Empathy List Archives

DM

Dave M

Sat, Jul 8, 2017 2:05 PM

David,
I have a 332B as well, although it's been loaned out for the past couple of
years to a friend. I have the US Army manual PDF also, and have found it to
be pretty complete, at least complete enough to get us through a couple of
repairs.
What is missing from the manual?

The second page in the PDF has a statement that says:
"This manual is an authentication of the manufacturer’s commercial
literature which, through usage, has been found to cover the data required
to operate and maintain this equipment. Since the manual was not prepared in
accordance with military specifications, the format has not been structured
to consider level of maintenance, nor to include a formal section on depot
overhaul standards.
This manual contains copyrighted information that is printed with permission
of John Fluke Manufacturing Company, Seattle, Washington."

From that statement, I expect that the Army manual is just a reproduction of

the commercial Fluke manual for the 332B.

Cheers,
Dave M

David C. Partridge wrote:

Amongst the stuff I recently acquired is a Fluke 332B (sn 4151).

I found the manual for the 332D on the Fluke website, but can't find
one specifically for the 332B apart from an incomplete US Army
version.

I have some questions:

Does anyone know where I can find the matching manual
If not, how useful is the 332D manual?
It was last calibrated in 2010, and appears to be consistently low
in output (about 5mV at 100V, 25mV at 500V, 50mV at 1000V) after
being on for an hour. Is that the sort of error I should expect
after that period?
I'm leery of the chopper amp, did anyone (Dr. Frank?) do a
retrofit using a modern chopper op-amp or similar?

Thanks
Dave

David, I have a 332B as well, although it's been loaned out for the past couple of years to a friend. I have the US Army manual PDF also, and have found it to be pretty complete, at least complete enough to get us through a couple of repairs. What is missing from the manual? The second page in the PDF has a statement that says: "This manual is an authentication of the manufacturer’s commercial literature which, through usage, has been found to cover the data required to operate and maintain this equipment. Since the manual was not prepared in accordance with military specifications, the format has not been structured to consider level of maintenance, nor to include a formal section on depot overhaul standards. This manual contains copyrighted information that is printed with permission of John Fluke Manufacturing Company, Seattle, Washington." >From that statement, I expect that the Army manual is just a reproduction of the commercial Fluke manual for the 332B. Cheers, Dave M David C. Partridge wrote: > Amongst the stuff I recently acquired is a Fluke 332B (sn 4151). > > I found the manual for the 332D on the Fluke website, but can't find > one specifically for the 332B apart from an incomplete US Army > version. > > I have some questions: > > 1) Does anyone know where I can find the matching manual > > 2) If not, how useful is the 332D manual? > > 3) It was last calibrated in 2010, and appears to be consistently low > in output (about 5mV at 100V, 25mV at 500V, 50mV at 1000V) after > being on for an hour. Is that the sort of error I should expect > after that period? > > 4) I'm leery of the chopper amp, did anyone (Dr. Frank?) do a > retrofit using a modern chopper op-amp or similar? > > > Thanks > Dave

JP

Jason Pepas

Sat, Jul 8, 2017 8:06 PM

Following this thread eagerly -- I just won a 332B on ebay last week!

On Sat, Jul 8, 2017 at 9:05 AM, Dave M dgminala@mediacombb.net wrote:

David,
I have a 332B as well, although it's been loaned out for the past couple
of years to a friend. I have the US Army manual PDF also, and have found
it to be pretty complete, at least complete enough to get us through a
couple of repairs.
What is missing from the manual?

The second page in the PDF has a statement that says:
"This manual is an authentication of the manufacturer’s commercial
literature which, through usage, has been found to cover the data required
to operate and maintain this equipment. Since the manual was not prepared
in accordance with military specifications, the format has not been
structured to consider level of maintenance, nor to include a formal
section on depot overhaul standards.
This manual contains copyrighted information that is printed with
permission of John Fluke Manufacturing Company, Seattle, Washington."

From that statement, I expect that the Army manual is just a reproduction
of the commercial Fluke manual for the 332B.

Cheers,
Dave M

David C. Partridge wrote:

Amongst the stuff I recently acquired is a Fluke 332B (sn 4151).

I found the manual for the 332D on the Fluke website, but can't find
one specifically for the 332B apart from an incomplete US Army
version.

I have some questions:

Does anyone know where I can find the matching manual
If not, how useful is the 332D manual?
It was last calibrated in 2010, and appears to be consistently low
in output (about 5mV at 100V, 25mV at 500V, 50mV at 1000V) after
being on for an hour. Is that the sort of error I should expect
after that period?
I'm leery of the chopper amp, did anyone (Dr. Frank?) do a
retrofit using a modern chopper op-amp or similar?

Thanks
Dave

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To unsubscribe, go to https://www.febo.com/cgi-bin/m
ailman/listinfo/volt-nuts
and follow the instructions there.

Following this thread eagerly -- I just won a 332B on ebay last week! On Sat, Jul 8, 2017 at 9:05 AM, Dave M <dgminala@mediacombb.net> wrote: > David, > I have a 332B as well, although it's been loaned out for the past couple > of years to a friend. I have the US Army manual PDF also, and have found > it to be pretty complete, at least complete enough to get us through a > couple of repairs. > What is missing from the manual? > > The second page in the PDF has a statement that says: > "This manual is an authentication of the manufacturer’s commercial > literature which, through usage, has been found to cover the data required > to operate and maintain this equipment. Since the manual was not prepared > in accordance with military specifications, the format has not been > structured to consider level of maintenance, nor to include a formal > section on depot overhaul standards. > This manual contains copyrighted information that is printed with > permission of John Fluke Manufacturing Company, Seattle, Washington." > > From that statement, I expect that the Army manual is just a reproduction > of the commercial Fluke manual for the 332B. > > Cheers, > Dave M > > > David C. Partridge wrote: > >> Amongst the stuff I recently acquired is a Fluke 332B (sn 4151). >> >> I found the manual for the 332D on the Fluke website, but can't find >> one specifically for the 332B apart from an incomplete US Army >> version. >> >> I have some questions: >> >> 1) Does anyone know where I can find the matching manual >> >> 2) If not, how useful is the 332D manual? >> >> 3) It was last calibrated in 2010, and appears to be consistently low >> in output (about 5mV at 100V, 25mV at 500V, 50mV at 1000V) after >> being on for an hour. Is that the sort of error I should expect >> after that period? >> >> 4) I'm leery of the chopper amp, did anyone (Dr. Frank?) do a >> retrofit using a modern chopper op-amp or similar? >> >> >> Thanks >> Dave >> > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/m > ailman/listinfo/volt-nuts > and follow the instructions there. >

DC

David C. Partridge

Sun, Jul 9, 2017 10:38 AM

I have the offer of a bare PCB for a replacement chopper circuit which is described here:

http://www.friedrich-messtechnik.de/index.php/bauanleitungen/87-fluke335-332

When running through the calibration of the unit last night, I found that it was really quite noisy with the output varying by 10s of micro-volts, and the calibration potentiometers were also quite noisy and difficult to set accurately (I was using NPLC 100 setting).

So, is it worthwhile to replace the chopper amplifier board and replace electrolytic caps or would that just make marginal improvements (I saw one of Dr. Frank's posts on EEVBLOG indicating that these were quite noisy beasts).

If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ...

Now to try to lug the 4808 up to my work room to see it that will work!

Dave
-----Original Message-----
From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of Jason Pepas
Sent: 08 July 2017 21:07
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Fluke 332B

Following this thread eagerly -- I just won a 332B on ebay last week!

On Sat, Jul 8, 2017 at 9:05 AM, Dave M dgminala@mediacombb.net wrote:

David,
I have a 332B as well, although it's been loaned out for the past
couple of years to a friend. I have the US Army manual PDF also, and
have found it to be pretty complete, at least complete enough to get
us through a couple of repairs.
What is missing from the manual?

The second page in the PDF has a statement that says:
"This manual is an authentication of the manufacturer’s commercial
literature which, through usage, has been found to cover the data
required to operate and maintain this equipment. Since the manual was
not prepared in accordance with military specifications, the format
has not been structured to consider level of maintenance, nor to
include a formal section on depot overhaul standards.
This manual contains copyrighted information that is printed with
permission of John Fluke Manufacturing Company, Seattle, Washington."

From that statement, I expect that the Army manual is just a
reproduction of the commercial Fluke manual for the 332B.

Cheers,
Dave M

David C. Partridge wrote:

Amongst the stuff I recently acquired is a Fluke 332B (sn 4151).

I found the manual for the 332D on the Fluke website, but can't find
one specifically for the 332B apart from an incomplete US Army
version.

I have some questions:

Does anyone know where I can find the matching manual
If not, how useful is the 332D manual?
It was last calibrated in 2010, and appears to be consistently low
in output (about 5mV at 100V, 25mV at 500V, 50mV at 1000V) after
being on for an hour. Is that the sort of error I should expect
after that period?
I'm leery of the chopper amp, did anyone (Dr. Frank?) do a
retrofit using a modern chopper op-amp or similar?

Thanks
Dave

volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/m ailman/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.

I have the offer of a bare PCB for a replacement chopper circuit which is described here: <http://www.friedrich-messtechnik.de/index.php/bauanleitungen/87-fluke335-332> When running through the calibration of the unit last night, I found that it was really quite noisy with the output varying by 10s of micro-volts, and the calibration potentiometers were also quite noisy and difficult to set accurately (I was using NPLC 100 setting). So, is it worthwhile to replace the chopper amplifier board and replace electrolytic caps or would that just make marginal improvements (I saw one of Dr. Frank's posts on EEVBLOG indicating that these were quite noisy beasts). If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ... Now to try to lug the 4808 up to my work room to see it that will work! Dave -----Original Message----- From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of Jason Pepas Sent: 08 July 2017 21:07 To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 332B Following this thread eagerly -- I just won a 332B on ebay last week! On Sat, Jul 8, 2017 at 9:05 AM, Dave M <dgminala@mediacombb.net> wrote: > David, > I have a 332B as well, although it's been loaned out for the past > couple of years to a friend. I have the US Army manual PDF also, and > have found it to be pretty complete, at least complete enough to get > us through a couple of repairs. > What is missing from the manual? > > The second page in the PDF has a statement that says: > "This manual is an authentication of the manufacturer’s commercial > literature which, through usage, has been found to cover the data > required to operate and maintain this equipment. Since the manual was > not prepared in accordance with military specifications, the format > has not been structured to consider level of maintenance, nor to > include a formal section on depot overhaul standards. > This manual contains copyrighted information that is printed with > permission of John Fluke Manufacturing Company, Seattle, Washington." > > From that statement, I expect that the Army manual is just a > reproduction of the commercial Fluke manual for the 332B. > > Cheers, > Dave M > > > David C. Partridge wrote: > >> Amongst the stuff I recently acquired is a Fluke 332B (sn 4151). >> >> I found the manual for the 332D on the Fluke website, but can't find >> one specifically for the 332B apart from an incomplete US Army >> version. >> >> I have some questions: >> >> 1) Does anyone know where I can find the matching manual >> >> 2) If not, how useful is the 332D manual? >> >> 3) It was last calibrated in 2010, and appears to be consistently low >> in output (about 5mV at 100V, 25mV at 500V, 50mV at 1000V) after >> being on for an hour. Is that the sort of error I should expect >> after that period? >> >> 4) I'm leery of the chopper amp, did anyone (Dr. Frank?) do a >> retrofit using a modern chopper op-amp or similar? >> >> >> Thanks >> Dave >> > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to > https://www.febo.com/cgi-bin/m ailman/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.

CS

Charles Steinmetz

Sun, Jul 9, 2017 12:31 PM

David wrote:

When running through the calibration of the unit last night, I found that it was really quite noisy

So, is it worthwhile to replace the chopper amplifier board and replace electrolytic caps or would that just make marginal improvements

If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ...

My experience with these extends back to when they were new. They are
definitely noisy even when they are in perfect condition, and this many
years on they tend to be quite unreliable even if they have been
thoroughly gone through. Also, something I haven't seen mentioned much
is that the last decade (LSD) is purely for decoration. The accuracy of
the 332 on its best day is worse than one division of the second-last
decade.

In my expeience, the original choppers work very well unless they are
broken. I do not expect that a chopper-stabilized op amp would provide
meaningful improvement.

I advise passing on the 332A/B/D and holding out for a 5440B. You will
not be sorry.

Best regards,

Charles

David wrote: > When running through the calibration of the unit last night, I found that it was really quite noisy > > So, is it worthwhile to replace the chopper amplifier board and replace electrolytic caps or would that just make marginal improvements > > If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ... My experience with these extends back to when they were new. They are definitely noisy even when they are in perfect condition, and this many years on they tend to be quite unreliable even if they have been thoroughly gone through. Also, something I haven't seen mentioned much is that the last decade (LSD) is purely for decoration. The accuracy of the 332 on its best day is worse than one division of the second-last decade. In my expeience, the original choppers work very well unless they are broken. I do not expect that a chopper-stabilized op amp would provide meaningful improvement. I advise passing on the 332A/B/D and holding out for a 5440B. You will not be sorry. Best regards, Charles

DC

David C. Partridge

Sun, Jul 9, 2017 3:33 PM

Thanks Charles,

Dave

-----Original Message-----
From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of Charles Steinmetz
Sent: 09 July 2017 13:31
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Fluke 332B

David wrote:

When running through the calibration of the unit last night, I found
that it was really quite noisy

So, is it worthwhile to replace the chopper amplifier board and
replace electrolytic caps or would that just make marginal
improvements

If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ...

My experience with these extends back to when they were new. They are definitely noisy even when they are in perfect condition, and this many years on they tend to be quite unreliable even if they have been thoroughly gone through. Also, something I haven't seen mentioned much is that the last decade (LSD) is purely for decoration. The accuracy of the 332 on its best day is worse than one division of the second-last decade.

In my expeience, the original choppers work very well unless they are broken. I do not expect that a chopper-stabilized op amp would provide meaningful improvement.

I advise passing on the 332A/B/D and holding out for a 5440B. You will not be sorry.

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.

Thanks Charles, Dave -----Original Message----- From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of Charles Steinmetz Sent: 09 July 2017 13:31 To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 332B David wrote: > When running through the calibration of the unit last night, I found > that it was really quite noisy > > So, is it worthwhile to replace the chopper amplifier board and > replace electrolytic caps or would that just make marginal > improvements > > If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ... My experience with these extends back to when they were new. They are definitely noisy even when they are in perfect condition, and this many years on they tend to be quite unreliable even if they have been thoroughly gone through. Also, something I haven't seen mentioned much is that the last decade (LSD) is purely for decoration. The accuracy of the 332 on its best day is worse than one division of the second-last decade. In my expeience, the original choppers work very well unless they are broken. I do not expect that a chopper-stabilized op amp would provide meaningful improvement. I advise passing on the 332A/B/D and holding out for a 5440B. You will not be sorry. 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.

RK

Rob Klein

Sun, Jul 9, 2017 4:03 PM

Dave,

I don't know where you are based, but I happen to have two 5440B's I want to get rid of.

Anyone else in Europe who is interested can also react, of course :)

⁣Met vriendelijke groet,
Rob Klein

verstuurd vanaf mijn smartphone

Op 9 jul. 2017 17:33, om 17:33, "David C. Partridge" david.partridge@perdrix.co.uk schreef:

Thanks Charles,

Dave

-----Original Message-----
From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of
Charles Steinmetz
Sent: 09 July 2017 13:31
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Fluke 332B

David wrote:

When running through the calibration of the unit last night, I found
that it was really quite noisy

So, is it worthwhile to replace the chopper amplifier board and
replace electrolytic caps or would that just make marginal
improvements

If it would still be an unstable, noisy brute after I finished that,

then I think I'll put it on eBay ...

My experience with these extends back to when they were new. They are
definitely noisy even when they are in perfect condition, and this many
years on they tend to be quite unreliable even if they have been
thoroughly gone through. Also, something I haven't seen mentioned much
is that the last decade (LSD) is purely for decoration. The accuracy
of the 332 on its best day is worse than one division of the
second-last decade.

In my expeience, the original choppers work very well unless they are
broken. I do not expect that a chopper-stabilized op amp would provide
meaningful improvement.

I advise passing on the 332A/B/D and holding out for a 5440B. You will
not be sorry.

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.

Dave, I don't know where you are based, but I happen to have two 5440B's I want to get rid of. Anyone else in Europe who is interested can also react, of course :) ⁣Met vriendelijke groet, Rob Klein verstuurd vanaf mijn smartphone Op 9 jul. 2017 17:33, om 17:33, "David C. Partridge" <david.partridge@perdrix.co.uk> schreef: >Thanks Charles, > >Dave > >-----Original Message----- >From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of >Charles Steinmetz >Sent: 09 July 2017 13:31 >To: Discussion of precise voltage measurement >Subject: Re: [volt-nuts] Fluke 332B > >David wrote: > >> When running through the calibration of the unit last night, I found >> that it was really quite noisy > > >> So, is it worthwhile to replace the chopper amplifier board and >> replace electrolytic caps or would that just make marginal >> improvements >> >> If it would still be an unstable, noisy brute after I finished that, >then I think I'll put it on eBay ... > >My experience with these extends back to when they were new. They are >definitely noisy even when they are in perfect condition, and this many >years on they tend to be quite unreliable even if they have been >thoroughly gone through. Also, something I haven't seen mentioned much >is that the last decade (LSD) is purely for decoration. The accuracy >of the 332 on its best day is worse than one division of the >second-last decade. > >In my expeience, the original choppers work very well unless they are >broken. I do not expect that a chopper-stabilized op amp would provide >meaningful improvement. > >I advise passing on the 332A/B/D and holding out for a 5440B. You will >not be sorry. > >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.

R

roman

Mon, Jul 10, 2017 1:00 AM

Hi guys,
I am also watching this thread with interest.
I became infected with volt-nuttery many decades ago, fresh out of uni, in the standards lab for (then) Australia's big Telco. One of our workhorses was a newish 335 which I loved using - unlike Charles' experience, we all found the last digit to be "useful" and certainly useable in doing various transfers and comparison (not absolute accuracy, of course). Many years later I scored a 332B/AF ( Mosfet chopper, top three digits adjustable, and ref amp replaced (apparently) with LTFLU-1CH) but of uncertain provenance, and it has been one of my pet projects over the years. Again, I find the last digit fairly quiet when looking at the delta between it and a bank of Weston cells with a microvoltmeter.
Well. Quiet in the short term, but the unit does have issues at a 1-5 minutes time scale with random twitches and jumps, This is all part of my "project" to sort out.
So far I have made a number of modification to reduce the power consumption ( now around 11W idle down from around 32, with a consequent reduction in temp rise and warm-up time) and am now turning my attention to the precision bits.
I realise that some my just need a good calibrator without futzing around - and I am sure that the advice to "go 5440" is the right advice for many. Sadly, in Australia, there don't seem to be a bunch of people with 2 5440's they want to be rid of!
But I'm having lots of fun with my 332.

Roman

-----Original Message-----
From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of David C. Partridge
Sent: Monday, 10 July 2017 1:03 AM
To: 'Discussion of precise voltage measurement'
Subject: Re: [volt-nuts] Fluke 332B

Thanks Charles,

Dave

-----Original Message-----
From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of Charles Steinmetz
Sent: 09 July 2017 13:31
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Fluke 332B

David wrote:

When running through the calibration of the unit last night, I found
that it was really quite noisy

So, is it worthwhile to replace the chopper amplifier board and
replace electrolytic caps or would that just make marginal
improvements

If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ...

My experience with these extends back to when they were new. They are definitely noisy even when they are in perfect condition, and this many years on they tend to be quite unreliable even if they have been thoroughly gone through. Also, something I haven't seen mentioned much is that the last decade (LSD) is purely for decoration. The accuracy of the 332 on its best day is worse than one division of the second-last decade.

In my expeience, the original choppers work very well unless they are broken. I do not expect that a chopper-stabilized op amp would provide meaningful improvement.

I advise passing on the 332A/B/D and holding out for a 5440B. You will not be sorry.

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.

Hi guys, I am also watching this thread with interest. I became infected with volt-nuttery many decades ago, fresh out of uni, in the standards lab for (then) Australia's big Telco. One of our workhorses was a newish 335 which I loved using - unlike Charles' experience, we all found the last digit to be "useful" and certainly useable in doing various transfers and comparison (not absolute accuracy, of course). Many years later I scored a 332B/AF ( Mosfet chopper, top three digits adjustable, and ref amp replaced (apparently) with LTFLU-1CH) but of uncertain provenance, and it has been one of my pet projects over the years. Again, I find the last digit fairly quiet when looking at the delta between it and a bank of Weston cells with a microvoltmeter. Well. Quiet in the short term, but the unit does have issues at a 1-5 minutes time scale with random twitches and jumps, This is all part of my "project" to sort out. So far I have made a number of modification to reduce the power consumption ( now around 11W idle down from around 32, with a consequent reduction in temp rise and warm-up time) and am now turning my attention to the precision bits. I realise that some my just need a good calibrator without futzing around - and I am sure that the advice to "go 5440" is the right advice for many. Sadly, in Australia, there don't seem to be a bunch of people with 2 5440's they want to be rid of! But I'm having lots of fun with my 332. Roman -----Original Message----- From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of David C. Partridge Sent: Monday, 10 July 2017 1:03 AM To: 'Discussion of precise voltage measurement' Subject: Re: [volt-nuts] Fluke 332B Thanks Charles, Dave -----Original Message----- From: volt-nuts [mailto:volt-nuts-bounces@febo.com] On Behalf Of Charles Steinmetz Sent: 09 July 2017 13:31 To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 332B David wrote: > When running through the calibration of the unit last night, I found > that it was really quite noisy > > So, is it worthwhile to replace the chopper amplifier board and > replace electrolytic caps or would that just make marginal > improvements > > If it would still be an unstable, noisy brute after I finished that, then I think I'll put it on eBay ... My experience with these extends back to when they were new. They are definitely noisy even when they are in perfect condition, and this many years on they tend to be quite unreliable even if they have been thoroughly gone through. Also, something I haven't seen mentioned much is that the last decade (LSD) is purely for decoration. The accuracy of the 332 on its best day is worse than one division of the second-last decade. In my expeience, the original choppers work very well unless they are broken. I do not expect that a chopper-stabilized op amp would provide meaningful improvement. I advise passing on the 332A/B/D and holding out for a 5440B. You will not be sorry. 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.

volt-nuts@lists.febo.com

Re: [volt-nuts] Fluke 332B