Re: Oscilloscopes - analog but with digital capability?
Tektronix made a number of oscilloscopes like you describe including some interesting hybrids. Phillips made some oscilloscopes contemporary to the Tektronix 2232 series but supporting 4 channels, 200 MHz bandwidths, and with more features. I have avoided them because of the lack of service information. Here are the Tektronix analog oscilloscopes that include at least some form of digital storage roughly in order: The Tektronix P7001 attaches to a 7704A (200 MHz) between the display and mainframe: The Tektronix 7854 (400 MHz) works like a P7001 but is all one unit. It uses the analog timebase for digital storage which has the side effect of allowing equivalent time sampling without a clock delay timer. With a 7B87 timebase, it also supports low speed real time single shot captures with pretrigger. The user interface and programming make a great companion to your HP RPN calculator. The Tektronix 468 is a 465 (100 MHz) with a digitizer module (8 bits and 25 MS/sec) mounted on top. It apparently supports some type of equivalent time sampling called "jitter correction" in the manual but is still limited to a 10 MHz bandwidth in storage mode. The 2232 (100 MHz 100 MS/sec), 2224 (60 MHz and 100 MS/sec), and 2230 (100 MHz 20 MS/sec) support real time sampling, equivalent time sampling, and peak detection. The other 22xx series oscilloscopes operate with real time sampling only and no peak detection. The 2221A (100 MHz 100 MS/sec) and 2221 (100 MHz 20 MS/sec) are single timebase versions of the 2232 and 2230. My 2230 is my go to oscilloscope although if I need to backup waveforms for later, I use my 2232 instead because my 2230 does not have the memory backup option. The Tektronix 2252 is a 2247A (100 MHz 4 channels) with limited digital storage using sequential sampling. Some of the above oscilloscopes have much higher storage resolution than you would expect. The 2252 is 12 bits vertical. The 7854 is 10 bits horizontal and vertical. Of the above, the 2230 and 2232 are the most common and easiest to maintain. The 2221 and 2221A are just as easy to maintain because they are essentially the same as the 2230 and 2232. The 7854 is the most versatile but lacks real time operation and peak detection. On Sun, 30 Dec 2012 17:09:00 -0500, Bryce Schroeder <bryce.schroeder@...> wrote: Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this.
So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers?
Thanks for your time - sorry if that was a bit lengthy.
|
Re: Oscilloscopes - analog but with digital capability?
On Sun, 30 Dec 2012 14:40:09 -0800 (PST), you wrote: Yes.
The Tek DPO, based on the 7704 (or possibly the 7704A) was the first AFAIK. That would be the Tektronix 7D20 (as a combined timebase/dual channel scope) which was intended to run at least in the 760x series.
Then there was the magnificent 7854. IMO, this is the BEST lab 'scope
ever made. It is still my 'scope of choice.
and I'd like to have one, but that's still out there, somewhere..... The downfall of both of these units was the relatively slow A/D by modern
standards. 10 MHz bandwidth for the 468, and about 70 Mhz bandwidth for the 7D20 (IIRC).
There were also some Transient Data Digitizers that used specialized
double ended CRTs, I think.
That would be the 7912, IIRC, which used the 7B16P and 7B90P programmable plugins as a minimum. Never had one, but it looks like an interesting possibility to have. Harvey
-John
=============
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that
were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this.
So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers?
Thanks for your time - sorry if that was a bit lengthy.
|
Re: Oscilloscopes - analog but with digital capability?
On Sun, 30 Dec 2012 17:09:00 -0500, you wrote: Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this. Look at the Tek 468 scope. It had a digital backpack, capable of about 10 Mhz bandwidth. The processor was (IIRC) and 8051 style, with limited memory, etc. The basic scope was a 465, a 100 Mhz dual channel scope. The circuitry was an add-on backpack that could take over the display (without the processor running, the scope won't work). The amount of digital controls available were minimal, but allowed you to measure waveform extensions (amplitude) and timing conditions with several manually adjustable cursors. IIRC there was one memory. A more modern processor would allow much greater capability, and one of these days, I might just make a plugin to make that happen. If you look at the scope, there's a digital backpack with an add-on hood for the display, and an extension with the processor boards. The scope was capable of running the HPIB interface as a talker only. Other scopes, say in the 24xx series for Tektronix, are completely digital. Harvey
So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers?
Thanks for your time - sorry if that was a bit lengthy.
|
FS: Mint HP 8447D 0.1-1300MHz amplifier
Hi all.
I have a mint HP 8447D 0.1-1300MHz amplifier for sale. It is in full working condition and in good shape. It is excess to my needs and so selling it away.
Asking $250 plus shipping.
Pictures of the item:
..
Erik
|
Re: Oscilloscopes - analog but with digital capability?
HP 1980B has a digital sampler board used to store a waveform. It has a whole 501 points of resolution. This is an Analog scope with Digital controls. Very nice " AUTO-SCOPE " for it's age.
toggle quoted message
Show quoted text
--- In hp_agilent_equipment@..., Bryce Schroeder <bryce.schroeder@...> wrote:
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were
SNIP <
|
Tom, you may have a valid point. I'll have to look at the schematics. I think it's a bit safer however to use a battery substitution voltage then to have the entire instrument up and running. Heaven forbid something falls..etc.
Thanks,
Jeff
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On 12/30/2012 4:59 PM, Tom Miller wrote:
----- Original Message -----
From: "Jeff Machesky" <jeff@... <mailto:jeff%40codebest.com>>
To: <hp_agilent_equipment@... <mailto:hp_agilent_equipment%40yahoogroups.com>>
Sent: Sunday, December 30, 2012 2:31 PM
Subject: Re: [hp_agilent_equipment] Re: 3457a on the way
Todd, the battery is already on my list of to do items. The security
seal on the meter I've got on the way appears to have not been broken. I
assume this is from the last cal back in 98. The fact that it has a seal
on the case might be a sign that someone had done work internally,
perhaps just the offsets.
I have two options, check the battery and replace as needed when I get
the meter or wait until just before sending it off for cal knowing that
if I loose the cal data it's not the end of the world. I assume Agilent
isn't going to charge more because the cal data was lost? I think either
way I need to know what the voltage is of the battery and what type of
battery it is. Replacement of course would be done with a current
limited power source in place to act as the battery while it's being
changed. A bench supply with the voltage matched should do the trick.
I'm hoping it will already have the 3.4v battery to make my life a bit
easier. Not that I mind replacing a couple resistors.
Thanks,
Jeff
Why not just apply AC power while changing the battery. Just use an
ungrounded soldering iron.
Or is there some other thing I am not thinking about?
|
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Show quoted text
----- Original Message ----- From: "Jeff Machesky" <jeff@...> To: <hp_agilent_equipment@...> Sent: Sunday, December 30, 2012 2:31 PM Subject: Re: [hp_agilent_equipment] Re: 3457a on the way Todd, the battery is already on my list of to do items. The security
seal on the meter I've got on the way appears to have not been broken. I
assume this is from the last cal back in 98. The fact that it has a seal
on the case might be a sign that someone had done work internally,
perhaps just the offsets.
I have two options, check the battery and replace as needed when I get
the meter or wait until just before sending it off for cal knowing that
if I loose the cal data it's not the end of the world. I assume Agilent
isn't going to charge more because the cal data was lost? I think either
way I need to know what the voltage is of the battery and what type of
battery it is. Replacement of course would be done with a current
limited power source in place to act as the battery while it's being
changed. A bench supply with the voltage matched should do the trick.
I'm hoping it will already have the 3.4v battery to make my life a bit
easier. Not that I mind replacing a couple resistors.
Thanks,
Jeff
Why not just apply AC power while changing the battery. Just use an ungrounded soldering iron. Or is there some other thing I am not thinking about?
|
Re: HP 8970B firmware v2800+ wanted
Christian,
I have an 8970B, SN 2947Axxxxx, OPT H18, and when I enter '99.9 Special
Function', I get '08844' in the left hand display.
When I enter '47.1 Special Function', I get no errors.
Is this what you need? If so, I can open the unit, read the EPROM's, and
send you the data.
Joe
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-----Original Message----- From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...] On Behalf Of f1gwr Sent: Sunday, December 30, 2012 3:54 PM To: hp_agilent_equipment@... Subject: [hp_agilent_equipment] HP 8970B firmware v2800+ wanted
In order to use a HP 8757A SNA as a display, the noise figure meter 8970B
requests version 2800 at least to enable special functions 47.x as described in Product Note 8970B/S-4. 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!
Almost two years ago I posted the above message, but till now did not get suitable answer. Maybe someone could read a recent ROM and post it? Please note K04BB's site only holds 2705 version of the firmware ROM, see: )_ROM_Images_and_Drivers/HP_8970B So I'm looking for 2800 release or later. Thanks for your help, Christian
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Re: Oscilloscopes - analog but with digital capability?
The 7854 does take some learning, especially if you want to use the
keyboard functions.
BTW, a 7B53A is not the correct PI as a sweep. It is a sweep for something
like a 7603 or other 100 MHz mainframes.
The 7854 is a 400 MHz mainframe. The proper sweeps for the 7854 are the
7B80 & 7B85 or the 7B92A.
To use the digitizing functions properly, you need the 7B87.
-John
===============
toggle quoted message
Show quoted text
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that
were
basically analog scopes, but with the ability to digitize what is seen
on
the display (at some lesser resolution than what you might be able to
see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort
of
like this. So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the
screen
and see the waveform displayed like an analog scope, or use the ADC to
see
a digital approximation. (Presumably the digital stuff could also be
used
to capture and store one-shot things like a regular digital
oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display. The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the
digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans. Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers? Thanks for your time - sorry if that was a bit lengthy.
30/12/2012 23:27
I am lucky enough to have both the Fluke / Philips Combiscope and a
Tek 7854. The Combiscope is, in my humble opinion, greatly under rated.
It's so easy to use, small and relatively light, and my 2 channel
model has been 100% reliable. If it packed up I'd look for another. It
does look very "full" inside, and it does run very warm, as another
poster commented.
The 7854 is huge, heavy, dims the lights on power up, and I only
understand and use a fraction of it's abilities. The manual is vast,
and quite daunting to a casual user. It's saving grace is awesome
support on the Tek scopes' reflectors. If it does pack up there are
those able to help you fix it. I also like the availability of cheap
plug ins. I bought a sad and ratty looking 7B53A dual time base with
delay for next to nowt off the `Bay, and with the help of the forum
had it fixed up and calibrated inside a few hours. Must have been a
fabulous beast in its day, even now USB scope users see it and go off
wanting a "proper" scope unless they have spent a fortune on something
VERY high end.
--
Best Regards,
Chris Wilson.
------------------------------------
Yahoo! Groups Links
|
Re: Oscilloscopes - analog but with digital capability?
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this. So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display. The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans. Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers? Thanks for your time - sorry if that was a bit lengthy. 30/12/2012 23:27 I am lucky enough to have both the Fluke / Philips Combiscope and a Tek 7854. The Combiscope is, in my humble opinion, greatly under rated. It's so easy to use, small and relatively light, and my 2 channel model has been 100% reliable. If it packed up I'd look for another. It does look very "full" inside, and it does run very warm, as another poster commented. The 7854 is huge, heavy, dims the lights on power up, and I only understand and use a fraction of it's abilities. The manual is vast, and quite daunting to a casual user. It's saving grace is awesome support on the Tek scopes' reflectors. If it does pack up there are those able to help you fix it. I also like the availability of cheap plug ins. I bought a sad and ratty looking 7B53A dual time base with delay for next to nowt off the `Bay, and with the help of the forum had it fixed up and calibrated inside a few hours. Must have been a fabulous beast in its day, even now USB scope users see it and go off wanting a "proper" scope unless they have spent a fortune on something VERY high end. -- Best Regards, Chris Wilson.
|
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
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-----Original Message----- From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...] On Behalf Of Steve Sent: Sunday, December 30, 2012 4:14 PM To: hp_agilent_equipment@... 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> > 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@... <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> 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@...
<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>
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> > 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
|
Re: Oscilloscopes - analog but with digital capability?
Philips/Fluke PM339X Combiscope series are the true analog scope with proper digitiser, very easy to use and it performs well. The catch is it may not be very reliable. According to my experience, it's just running too hot inside possibly due to inadequate thermal design? Tim On 31/12/2012, at 9:40 AM, J. Forster wrote: Yes.
The Tek DPO, based on the 7704 (or possibly the 7704A) was the first AFAIK.
Then there was the magnificent 7854. IMO, this is the BEST lab 'scope
ever made. It is still my 'scope of choice.
The downfall of both of these units was the relatively slow A/D by modern
standards.
There were also some Transient Data Digitizers that used specialized
double ended CRTs, I think.
-John
=============
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that
were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this.
So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers?
Thanks for your time - sorry if that was a bit lengthy.
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
|
Steve, the one I'm getting appears to be start with 3114A for the serial number with STD (Standard) for options. I assume the serial number is above the bar code and under the model number. I've not received it yet, when I do I'll find out how many cals were done on it.
You figure it counts one cal number for each range. So is there 34 total cals to do the entire device ?
Thanks,
Jeff
toggle quoted message
Show quoted text
On 12/30/2012 3:13 PM, Steve wrote:
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>> 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@... <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>
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@...
<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>
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> > 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
|
Re: Oscilloscopes - analog but with digital capability?
Yes.
The Tek DPO, based on the 7704 (or possibly the 7704A) was the first AFAIK.
Then there was the magnificent 7854. IMO, this is the BEST lab 'scope
ever made. It is still my 'scope of choice.
The downfall of both of these units was the relatively slow A/D by modern
standards.
There were also some Transient Data Digitizers that used specialized
double ended CRTs, I think.
-John
=============
toggle quoted message
Show quoted text
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that
were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this.
So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers?
Thanks for your time - sorry if that was a bit lengthy.
|
Re: Oscilloscopes - analog but with digital capability?
Bryce,
Several Tektronix scopes work that way. The portable 2232, 2211, and several others have a STORE/NON-STORE switch that lets you look at the same signal in either mode. The Tek 7854 mainframe also can do this. In all the scopes I listed, the digitizer rate cannot support single-shot captures at full bandwidth.
--John Gord
toggle quoted message
Show quoted text
--- In hp_agilent_equipment@..., Bryce Schroeder <bryce.schroeder@...> wrote:
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this.
So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers?
Thanks for your time - sorry if that was a bit lengthy.
[Non-text portions of this message have been removed]
|
Re: HP 8970B firmware v2800+ wanted
I'm not sure how to get a ROM dump out of the unit, but mine is version
2844. Help me with capturing the data and I'll happily give you a copy.
73
Dave K2DH
toggle quoted message
Show quoted text
-----Original Message----- From: hp_agilent_equipment@... [mailto:hp_agilent_equipment@...] On Behalf Of f1gwr Sent: Sunday, December 30, 2012 4:54 PM To: hp_agilent_equipment@... Subject: [hp_agilent_equipment] HP 8970B firmware v2800+ wanted
In order to use a HP 8757A SNA as a display, the noise figure meter 8970B
requests version 2800 at least to enable special functions 47.x as described in Product Note 8970B/S-4. 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!
Almost two years ago I posted the above message, but till now did not get suitable answer. Maybe someone could read a recent ROM and post it? Please note K04BB's site only holds 2705 version of the firmware ROM, see: )_ROM_Images_and_Drivers/HP_8970B So I'm looking for 2800 release or later. Thanks for your help, Christian ------------------------------------ Yahoo! Groups Links
|
Haha, I guess not as it sold really quickly!
Peter
toggle quoted message
Show quoted text
On 12/30/2012 4:50 PM, Bruce Lane wrote:
At the risk of shameless self-promotion, I've placed a GPIB-to-USB adapter on the E-place for sale/auction. I hope I've chosen a reasonable price range.
If you want to have a look, it's item 150972490568.
Keep the peace(es).
-=-=-=-=-=-=-=-=-=-=-=-
Bruce Lane, Owner & Head Hardware Heavy,
Blue Feather Technologies --
kyrrin (at) bluefeathertech do/t c=o=m
"Quid Malmborg in Plano..."
--------------------------------------------------------------------------------
No virus found in this message.
Checked by AVG - www.avg.com <>
Version: 10.0.1430 / Virus Database: 2637/5497 - Release Date: 12/30/12
|
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@...> 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@...] On Behalf Of Jeff Machesky
Sent: Saturday, December 29, 2012 8:01 PM
To: hp_agilent_equipment@...
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@...
<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>
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> > 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]
|
Oscilloscopes - analog but with digital capability?
Did HP (or Tek, or anyone for that matter) make any oscilloscopes that were
basically analog scopes, but with the ability to digitize what is seen on
the display (at some lesser resolution than what you might be able to see
on the actual display, presumably)? As I understand it - which may
admittedly be incorrect - some of the older spectrum analyzers are sort of
like this.
So, this hypothetical oscilloscope type would basically have the analog
display "in parallel" with an ADC, such that you could look at the screen
and see the waveform displayed like an analog scope, or use the ADC to see
a digital approximation. (Presumably the digital stuff could also be used
to capture and store one-shot things like a regular digital oscilloscope.)
This would be opposed to a purely digital oscilloscope where the ADC and
memory is always between the signal and the display.
The reason for doing this, of course, would be that the analog display
would be "higher resolution" than the ability of the ADC, but the digital
stuff would enable automation and storage ability. This would stop being
important once digital was high-enough resolution to look more or less
indistinguishable to humans.
Did such "hybrid" oscilloscopes ever exist? If so, what are some model
numbers?
Thanks for your time - sorry if that was a bit lengthy.
|
HP 8970B firmware v2800+ wanted
In order to use a HP 8757A SNA as a display, the noise figure meter 8970B requests version 2800 at least to enable special functions 47.x as described in Product Note 8970B/S-4.
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!
Almost two years ago I posted the above message, but till now did not get suitable answer. Maybe someone could read a recent ROM and post it? Please note K04BB's site only holds 2705 version of the firmware ROM, see: )_ROM_Images_and_Drivers/HP_8970B So I'm looking for 2800 release or later. Thanks for your help, Christian
|
David Hess