开云体育

Steve, Jeff, and all,

My 2703Axxxxx 3457A also has the SAFT LX 1634, Lithium 3.0V, battery and

measures 3.032 VDC. Likewise, I can not see a date code on the battery,
even after removing the A1 Board and looking as far under the battery as
possible.

My A1 Board is 03457-665xx, REV A, 2703. According to the manual, this is
the 'New Main Controller'. However, on my board, A11R644 is a 17.4 K
resistor and A11R645 is a 13 K resistor which represents the 'old'

and matches the schematic. The 'new' resistors would be 13 K and 12.7 K
respectively, according to the parts list and 'Changes'. The 'old' battery
is listed as a 'Battery 2.9V .9A-HR Li/S-Diox W-Flex', according to the
Agilent website. Likewise, the Agilent website lists the 'new' battery as

'Battery 3V 1.2A-HR Lithium Poly Carbon'. Only the manual parts list lists
the 'new' battery as 3.4 V.

In addition, I don't think I have ever seen a 3.4 V Lithium battery.

So, the question is, when it comes time to replace the battery, what

be used?

Joe

-----Original Message-----
From: hp_agilent_equipment@...

[mailto:hp_agilent_equipment@...

Sent: Monday, December 31, 2012 11:20 AM
To: hp_agilent_equipment@...

Subject: Re: [hp_agilent_equipment] 3457a on the way

Joe and all,

I just had a quick look inside my 3457A again. Mine has the 3.0 volt
lithium battery, SAFT LX-1634. Obsolete at Agilent, as is the newer
battery. Google was no help either. Mine measures 3.03 volts and there's
no evidence of corrosion so that's good. I couldn't see a date code on
it; probably on the underneath side. I've replaced batteries by
paralleling the existing connections with an appropriate power supply
and then unsoldering the old battery with an isolated-tip iron and
soldering in the new battery. I've also carefully soldered a new battery
in parallel with the old and then clipped out the old one. No problems
with lost data so far.

I'm not sure how the cal numbers increment. I'll have to experiment with
that sometime. Right now I need to repair the 1349D display in my 8757A
so I can get on with a sweeper plug in project, so the volt-nuttery is
on hold for awhile.

Happy New Year to all!

Steve

On 12/30/2012 5:34 PM, J. L. Trantham wrote:

Steve,

Thanks for the data. Mine is also 2703A prefix with REV?:6,0 and
CALNUM?:98. Not a multiple of 34. Would be interesting to see what the
CALNUM increments by after an Agilent CAL.

I, too, need to look at the battery condition. I have not looked at the
manual regarding replacing the battery. Has anyone done that without
losing
the CAL Constants?

Joe

-----Original Message-----
From: hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
[mailto:hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>] On Behalf Of Steve
Sent: Sunday, December 30, 2012 4:14 PM
To: hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
Subject: Re: [hp_agilent_equipment] 3457a on the way

It would be interesting to see if a newer rev is out there. My 3457A
is s.n.
prefix 2703, with rev 6,0 and option 0, CALNUM=34. I wonder if that's a
default number for anything less than a full cal at Agilent? The last
calibration was at least 6 years ago and performed by what was then

Military Airplane Company's metrology lab. I need to open it up and

the battery condition.

Steve

On Dec 29, 2012, at 8:08 PM, "J. L. Trantham" <jltran@...

<mailto:jltran%40att.net>

<mailto:jltran%40att.net>
<mailto:jltran%40att.net> > wrote:

If the 'SELF TEST OK' message appears, there is no need to make any
'adjustments'. Just do the 'front panel CAL' if needed.

As I said, I would check it out, assume it is the best instrument in

your

collection, send it to Agilent for CAL and see what you get.

I would appreciate knowing what 'REV?' and 'OPT?' says when you get a
chance. 'CALNUM?' would be interesting as well.

In the 3458A, the firmware is in an EPROM (6 EPROM's for the older

units)

and can be removed, a socket placed, and easily upgraded by

purchasing the

latest pre-programmed EPROM (or EPROM's for the older units) from

Agilent.

The only problem is they have a $50 minimum for this $18 part for the

later

units.

My wife thinks I am going to appear on an episode of 'Hoarders'.

Joe

-----Original Message-----
From: hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
<mailto:hp_agilent_equipment%40yahoogroups.com>

[mailto:hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
<mailto:hp_agilent_equipment%40yahoogroups.com> ] On Behalf Of Jeff
Machesky

Sent: Saturday, December 29, 2012 8:01 PM
To: hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
<mailto:hp_agilent_equipment%40yahoogroups.com>

Subject: Re: [hp_agilent_equipment] 3457a on the way

Wow, lots of replies all of a sudden. I'm already prepping the wife

the $200 + price tag of calibration. Funny how when I was single I

would

have about $800 in cash in my wallet at all times and now I beg for 20
bucks, Hmm. Sad part is I make about 4 times the money. In any event
I've not received to much feedback on the "Self Test OK" message the
seller had posted. Any comments? I'm too much of a skeptic when it

comes

to eBay purchases. It's just a convenient place to purchase such

Any feedback would be appreciated as to possible pitfalls regarding

this

device. I like to prep for issues rather then build myself up for
failure. What do they say...it's better to be pleasantly surprised

let down.

Thanks,

Jeff

On 12/29/2012 5:40 PM, J. L. Trantham wrote:

According to the manual, there are only two 'adjustments' that can

made

on a 3457A, Input Offset Amplifier adjustment and AC Converter

Frequency

Response, both needed only if there is a 'HARDWARE ERR' failure

message

after 'TEST' is selected and then only if it is a specific

'AUXERR' or

16 or
256 is seen. Otherwise, all the calibrations are done from the front

panel

with specific inputs from the front panel.

The CALNUM? is incremented by 'several digits' with a 'complete
calibration', one for each calibration point entered, per the

Interestingly, when I sent my two 3458A's to Agilent for

the

CALNUM incremented by only 1. However, when I calibrated one of them
before
sending it to Agilent, (since I lost the data in the DALLAS CALRAM
chip that
I was removing) the CALNUM went from 1 to something like 34 or
something. I
don't recall. It seems that if you have the appropriate software to
run the
complete calibration protocol, it only increments by '1' instead of

all

the data points entered. Such software exists for the 3457A but I

never seen it available 'on theBay'. I suspect Agilent would have

software and equipment to do that calibration and, thus, an Agilent
calibration may only increment the CALNUM? by 1.

When getting an Agilent calibration of the 3458A, you get 'As
Received' and
'As Completed' data. Very helpful to me in that the only two points

'House CAL' of the one 3458A failed were the two 'midrange' AC

values. All else 'PASSED'.

I agree with Dave. If it's HP/Agilent, I prefer Agilent to do the

If

it's Solartron, I prefer AMETEK (Solartron), etc.

I believe that having some 'basic' professionally calibrated

instruments

(DMM's, Noise Sources, Power Sensors, Frequency Standards (unless

have a
GPSDO, CS Standard, etc.) etc.), that you can then use as 'transfer
standards' to do your own 'in house' calibration of other

is

very important if you want to set up a reliable workshop.

Of course, you will also need a 'stable' source of the various

signals

that
you will use to be 'measured' by the various 'DUT's', such as

resistance,

voltage, current, frequency, etc. The 3458A is relatively easy to
calibrate, requiring only 10.000000 VDC, 10000.000 ohms, and some AC
voltage
at various frequencies, IIRC. I have never CAL'd a 3457A but the

3478A

is a
multi-step process.

This whole thing can become very 'addictive'. Be careful.

Joe

-----Original Message-----
From: hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
[mailto:hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>] On Behalf Of David

Kirkby

Sent: Saturday, December 29, 2012 5:53 PM
To: hp_agilent_equipment@...

<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
<mailto:hp_agilent_equipment%40yahoogroups.com>

<mailto:hp_agilent_equipment%40yahoogroups.com>
Subject: Re: [hp_agilent_equipment] 3457a on the way

On 29 December 2012 20:01, Jeff Machesky <jeff@...

<mailto:jeff%40codebest.com>

<mailto:jeff%40codebest.com>
<mailto:jeff%40codebest.com>

<mailto:jeff%40codebest.com>
<mailto:jeff%40codebest.com> > wrote:

Thanks Dave, I actually have watched those videos. Bit drawn out

like

most of his videos..but still good. Too much detail is not always

bad

thing.

I thought the bit showing the noise on the DVM was a bit silly when

was connected to a DC power supply.

As for the 3457A, if it works I plan on getting it calibrated by

Agilent

within the year. From what I understand it's about a $200 US

investment.

The meter was last calibrated in '98, so I'll be curious to see

accurate it is when I get it.

I think the calibration service you chose might dictate whether you
get data about the condition when sent.

When I send mine in for cal, I'd like to know what was out and by

much. But I'm not going to pay extra for a calibration service that
provides that. As far as I'm concerned, if Agilent calibrate it,

it is OK. For me personally, it makes no difference whatsoever if it
has ISO, NIST or whatever calibration. But I'd prefer Agilent to
someone else.

I have calibration certificate here for an Agilent VNA calibration
kit. It was done by a calibration house in the USA. But from what I
can gather from reading the documentation, the equipment to

them is not available commerically. So it makes me wonder how a lab
can calibrate a cal kit, when the equipment to do it can't be

I suspect there is a fairly cosy realationship between some test
equipment dealers and calibration facilities.

I plan on purchasing some
voltage references from the well known site as a basic test of the
3457A. I may even calibrate it based on those references if it's

out

and later getting it NIST traceable calibrated.

I don't know if there are pots in there you can adjust with a

or if it is all done electronically. You might find it is impossible
to calibrate yourself.

I never had any reason to look inside mine.

Dave

------------------------------------

Yahoo! Groups Links

Chuck,

The random sampling is intentional and is done to reduce the artifacts of
precisely spaced samples.

I think the 3T77A was the first of Tek's attempts. I clearly remember that
one of the 3 Series sampling sweeps was labeled that way.

-John

================

David wrote:

There are many ways to get a waveform using sampling. All of those

that sample waveforms that are higher bandwidth than the sampling rate
are storing only small parts of many, many, repetitions of the signal
under test. In the case of the 7D20, and the 7854, you may be looking
at snippets of hundreds of repetitions of that signal, just to get a
look
at a single copy. In the days of old, these were called sampling
oscilloscopes.

My old Tektronix catalogs always refer to them as digitizers or
digital storage oscilloscopes. The term sampling was always
associated with instruments that had actual sampling front ends.

It doesn't matter what they call it, if it can't store the whole
waveform in one shot, it is a sampling scope, just as sure as the
old N, 1SXX, 7SXX, etc. plugins were. The prime difference is the
old type N, 1SXX, and 7Sxx plugins used the screen's phosphor, in
combination with the refresh rate, to "store" the sampled bits long
enough for you to see the full waveform. The 7D20, and 7854 use
digital storage bins, filled in a fairly chaotic way, to store the
sampled bits for view. If you have ever watched a 7854 store a
400MHz sine wave using its 50K sampling rate, you know what I mean.
If you have it set to display the stored bits as they come in, you
will see dots randomly appear on the screen (like snowflakes) as
the waveform is generated in the digital memory.

I never picked up a 7D20 because it lacks peak detection but the slow
waveform regeneration rate of my 2230 has only rarely been a problem.

I use a 7854, or a 7D20, quite a lot... but only in the single shot
mode. I usually only need storage to handle things that are slower
than my visual refresh rate.

-Chuck Harris

It was almost certainly a 2230 (100 MHz and 20 MS/sec) or 2220 (60 MHz
and 20 MS/sec) which came out in 1986 or at least first showed up in
that year's catalog.

The sample clock is not dithered but instead the difference between
the trigger and sample clock is measured to within about 500ps which
allows the acquired samples to be positioned within the waveform
record. In order to gain anything from that process, the signal being
measured and the sample clock have to be asynchronous.

It is my most used oscilloscope although the updated version in the
form of the 2232 is superior in almost every way.

On Mon, 31 Dec 2012 17:40:05 -0000, "erich_schlecht"
<schlechtca@...> wrote:

Speaking of old scopes, the first digital scope I got circa 1986 was a Tek with a sample rate around 20 or 50 Msps, bandwidth 100 or 200 MHz. For repetitive signals it dithered the sample clock to reconstruct signals well above the Nyquist frequency over many cycles. It couldn't see fast single event signals, of course.

It also had a pure analog mode. For the time, it was a pretty decent instrument.Unfortunately, I've long forgotten the model number, but it looked like a 24xx series.

Erich

--- In hp_agilent_equipment@..., Chuck Harris <cfharris@> wrote:

Hi Peter,

As I said, "any competently designed DSO". An analog scope gives
you the full vertical bandwidth regardless of the timebase setting.
A competently designed DSO should also.

You can be a bit flexible about that requirement, though. If the
aliasing effects are too fast to see at a particular timebase
setting, it would be ok to slow the sample rate until they are
only marginally too fast to see.

-Chuck Harris

Peter Gottlieb wrote:

But it's not just filtering above the Nyquist. There are other ways a sampling
digital scope can give you a wrong picture of reality. If all of these scopes
ran their digitizers constantly at full rate, watched for envelope effects and
so forth they would go a long way towards eliminating these unwanted erroneous
displays.

Peter


On 12/31/2012 10:56 AM, Chuck Harris wrote:

If by "trust" you mean see things faster than the Nyquist
limit, I fully agree.

We introduced the 2230 world-wide in the fall of 1985, so 1986 was the big year for it. It has equivalent-time sampling for display of repetitive signals up to 100 MHz, and peak detection for anti-aliasing envelope display of undersampled signals, and it operates in regular analog scope mode - equivalent to the 2235, which it was based on. The 2220 was the same, but lesser BW to fill the lower market spot. The 2232 followed, with many improvements - especially 100 Ms/sec sampling rate.

Ed

--- In hp_agilent_equipment@..., David <davidwhess@> wrote:

It was almost certainly a 2230 (100 MHz and 20 MS/sec) or 2220 (60 MHz
and 20 MS/sec) which came out in 1986 or at least first showed up in
that year's catalog.

The sample clock is not dithered but instead the difference between
the trigger and sample clock is measured to within about 500ps which
allows the acquired samples to be positioned within the waveform
record. In order to gain anything from that process, the signal being
measured and the sample clock have to be asynchronous.

It is my most used oscilloscope although the updated version in the
form of the 2232 is superior in almost every way.

On Mon, 31 Dec 2012 17:40:05 -0000, "erich_schlecht"
<schlechtca@> wrote:

Speaking of old scopes, the first digital scope I got circa 1986 was a Tek with a sample rate around 20 or 50 Msps, bandwidth 100 or 200 MHz. For repetitive signals it dithered the sample clock to reconstruct signals well above the Nyquist frequency over many cycles. It couldn't see fast single event signals, of course.

It also had a pure analog mode. For the time, it was a pretty decent instrument.Unfortunately, I've long forgotten the model number, but it looked like a 24xx series.

Erich

--- In hp_agilent_equipment@..., Chuck Harris <cfharris@> wrote:

Hi Peter,

As I said, "any competently designed DSO". An analog scope gives
you the full vertical bandwidth regardless of the timebase setting.
A competently designed DSO should also.

You can be a bit flexible about that requirement, though. If the
aliasing effects are too fast to see at a particular timebase
setting, it would be ok to slow the sample rate until they are
only marginally too fast to see.

-Chuck Harris

Peter Gottlieb wrote:

But it's not just filtering above the Nyquist. There are other ways a sampling
digital scope can give you a wrong picture of reality. If all of these scopes
ran their digitizers constantly at full rate, watched for envelope effects and
so forth they would go a long way towards eliminating these unwanted erroneous
displays.

Peter


On 12/31/2012 10:56 AM, Chuck Harris wrote:

If by "trust" you mean see things faster than the Nyquist
limit, I fully agree.

Chuck,

The random sampling is intentional and is done to reduce the artifacts of
precisely spaced samples.

I think the 3T77A was the first of Tek's attempts. I clearly remember that
one of the 3 Series sampling sweeps was labeled that way.

-John

================

David wrote:

There are many ways to get a waveform using sampling. All of those

that sample waveforms that are higher bandwidth than the sampling rate
are storing only small parts of many, many, repetitions of the signal
under test. In the case of the 7D20, and the 7854, you may be looking
at snippets of hundreds of repetitions of that signal, just to get a
look
at a single copy. In the days of old, these were called sampling
oscilloscopes.

My old Tektronix catalogs always refer to them as digitizers or
digital storage oscilloscopes. The term sampling was always
associated with instruments that had actual sampling front ends.

It doesn't matter what they call it, if it can't store the whole
waveform in one shot, it is a sampling scope, just as sure as the
old N, 1SXX, 7SXX, etc. plugins were. The prime difference is the
old type N, 1SXX, and 7Sxx plugins used the screen's phosphor, in
combination with the refresh rate, to "store" the sampled bits long
enough for you to see the full waveform. The 7D20, and 7854 use
digital storage bins, filled in a fairly chaotic way, to store the
sampled bits for view. If you have ever watched a 7854 store a
400MHz sine wave using its 50K sampling rate, you know what I mean.
If you have it set to display the stored bits as they come in, you
will see dots randomly appear on the screen (like snowflakes) as
the waveform is generated in the digital memory.

I never picked up a 7D20 because it lacks peak detection but the slow
waveform regeneration rate of my 2230 has only rarely been a problem.

I use a 7854, or a 7D20, quite a lot... but only in the single shot
mode. I usually only need storage to handle things that are slower
than my visual refresh rate.

-Chuck Harris

Yeah !
IMHO this instrument was THE great successor of the legendary 465: easy to use (except menus) and exceptional & reliable readings due to the top performance "peak-det" feature implemented in this very instrument. I used most the digital mode because it was so trustable! After many years I sold it for more recent models. And finally missed it and bought a used 2232 which featured many nice improvements over the former. This one is now my prefered general purpose workhorse among three others (2440, 2467BHD & HP 54542A). A friend of mine which I adviced to buy a 2232 said that this was really what he long awaited for...

Congrats for the great job! I suspect later scopes were not designed by the same team... Right ?

Christian F1GWR


Le 1 janv. 2013 à 04:39, "Ed Breya" <edbreya@...> a écrit :

We introduced the 2230 world-wide in the fall of 1985, so 1986 was the big year for it. It has equivalent-time sampling for display of repetitive signals up to 100 MHz, and peak detection for anti-aliasing envelope display of undersampled signals, and it operates in regular analog scope mode - equivalent to the 2235, which it was based on. The 2220 was the same, but lesser BW to fill the lower market spot. The 2232 followed, with many improvements - especially 100 Ms/sec sampling rate.

Ed

In order to use a HP 8757A SNA as a display, the noise figure meter 8970B

My datecode is only 2725 yelding E36 error. Bad luck!
To display firmware release enter 99.9 SP on the 8970B.
If someone could provide me with related ROM dump, would be great!

David wrote:

There are many ways to get a waveform using sampling. All of those

that sample waveforms that are higher bandwidth than the sampling rate
are storing only small parts of many, many, repetitions of the signal
under test. In the case of the 7D20, and the 7854, you may be looking
at snippets of hundreds of repetitions of that signal, just to get a
look
at a single copy. In the days of old, these were called sampling
oscilloscopes.

My old Tektronix catalogs always refer to them as digitizers or
digital storage oscilloscopes. The term sampling was always
associated with instruments that had actual sampling front ends.

It doesn't matter what they call it, if it can't store the whole
waveform in one shot, it is a sampling scope, just as sure as the
old N, 1SXX, 7SXX, etc. plugins were. The prime difference is the
old type N, 1SXX, and 7Sxx plugins used the screen's phosphor, in
combination with the refresh rate, to "store" the sampled bits long
enough for you to see the full waveform. The 7D20, and 7854 use
digital storage bins, filled in a fairly chaotic way, to store the
sampled bits for view. If you have ever watched a 7854 store a
400MHz sine wave using its 50K sampling rate, you know what I mean.
If you have it set to display the stored bits as they come in, you
will see dots randomly appear on the screen (like snowflakes) as
the waveform is generated in the digital memory.

I never picked up a 7D20 because it lacks peak detection but the slow
waveform regeneration rate of my 2230 has only rarely been a problem.

I use a 7854, or a 7D20, quite a lot... but only in the single shot
mode. I usually only need storage to handle things that are slower
than my visual refresh rate.

-Chuck Harris

You're probably thinking of a 2232. The 24xx digital series have no analog
mode.

--- In hp_agilent_equipment@..., Yuting Wan <ywan03@...>
wrote:

Modern DSO has much higher sampling rate, called over sampling. I

remember I read this in the 90s oversampling can greatly eliminate the
phase distortion caused by a stiff anti-aliasing filter, instead a more
relaxed filter is used under oversampling.

Tim
On 01/01/2013, at 4:40 AM, erich_schlecht wrote:

Speaking of old scopes, the first digital scope I got circa 1986 was a

Tek with a sample rate around 20 or 50 Msps, bandwidth 100 or 200 MHz. For
repetitive signals it dithered the sample clock to reconstruct signals well
above the Nyquist frequency over many cycles. It couldn't see fast single
event signals, of course.

It also had a pure analog mode. For the time, it was a pretty decent

instrument.Unfortunately, I've long forgotten the model number, but it
looked like a 24xx series.

Erich

------------------------------------

Yahoo! Groups Links

Modern DSO has much higher sampling rate, called over sampling. I remember I read this in the 90s oversampling can greatly eliminate the phase distortion caused by a stiff anti-aliasing filter, instead a more relaxed filter is used under oversampling.

Tim
On 01/01/2013, at 4:40 AM, erich_schlecht wrote:

Speaking of old scopes, the first digital scope I got circa 1986 was a Tek with a sample rate around 20 or 50 Msps, bandwidth 100 or 200 MHz. For repetitive signals it dithered the sample clock to reconstruct signals well above the Nyquist frequency over many cycles. It couldn't see fast single event signals, of course.

It also had a pure analog mode. For the time, it was a pretty decent instrument.Unfortunately, I've long forgotten the model number, but it looked like a 24xx series.

Erich

Speaking of old scopes, the first digital scope I got circa 1986 was a Tek with a sample rate around 20 or 50 Msps, bandwidth 100 or 200 MHz. For repetitive signals it dithered the sample clock to reconstruct signals well above the Nyquist frequency over many cycles. It couldn't see fast single event signals, of course.

It also had a pure analog mode. For the time, it was a pretty decent instrument.Unfortunately, I've long forgotten the model number, but it looked like a 24xx series.

Erich

--- In hp_agilent_equipment@..., Chuck Harris <cfharris@...> wrote:

Hi Peter,

As I said, "any competently designed DSO". An analog scope gives
you the full vertical bandwidth regardless of the timebase setting.
A competently designed DSO should also.

You can be a bit flexible about that requirement, though. If the
aliasing effects are too fast to see at a particular timebase
setting, it would be ok to slow the sample rate until they are
only marginally too fast to see.

-Chuck Harris

Peter Gottlieb wrote:

But it's not just filtering above the Nyquist. There are other ways a sampling
digital scope can give you a wrong picture of reality. If all of these scopes
ran their digitizers constantly at full rate, watched for envelope effects and
so forth they would go a long way towards eliminating these unwanted erroneous
displays.

Peter


On 12/31/2012 10:56 AM, Chuck Harris wrote:

If by "trust" you mean see things faster than the Nyquist
limit, I fully agree.

I recall Lothar telling me several years ago that these O-rings were available for watch repair. -Eric

--- In hp_agilent_equipment@..., Steve Krull <Steve-Krull@> wrote:

I've got an attenuator for an 8672A that suffers from failed O-rings. In
this case it appears someone used something nasty to try to clean the
spring contacts and attenuator pads and whatever was used dripped down
the nylon plungers and turned all the O-rings to a mushy black paste.
Not a single survivor. Agilent no longer stocks them but provides the
dimensions and material type so I just need to research a source.

Steve

I've got an attenuator for an 8672A that suffers from failed O-rings. In
this case it appears someone used something nasty to try to clean the
spring contacts and attenuator pads and whatever was used dripped down
the nylon plungers and turned all the O-rings to a mushy black paste.
Not a single survivor. Agilent no longer stocks them but provides the
dimensions and material type so I just need to research a source.

Steve