Re: Oscilloscopes - analog but with digital capability?
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
================
toggle quoted message
Show quoted text
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
|
Re: Oscilloscopes - analog but with digital capability?
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
|
Re: Oscilloscopes - analog but with digital capability?
Does anyone know where I can get a Tek 2232 with either the GPIB/HP-IB or
RS-232 option? I don't see any with those options on ebay at the moment;
were these interfaces uncommon or something?
Thanks
toggle quoted message
Show quoted text
On Tue, Jan 1, 2013 at 9:43 AM, victor.silva <daejon1@...> wrote: 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
|
Re: Oscilloscopes - analog but with digital capability?
You're probably thinking of a 2232. The 24xx digital series have no analog mode.
toggle quoted message
Show quoted text
--- 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
|
Re: Oscilloscopes - analog but with digital capability?
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
toggle quoted message
Show quoted text
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
--- 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.
|
Re: Oscilloscopes - analog but with digital capability?
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
[Non-text portions of this message have been removed]
|
Thank you Ed. I am aware of the Hittite parts. Up the reference 20% and divide by 8 works. I will be a happy camper. Eric _____ From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...] On Behalf Of Ed Breya Sent: Monday, December 31, 2012 9:10 PM To: hp_agilent_equipment@... Subject: [hp_agilent_equipment] Re: HP 5385A Advice Check out Hittite for fast dividers. You may find that dividing by eight is more acceptible considering that at such high frequencies, binary dividing is much easier than any other number. You can prescale by any divider ratio and still get correct numeric results by scaling the counter clock in proportion. An alternative is to subtract frequencies instead - simple if the desired counting range is fairly small. Ed --- In hp_agilent_equipment@... <mailto:hp_agilent_equipment%40yahoogroups.com> , "Erick Schumacher" <wb6kcn@...> wrote:
Hi Folks
Anybody have any advice on getting a decade divider to go in front of a
5385 counter so I can measure frequencies around X band. Divide by 8 is not
acceptable. Clugey is acceptable as long as it is cheap.
Eric
|
Re: DIY: Repair of HP 8568B Step Attenuators - another question...
All the products that use this part.
a.. 11758V
a.. 33320G
a.. 33320H
a.. 33321H
a.. 33322Q
a.. 3708A
a.. 70904A
a.. 70907B-H10
a.. 70908A-H10
a.. 70908A-H25
a.. 71100C
a.. 71100P
a.. 71210P
a.. 71400C
a.. 71401C
a.. 8340B
a.. 83810B
a.. 84100EM
a.. 84110EM
a.. 84125A
a.. 84125B
a.. 84300A-E53
a.. 84300A-E57
a.. 84300A-E95
a.. 8494G
a.. 8494H
a.. 8495H
a.. 8496G
a.. 85070M
a.. 8514B
a.. 8515A
a.. 85301B
a.. 85301C
a.. 8542E
a.. 8546A
a.. 8590L
a.. 8590L-R13
a.. 8591EM
a.. 8593E
a.. 86030A
a.. 86037A
a.. 86037B
a.. 86037C
a.. 8642B
a.. 8662A
a.. 8664A
a.. 8665A
a.. 8665B
a.. 8672A
a.. 86794B
a.. 8752C
a.. 8753D
a.. 8753E
a.. 8753ES
a.. 8902A
a.. E2500B
a.. E2500B-508
a.. E2505A
a.. E2507B
a.. E2508A
a.. E2747A-003
a.. E4901B
a.. E4902B
a.. E5501A
a.. E5501B
a.. E5502B
a.. E5503A
a.. E5503B
a.. E5504A
a.. E5504B
a.. E7350A
a.. Z5200FB
toggle quoted message
Show quoted text
----- Original Message -----
From: johncharlesgord
To: hp_agilent_equipment@...
Sent: Tuesday, January 01, 2013 1:20 AM
Subject: [hp_agilent_equipment] Re: DIY: Repair of HP 8568B Step Attenuators - another question...
For a picture of the plastic rod with attached o-rings, lookup 5060-0342 at parts.agilent.com. I bought some back in September, but they are apparently only available to Agilent inside operations now.
Unfortunately, it is difficult (for me, anyway) to remove the rods for o-ring replacement without damaging them. It made sense that they were sold as a combined unit.
--John Gord
--- In hp_agilent_equipment@..., "Eric" <eric_haskell@...> wrote:
>
> 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
> >
>
|
Re: DIY: Repair of HP 8568B Step Attenuators - another question...
For a picture of the plastic rod with attached o-rings, lookup 5060-0342 at parts.agilent.com. I bought some back in September, but they are apparently only available to Agilent inside operations now.
Unfortunately, it is difficult (for me, anyway) to remove the rods for o-ring replacement without damaging them. It made sense that they were sold as a combined unit.
--John Gord
toggle quoted message
Show quoted text
--- In hp_agilent_equipment@..., "Eric" <eric_haskell@...> wrote:
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
|
Re: DIY: Repair of HP 8568B Step Attenuators - another question...
I recall Lothar telling me several years ago that these O-rings were available for watch repair. -Eric
toggle quoted message
Show quoted text
--- 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
|
Check out Hittite for fast dividers. You may find that dividing by eight is more acceptible considering that at such high frequencies, binary dividing is much easier than any other number. You can prescale by any divider ratio and still get correct numeric results by scaling the counter clock in proportion.
An alternative is to subtract frequencies instead - simple if the desired counting range is fairly small.
Ed
toggle quoted message
Show quoted text
--- In hp_agilent_equipment@..., "Erick Schumacher" <wb6kcn@...> wrote:
Hi Folks
Anybody have any advice on getting a decade divider to go in front of a 5385
counter so I can measure frequencies around X band. Divide by 8 is not
acceptable. Clugey is acceptable as long as it is cheap.
Eric
|
Hi Folks
Anybody have any advice on getting a decade divider to go in front of a 5385
counter so I can measure frequencies around X band. Divide by 8 is not
acceptable. Clugey is acceptable as long as it is cheap.
Eric
|
HP859x LODA Gate Bias adjustment
Hi All,
Happy new year to everyone.
I have a 8593E that has a Local un-level issue. While checking the LODA Gate Bias using the service level procedure, the DMM reading was around -1.29V and all over the place by as much as several hundred millivolts.
The RF assembly Gate bias sticker states -700mv, I adjusted R29 as stated and the GB level can be adjusted down to the desired -700mv, however the voltage is still quite unstable, again as much as +/- 100mv, whereas the process states that the adjustment must be within 5mv.
I have never worked on any 859x series SA before,, could this symptom be a power supply issue, or is there a more sinister/serious non serviceable fault?
Would anyone have recently checked the LODA GB voltage?
The Analyser functionally works very well. However a basic phase noise measurement using John's GPIB toolkit showed a serious measurement error compared to my HP8560E using both internal ref signals.
Thank you in advance.
Regards
Gerald
VK3GJM
|
Mouser appears to have these batteries for $5.xx US. Actually searching around it appears a bunch of places have them. BR 2/3A. I wouldn't get one that I even slightly questioned it's freshness. Newark also appears to have them and I'm sure Digikey.
Thanks,
Jeff
toggle quoted message
Show quoted text
On 12/31/2012 8:34 PM, Steve wrote:
That looks very close to what's in mine. Their warranty is only against DOA. I wonder how old their batteries are...
Steve
On Dec 31, 2012, at 7:53 PM, Peter Gottlieb <hpnpilot@... <mailto:hpnpilot%40verizon.net>> wrote:
Like this one:?
I shouldn't imagine there's much special about these except the
physical size.
On 12/31/2012 7:25 PM, J. L. Trantham wrote:
Steve, Jeff, and all,
My 2703Axxxxx 3457A also has the SAFT LX 1634, Lithium 3.0V,
battery and it
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'
resistors
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 a
'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 should
be used?
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
Krull
Sent: Monday, December 31, 2012 11:20 AM
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
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%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 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>
<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 Boeing
Military Airplane Company's metrology lab. I need to open it up
and check
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>
<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%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>
<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>
<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 for
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
goods.
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 then
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 be
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
manual.
Interestingly, when I sent my two 3458A's to Agilent for
calibration,
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 by
all
the data points entered. Such software exists for the 3457A but
I have
never seen it available 'on theBay'. I suspect Agilent would
have that
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 my
'House CAL' of the one 3458A failed were the two 'midrange' AC
Voltage
values. All else 'PASSED'.
I agree with Dave. If it's HP/Agilent, I prefer Agilent to do
the CAL.
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 you
have a
GPSDO, CS Standard, etc.) etc.), that you can then use as 'transfer
standards' to do your own 'in house' calibration of other
instruments,
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%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>
<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>
<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>
<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 a
bad
thing. I thought the bit showing the noise on the DVM was a bit silly
when it
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 how
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 how
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,
then
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
calibrate
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
bought.
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 way
out
and later getting it NIST traceable calibrated. I don't know if there are pots in there you can adjust with a
trimmer,
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
----------------------------------------------------------
No virus found in this message.
Checked by AVG - www.avg.com <>
Version: 10.0.1430 / Virus Database: 2637/5500 - Release Date: 12/31/12
------------------------------------
Yahoo! Groups Links
|
Re: Oscilloscopes - analog but with digital capability?
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
toggle quoted message
Show quoted text
--- 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.
|
That looks very close to what's in mine. Their warranty is only against DOA. I wonder how old their batteries are...
Steve
toggle quoted message
Show quoted text
On Dec 31, 2012, at 7:53 PM, Peter Gottlieb <hpnpilot@...> wrote: Like this one:?
I shouldn't imagine there's much special about these except the physical size.
On 12/31/2012 7:25 PM, J. L. Trantham wrote:
Steve, Jeff, and all,
My 2703Axxxxx 3457A also has the SAFT LX 1634, Lithium 3.0V, battery and it
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' resistors
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 a
'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 should
be used?
Joe
-----Original Message-----
From: hp_agilent_equipment@...
<mailto:hp_agilent_equipment%40yahoogroups.com>
[mailto:hp_agilent_equipment@...
<mailto:hp_agilent_equipment%40yahoogroups.com>] On Behalf Of Steve Krull
Sent: Monday, December 31, 2012 11:20 AM
To: hp_agilent_equipment@...
<mailto:hp_agilent_equipment%40yahoogroups.com>
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%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 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>
<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 Boeing
Military Airplane Company's metrology lab. I need to open it up and check
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>
<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%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 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>
<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 for
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 goods.
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 then
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 be
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 manual.
Interestingly, when I sent my two 3458A's to Agilent for calibration,
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 by
all
the data points entered. Such software exists for the 3457A but I have
never seen it available 'on theBay'. I suspect Agilent would have that
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 my
'House CAL' of the one 3458A failed were the two 'midrange' AC Voltage
values. All else 'PASSED'.
I agree with Dave. If it's HP/Agilent, I prefer Agilent to do the CAL.
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 you
have a
GPSDO, CS Standard, etc.) etc.), that you can then use as 'transfer
standards' to do your own 'in house' calibration of other instruments,
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%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>
<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>
<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>
<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 a
bad
thing. I thought the bit showing the noise on the DVM was a bit silly when it
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 how
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 how
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, then
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 calibrate
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 bought.
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 way
out
and later getting it NIST traceable calibrated. I don't know if there are pots in there you can adjust with a trimmer,
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
[Non-text portions of this message have been removed]
------------------------------------
Yahoo! Groups Links
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
--------------------------------------------------------------------------------
No virus found in this message.
Checked by AVG - www.avg.com <>
Version: 10.0.1430 / Virus Database: 2637/5500 - Release Date: 12/31/12
------------------------------------
Yahoo! Groups Links
|
Hmmm, I just hit Wikipedia.
A CR 2/3 AA might do the trick. They are 3 volt lithium's. Varta 6237 or CR14335. 3.4 volts hmmm, Li-Phosphate is the closest at 3.3 volts. LiPo is 3.7 volts. Info from
My Tek 2465 has a Dallas chip with potted battery. I had to drill a micro hole to test the voltage. Then I replaced it and lost all the cal data trying to remove it. The PCB came out of the ordeal looking spotless...the Dallas chip..not so much. Past tense, all is well now.
Thanks,
Jeff
toggle quoted message
Show quoted text
On 12/31/2012 6:53 PM, Peter Gottlieb wrote: Like this one:?
I shouldn't imagine there's much special about these except the physical size.
On 12/31/2012 7:25 PM, J. L. Trantham wrote:
Steve, Jeff, and all,
My 2703Axxxxx 3457A also has the SAFT LX 1634, Lithium 3.0V, battery and it
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' resistors
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 a
'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 should
be used?
Joe
-----Original Message-----
From: hp_agilent_equipment@...
<mailto:hp_agilent_equipment%40yahoogroups.com>
[mailto:hp_agilent_equipment@...
<mailto:hp_agilent_equipment%40yahoogroups.com>] On Behalf Of Steve Krull
Sent: Monday, December 31, 2012 11:20 AM
To: hp_agilent_equipment@...
<mailto:hp_agilent_equipment%40yahoogroups.com>
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%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 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>
<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 Boeing
Military Airplane Company's metrology lab. I need to open it up and check
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>
<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%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 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>
<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 for
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 goods.
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 then
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 be 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 manual.
Interestingly, when I sent my two 3458A's to Agilent for calibration,
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 by
all
the data points entered. Such software exists for the 3457A but I have
never seen it available 'on theBay'. I suspect Agilent would have that
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 my
'House CAL' of the one 3458A failed were the two 'midrange' AC Voltage
values. All else 'PASSED'.
I agree with Dave. If it's HP/Agilent, I prefer Agilent to do the CAL.
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 you
have a
GPSDO, CS Standard, etc.) etc.), that you can then use as 'transfer
standards' to do your own 'in house' calibration of other instruments,
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%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>
<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>
<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>
<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 a
bad
thing. I thought the bit showing the noise on the DVM was a bit silly when it
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 how
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 how
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, then
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 calibrate
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 bought.
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 way
out
and later getting it NIST traceable calibrated. I don't know if there are pots in there you can adjust with a trimmer,
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
--------------------------------------------------------------------------------
No virus found in this message.
Checked by AVG - www.avg.com <>
Version: 10.0.1430 / Virus Database: 2637/5500 - Release Date: 12/31/12
------------------------------------
Yahoo! Groups Links
|
Re: Oscilloscopes - analog but with digital capability?
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.
|
Like this one:?
I shouldn't imagine there's much special about these except the physical size.
toggle quoted message
Show quoted text
On 12/31/2012 7:25 PM, J. L. Trantham wrote:
Steve, Jeff, and all,
My 2703Axxxxx 3457A also has the SAFT LX 1634, Lithium 3.0V, battery and it
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' resistors
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 a
'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 should
be used?
Joe
-----Original Message-----
From: hp_agilent_equipment@... <mailto:hp_agilent_equipment%40yahoogroups.com>
[mailto:hp_agilent_equipment@... <mailto:hp_agilent_equipment%40yahoogroups.com>] On Behalf Of Steve Krull
Sent: Monday, December 31, 2012 11:20 AM
To: hp_agilent_equipment@... <mailto:hp_agilent_equipment%40yahoogroups.com>
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%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 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>
<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 Boeing
Military Airplane Company's metrology lab. I need to open it up and check
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>
<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%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 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>
<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 for
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 goods.
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 then
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 be
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 manual.
Interestingly, when I sent my two 3458A's to Agilent for calibration,
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 by
all
the data points entered. Such software exists for the 3457A but I have
never seen it available 'on theBay'. I suspect Agilent would have that
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 my
'House CAL' of the one 3458A failed were the two 'midrange' AC Voltage
values. All else 'PASSED'.
I agree with Dave. If it's HP/Agilent, I prefer Agilent to do the CAL.
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 you
have a
GPSDO, CS Standard, etc.) etc.), that you can then use as 'transfer
standards' to do your own 'in house' calibration of other instruments,
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%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>
<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>
<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>
<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 a
bad
thing. I thought the bit showing the noise on the DVM was a bit silly when it
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 how
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 how
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, then
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 calibrate
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 bought.
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 way
out
and later getting it NIST traceable calibrated. I don't know if there are pots in there you can adjust with a trimmer,
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
--------------------------------------------------------------------------------
No virus found in this message.
Checked by AVG - www.avg.com <>
Version: 10.0.1430 / Virus Database: 2637/5500 - Release Date: 12/31/12
|
Joe and all, I will pop the covers off mine again and have a look at the A1 board revision number and resistor values. Regarding battery voltage, I noticed a couple of web sites state that their lithium batteries are "3.6 v nominal, 3.4 volt operating" I assume that's at their rated current so HP may have been stating operating voltage. I can't imagine that maintaining cal constants would draw much current though. Steve On Dec 31, 2012, at 6:25 PM, "J. L. Trantham" <jltran@...> wrote: Steve, Jeff, and all,
My 2703Axxxxx 3457A also has the SAFT LX 1634, Lithium 3.0V, battery and it
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' resistors
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 a
'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 should
be used?
Joe
-----Original Message-----
From: hp_agilent_equipment@...
[mailto:hp_agilent_equipment@...] On Behalf Of Steve Krull
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 Boeing
Military Airplane Company's metrology lab. I need to open it up and check
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 for
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 goods.
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 then
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 be
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 manual.
Interestingly, when I sent my two 3458A's to Agilent for calibration,
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 by
all
the data points entered. Such software exists for the 3457A but I have
never seen it available 'on theBay'. I suspect Agilent would have that
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 my
'House CAL' of the one 3458A failed were the two 'midrange' AC Voltage
values. All else 'PASSED'.
I agree with Dave. If it's HP/Agilent, I prefer Agilent to do the CAL.
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 you
have a
GPSDO, CS Standard, etc.) etc.), that you can then use as 'transfer
standards' to do your own 'in house' calibration of other instruments,
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 a
bad
thing. I thought the bit showing the noise on the DVM was a bit silly when it
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 how
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 how
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, then
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 calibrate
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 bought.
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 way
out
and later getting it NIST traceable calibrated. I don't know if there are pots in there you can adjust with a trimmer,
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
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
|
Eric Schumacher
Eric Haskell [KC4YOE]
David Hess