Keysight DSOX1202A specs (2020) are less impressive than HP54645D specs (2000) - Page 1
Forum section: electronics / testgear

author: pascal_sweden
author_rank: Super Contributor
timestamp: June 30, 2020, 03:01:33 pm
content: After 20 years of innovation, the bandwidth and the memory depth is the same, and the waveform update rate has not been significantly improved.Only the sample rate has been improved, but that's about it!In fact, the Logic Analyzer functionality has been removed. Really?Check for yourself in the attached documents!Note that the HP54645D oscilloscope was a real work horse, and could perform all this magic using an 8 MHz Motorola 68000 microprocessor, a 25 MHz Texas Instruments TMS320C50 DSP processor, and the MegaZoom architecture.How is it possible that HP could make such a powerful oscilloscope back then with such a modest microprocessor and DSP processor?There is a much more powerful CPU in today's Keysight DSOX1202A, still it does not perform any better whatsoever compared to its 20 years older brother!Why does HP make an oscilloscope in 2020, that is very similar but in fact worse than an oscilloscope from 20 years ago?Is this done on purpose to misguide and disrespect the intelligence of oscilloscope enthusiasts? Somehow I consider this a crime!

author: gslick
author_rank: Frequent Contributor
timestamp: June 30, 2020, 03:36:44 pm
content: Quote from: pascal_sweden on June 30, 2020, 03:01:33 pmSeriously? If the product sells why do you care? Buy a different product with a price / performance / feature set that appeals to you.

author: jxjbsd
author_rank: Regular Contributor
timestamp: June 30, 2020, 03:39:08 pm
content: This is similar to the I7 3960X released 8 years ago, far exceeding the current i3 9100F.

author: pascal_sweden
author_rank: Super Contributor
timestamp: June 30, 2020, 03:49:29 pm
content: You must have missed my comment about the Motorola 68000 microprocessor!

author: jxjbsd
author_rank: Regular Contributor
timestamp: June 30, 2020, 03:58:03 pm
content: Strictly speaking，DSOX1202A is DPO，And 54645D is just DSO, DPO requires much more computing power than DSO.DSOX1202A is just a cheap entry-level DSO.

author: pascal_sweden
author_rank: Super Contributor
timestamp: June 30, 2020, 05:17:47 pm
content: Intensity grading does not require extra memory:The sample memory does not store intensity levels.Intensity grading requires multiple samples and a display memory that can be overridden:The intensity levels are built up in the display memory by capturing multiple samples over time.The grayscale image is created using special processing logic and a custom graphics processor to overlay data in the display memory.It should be technically feasible to implement intensity grading on the HP54645D as well.Even with an 8 MHz Motorola 68000 microprocessor and a 25 MHz Texas Instruments TMS320C50 DSP processor!

author: Sighound36
author_rank: Frequent Contributor
timestamp: June 30, 2020, 05:22:46 pm
content: PascalYou must be seriously board or have far too much time on your hands, your threads of late have been somewhat skewedshall we say!

author: pascal_sweden
author_rank: Super Contributor
timestamp: June 30, 2020, 05:27:24 pm
content: I do have a point in my original posting, if you are honest.At this moment, it is however unclear if the vendor does it because of professional ignorance or pursuit of profit!

author: stafil
author_rank: Regular Contributor
timestamp: June 30, 2020, 06:01:00 pm
content: It's market segmentation. Every market leader does it. Look at Canon and their cameras. Not sure why 1. it comes as surprise, 2. some people feel entitled to have a saying in that.The best you can do, is vote with your wallet and not buy their products.Having said that, DSOX1202A does fewer things in comparison to competition, but damn does it do them properly

author: tom66
author_rank: Super Contributor
timestamp: June 30, 2020, 08:38:03 pm
content: Keysight and Tektronix have been behind for a while. That's why the Chinese DSO manufacturers have been taking their lunch.

author: pascal_sweden
author_rank: Super Contributor
timestamp: June 30, 2020, 09:26:42 pm
content: The HP54645D seems very responsive for a Motorola 68000 microprocessor as the central processing unit!

author: jxjbsd
author_rank: Regular Contributor
timestamp: July 01, 2020, 01:03:37 am
content: It feels like you prefer 68000 to 54645.68000 is indeed a suitable controller. This RISC CPU is better at doing controllers. The data processing engine is DSP TMS320C50. This is a suitable configuration. It is unclear whether the later DSO used a separate DSP IC?I prefer the DSO of series 54622 and 54642.A few years ago, when choosing 54642 or the defective 6052A, I chose the defective 6052A and then fixed it.Later, when I saw the post of hacker 6052A in EEV, DSO6052A became MSO6052A. Enable all options

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 01, 2020, 02:06:26 pm
content: More details about the Variable Intensity Algorithm in the HP54645D oscilloscope:See attached file!

author: jxjbsd
author_rank: Regular Contributor
timestamp: July 01, 2020, 02:51:59 pm
content: If the brightness of an analog oscilloscope can be approximated by a 16-bit binary floating point number, then the brightness of most DPOs can be expressed by an 8-bit binary number, DSO uses 1 digit to represent 0,1, and HP54645D can use 1 bit Ternary numbers to represent 0, 0.5, 1.I hope my understanding is correct.

author: martinot
author_rank: Regular Contributor
timestamp: July 02, 2020, 11:27:42 am
content: Quote from: gslick on June 30, 2020, 03:36:44 pmPascal Swede seems to waste his time trolling and dissing Keysight scopes day and night.Quite pathetic.He probably got bored in dissing other computers than Commodore...

author: nctnico
author_rank: Super Contributor
timestamp: July 02, 2020, 11:32:28 am
content: Quote from: Sighound36 on June 30, 2020, 05:22:46 pmYou forgot smoking the 'the bad stuff' but for the rest I agree.

author: martinot
author_rank: Regular Contributor
timestamp: July 02, 2020, 11:34:22 am
content: Quote from: tom66 on June 30, 2020, 08:38:03 pmI think that is highly debatable. It's like saying that German premium car manufacturers are "behind" Asian car makers.I personally gladly pay more for a new Mercedes-Benz, even if could get from A to B in the same speed by going in a cheap Korean or Chinese car.But that said; at least you compare with cars and scopes available on the market today.Comparing todays products with what was sold 20 years ago is just trolling...

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 02, 2020, 02:33:33 pm
content: You guys (or should I write girls) seem not to get the point!A modern oscilloscope based on a beefy microprocessor should perform way better than a 20 year old oscilloscope based on a modest 68000 microprocessor.In Keysight's case it doesn't! They even decided to drop the Logic Analyzer.And still you don't see any issues?Is it because of Jante's Law that you have to obey?https://en.wikipedia.org/wiki/Law_of_JanteThe Swedish communist with only 10 posts in total on this forum. That's what I call pathetic!

author: Kean
author_rank: Unknown
timestamp: July 02, 2020, 04:12:20 pm
content: No, you don't seem to get the point. A modern scope has significantly more functionality.Sure there will be some bloat in the modern software, but if you think you can compare the architecure of two scopes designed 20 years apart then you're delusional.

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 02, 2020, 05:32:07 pm
content: The bandwidth is the same as 20 years ago.The sample memory is the same as 20 years ago.The MegaZoom architecture is the same as 20 years ago.The only improvement is the increased sample rate and support for protocol decoding.But where is the logic analyzer?If one could properly implement a 16 channel logic analyzer on an oscilloscope with a Motorola 68000 microprocessor, why should one drop this after 20 years on an oscilloscope with a much more powerful microprocessor?Regarding protocol decoding: I believe there were optional modules for protocol decoding already 20 years ago, that worked perfectly on the oscilloscope with a Motorola 68000 microprocessor.You are right that the underlying microprocessor architecture is different:The HP54645D architecture based on a Motorola 68000 microprocessor was super efficient!The Keysight DSOX1202A architecture based on a much more powerful microprocessor is inefficient!The oscilloscope from 20 years ago was designed by engineers that were much smarter than today's engineers!

author: stafil
author_rank: Regular Contributor
timestamp: July 02, 2020, 06:02:23 pm
content: What was the launch price of HP54645D? Do you know?

author: 1Ghz
author_rank: Unknown
timestamp: July 02, 2020, 06:20:56 pm
content: FYI, in September, 1996, the US list price was USD 4,995.Source: NASA Tech Briefs, September 1996. Volume 20, No. 9, Page 31https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100028920.pdfUSD 4,995 in 1996 is worth USD 8,162.45 today.Source:https://www.in2013dollars.com/us/inflation/1996?amount=4995

author: Kean
author_rank: Unknown
timestamp: July 02, 2020, 06:28:42 pm
content: Quote from: pascal_sweden on July 02, 2020, 05:32:07 pmI'm no scope expert, but I know those specs have almost nothing to do with the microcontroller. The 68000 was there to handle the monochrome user interface and a few simple optional communications busses.In comparison the DSOX1202A needs to support a colour UI, complex menuing, built in help, multiple language support, protocol decoders, a bunch of automated measurements, Wavegen & FRA (on G models), and standard connectivity via LAN & USB. It also has 10 times the sample rate, but that is not really related to CPU processing.Anyway, feel free to keep using the 20 year old scope. I don't use any HPAK scopes, but the 54645D is still a pretty nice one if it has the features you need. I'm generally much happier when using my 1 year old RTB2004 vs my 12 year old Tek TDS2024B or myslightly older7514Quote from: stafil on July 02, 2020, 06:02:23 pmI did a bit of digging but couldn't find an original price. A bunch of info on the scope implementation in HP Journal April 1997.Apparently Mike Harrison (mikeselectricstuff) was thinking about buying one in late 1997:http://sxlist.com/techref/postbot.asp?by=thread&id=%5Bot%5D+hp54546D+MSO+%2D+opinions+please%21&w=body&tgt=top

author: Kean
author_rank: Unknown
timestamp: July 02, 2020, 06:37:32 pm
content: Quote from: 1Ghz on July 02, 2020, 06:20:56 pmOK, so that works out to about USD 8,000 today usinghttps://www.usinflationcalculator.com/More than 10 times today's price of the DSOX1202A at USD 750

author: 2N3055
author_rank: Super Contributor
timestamp: July 02, 2020, 07:49:17 pm
content: Quote from: pascal_sweden on July 02, 2020, 05:32:07 pm1. wrong new one has 200MHz max bandwidth, and that is not for repetitive signals only but realtime. Huge difference.2. Wrong, new one has 2Mpoint memory. But lame compared to competition, I agree.3. Wrong. Old one had original Megazoom I, new one is Megazoom IVQuote from: pascal_sweden on July 02, 2020, 05:32:07 pmThe whole idea is that has 10x faster sampling and protocol decoding. Logic analyser is used much less nowadays, serial protocols decodings are more important.To top off all that, like others said nicely, you should be comparing HP54645D with new Keysight MSOX3034T for instance to keep comparing price for price...Don't get me wrong, it is impressive what those brilliant engineers were able to accomplish back then.But let's not confuse apples and oranges..

author: CDaniel
author_rank: Frequent Contributor
timestamp: July 02, 2020, 08:02:06 pm
content: This topic is stupid , what changed fundamentally in all the cars from 20 years ago ? Fly or have top speed of 350Km/h ?Of course the new scope has more measurements , FFT , math and many more small improvements . If you want 1GHz bandwidth buy an expensive one . Some options will remain options regardless of time .

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 02, 2020, 08:12:27 pm
content: I was comparing the base model of the Keysight DSOX1202A with external trigger, without the options for which you have to pay extra!This means a bandwidth of 100 MHz and a sample memory of 1 MB, exactly the same as 20 years ago.Are you sure that the MegaZoom architecture in the Keysight DSOX1202A is MegaZoom IV?What is the waveform update rate for the Keysight DSOX1202A?I read that the HP54645D oscilloscope already had an update rate of 3 Million vectors per second.If we can calculate the amount of vectors per second for the Keysight DSOX1202A, then we can compare them relatively.Maybe the difference is not that big after all! And then we have the proof that the 20 years old architecture based on the Motorola 68000 was superior!This would finally clarify the reason for my posting:The base model of an oscilloscope manufacturer should be better in every single aspect than an oscilloscope which is 20 years old!Anyhow, I give up now! There are too many people with flaps and without common sense here!Quote from: 2N3055 on July 02, 2020, 07:49:17 pm

author: gslick
author_rank: Frequent Contributor
timestamp: July 02, 2020, 08:20:38 pm
content: Quote from: pascal_sweden on July 02, 2020, 08:12:27 pmGood.Quote from: pascal_sweden on July 02, 2020, 08:12:27 pmI only count one...

author: TK
author_rank: Super Contributor
timestamp: July 02, 2020, 08:26:19 pm
content: Quote from: pascal_sweden on July 02, 2020, 08:12:27 pmSample memory is now 2Mpts, refresh rate is 200,000wfm/s. Not even the current 3000T has 3Mwfm/s, it means something different. On the modern KS, you can measure the wfm/s from the trigger output BNC.

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 02, 2020, 08:37:46 pm
content: Quote from: pascal_sweden on July 02, 2020, 05:32:07 pmMaybe the difference is not that big after all! And then we have the proof that the 20 years old architecture based on the Motorola 68000 was superior!This would finally clarify the reason for my posting:The base model of an oscilloscope manufacturer should be better in every single aspect than an oscilloscope which is 20 years old!It should have a much higher bandwidth after 20 years!Why isn't 350 MHz or 500 MHz standard today?It should have a much deeper sample memory after 20 years!Why isn't 200 MSamples standard today?It should have a much higher waveform update rate after 20 years!Why isn't 1 Million Waveforms per second standard today?It should still have a logic analyzer after 20 years!Why would a logic analyzer not be useful anymore today? Every user will need this some day!

author: tv84
author_rank: Super Contributor
timestamp: July 02, 2020, 08:41:22 pm
content: Quote from: pascal_sweden on July 02, 2020, 08:12:27 pmPascal,I still haven't figured it out!Your OP was interrogative. As such, why don't you accept that others (with plenty of "common sense") have different opinions from the information/questions you posted?If you aren't willing to accept their opinions why do you launch these type of open threads in the 1st place? Not everyone is willing to be evangelized!Now, excuse me, I'm going to the aviation forum to demand the same thing! I want to fly in a commercial SR-71, NOW! (oops, it's not 20 years, it's 60 years old...)

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 02, 2020, 08:49:02 pm
content: I was hoping that more people here on this forum take my side, and agree that the vendor does it because of professional ignorance or pursuit of profit!Quote from: pascal_sweden on June 30, 2020, 03:01:33 pm

author: 2N3055
author_rank: Super Contributor
timestamp: July 02, 2020, 09:08:15 pm
content: Pascal,you seem not to have enough knowledge on topic, to discuss this. Sorry.For instance, old one claims 3 mega VECTORS. That means it was able to paint 3 milions interpolation segments on a screen. On most timebases that was same as 3 milion POINTS per second. So at 500 horizontal points that sums up to 6000 triggers per second. Max.Not 10000, not 100000, nor 1 milion screens per second. So you're wrong. And as I said 3000T series today has 1M triggers per second. Or in old parlance, that would be 600 milions of pixels/vectors. That is factor 200X better.Analog bandwidth of input amplifiers is equally complicated and expensive as it was. Digital revolution don't mean squat there.Short memory I give you. Ask Keysight why Rigol and Siglent can do it.I have MSOX3000T and Zeroplus LAP-C, and Digital discovery, and Picoscope MSO. I don't use many channels very often. I don't repair old computers so much, nowadays most of the stuff is serial. PC based decoding is better for lot of decoding. MSO is nice but not necessary. 4ch scope does most of the job.Of course manufacturers do it for profit. What else? And as long as they sell well, it means they're doing good job.Industry doesn't require better. And Keysight and other A brands don't care much about cheap segment. Or your opinion as hobbyist.

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 02, 2020, 10:19:10 pm
content: I will stick with the HP54645D oscilloscope powered by the Motorola 68000.For my next purchase I will definitely go for a Rigol or a Siglent oscilloscope.These Chinese companies are very talented and build products for the masses not the classes!In that respect they follow the Commodore philosophy! See attachment!

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 02, 2020, 10:34:54 pm
content: If you want to learn more about the system architecture in the HP54645D, check the April 1997 issue of the HP Journal.https://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1997-04.pdf

author: TK
author_rank: Super Contributor
timestamp: July 02, 2020, 11:43:02 pm
content: I like the 54622D. I think it has a 68030. Display is awesome

author: tv84
author_rank: Super Contributor
timestamp: July 03, 2020, 08:56:11 am
content: Quote from: pascal_sweden on July 02, 2020, 10:19:10 pmVery well said!

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 04, 2020, 01:59:34 pm
content: HP54645D advertisement in the Nasa Tech Briefs Sept 1996 issue.

author: pascal_sweden
author_rank: Super Contributor
timestamp: July 04, 2020, 02:06:57 pm
content: I am looking for the product presentation CD ROM on the HP54645D.Does anyone have this CD ROM?