo.com [mailto:volt-nuts-bounces@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 jltran@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-bounces@febo.com [mailto:volt-nuts-bounces@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.phillips0@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
randyevans2688@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%20questions&In-Re
pl 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
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
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and follow the instructions there.
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and follow the instructions there.
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and follow the instructions there.
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and follow the instructions there.
I agree with Joe that he is very intimately familiar with the 3458A. He said he is the young guy with the least amount of time working on these meters (approx 30+yrs).
Gary told me that all repairs are done to the component level. He also said that the meters are tested to the same specs as a brand new unit. The repair process involves testing all the relays, rc networks in the ac section, etc... If I remember correctly, the calibrations are done to 24hr specs too.
What you will end up with is a meter that functions as new. When it is complete, you can purchase up to a 5 yr service plan.
I am not sure about any cosmetic issues though. Agilent probably won't replace covers because they look worn. It is probably best to ask first before sending in your meter. I like my gear to look as new as possible and I would hate to have an old beat up panel for 5yrs for fear of voiding the service agreement.
Also, I was able to give Gary other serial numbers and he was able to tell me if the meter was ever serviced by Agilent.
Todd
Sent from my iPad
On Jul 8, 2014, at 13:23, "J. L. Trantham" jltran@att.net wrote:
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-bounces@febo.com [mailto:volt-nuts-bounces@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 jltran@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-bounces@febo.com [mailto:volt-nuts-bounces@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.phillips0@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
randyevans2688@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%20questions&In-Re
pl 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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