Author Topic: DSO life expectancy  (Read 3900 times)

0 Members and 1 Guest are viewing this topic.

Offline Sylvi

  • Contributor
  • Posts: 44
  • Country: eg
DSO life expectancy
« on: September 13, 2018, 05:02:00 am »
Hi

This could be called "DSO for linear use"...

I work primarily with audio signals and analogue scopes have been the mainstay for decades. My first scope died after 30+ years and a new replacement died after just 18-months (one-year warranty plus some BONUS time - hehe)! The older one had through-hole components and leaded solder. I haven't opened up the new one yet, but I suspect it has a lot of surface-mounted parts and lead-free solder. In my experience, SM is not very good since it inherently has small solder connections, which might not be so bad were it not for the lead-free solder. The stuff is garbage!

I'm at the point where I figure I should get a digital scope but there are a few issues I wonder about.

First is reliability. The new scopes are made using new methods like SM and bad solder, so how long should one of these last? I can't afford to pay a few hundred dollars every year for a scope, let alone 500-1500 if I want better vertical resolution.  Digital hardware does not seem to last very long even without the issues of software and planned obsolescence.

Second is the latency between probing a signal and seeing a proper wave on the display. Digital audio equipment is notorious for this delay and it is a real problem in the recording studio. I'm used to the instant response of analogue scopes and I can see the latency issue driving me nuts.

Third is vertical resolution. 8-bits is really a joke. 256 increments compared to whatever the phosphor-dot density of an 8x8cm analogue screen? I see people in your threads here wonder why someone wants 12-bit or more resolution? Well, I do but I don't need that resolution out to 100MHz; rather, for the audio band plus a bit more - 100kHz would be fine but you do need reasonable resolution into MHz to find certain noise and transients.

Having a VGA output is a PLUS as it gives you an inexpensive way to have a much larger monitor than the tiny display. Most screen shots I see of DSO displays in action have all kinds of text and data around the perimeter and it would be nice for all of this AND the waves to be easily read even with my eyes.

I saw the Keysight G-version scopes can do Bode plots, which is pretty nice.But you have to spend 300$ over the base model to get that and still it is an 8-bit 50MHz scope.

I'm leaning towards an Owon scope since they seem to offer the best resolution at the lowest price.

Does anyone know how long these things should really last?
 

Offline metrologist

  • Super Contributor
  • ***
  • Posts: 1530
  • Country: 00
Re: DSO life expectancy
« Reply #1 on: September 13, 2018, 05:51:11 am »
They should have a three year warranty, maybe 5 for something expensive. Beyond that, use is luck of draw. Market is going to make it obsolete in 2 years probably as we progress.
 

Offline Sylvi

  • Contributor
  • Posts: 44
  • Country: eg
Re: DSO life expectancy
« Reply #2 on: September 13, 2018, 06:04:33 am »
Hi

Some warranties are shorter, but even with a listed warranty of three years say, most have to be shipped back to China especially if you buy through Aliexpress (I see better deals there than at Amazon).
You would hope the unit survives the warranty period but do you have to look at it as the manufacturer's claim of life expectancy? "It will last 3-years" then it dies a day later... My old scope probably only had a one-year warranty but it lasted 30-yrs - the second was 1-yr and lasted 1.5-yrs. I know it is the luck of the draw - you get a good one or you get a lemon.

I don't use Amazon since they falsely accused me of taking payment for reviews. When I asked about this, I only got form letters and then they withdrew all my reviews. So, I'll never buy anything there gain.
 

Offline nctnico

  • Super Contributor
  • ***
  • Posts: 15230
  • Country: nl
    • NCT Developments
Re: DSO life expectancy
« Reply #3 on: September 13, 2018, 06:18:48 am »
Third is vertical resolution. 8-bits is really a joke. 256 increments compared to whatever the phosphor-dot density of an 8x8cm analogue screen?
I doubt you get much more resolution from a CRT screen. There are noise and non-linearities in the vertical amplifiers.

The best warranty I'm aware of is offered by GW Instek. On (some of) their scopes the warranty ends 5 years after they stop producing the particular model.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline Gyro

  • Super Contributor
  • ***
  • Posts: 3617
  • Country: gb
Re: DSO life expectancy
« Reply #4 on: September 13, 2018, 06:24:50 am »
Third is vertical resolution. 8-bits is really a joke. 256 increments compared to whatever the phosphor-dot density of an 8x8cm analogue screen? I see people in your threads here wonder why someone wants 12-bit or more resolution? Well, I do but I don't need that resolution out to 100MHz; rather, for the audio band plus a bit more - 100kHz would be fine but you do need reasonable resolution into MHz to find certain noise and transients.

You'll normally find that it is the LCD resolution that actually limits the visible vertical display resolution rather than the ADC. Especially once you've got multiple channels displayed, on-screen options showing etc.
Chris

"Victor Meldrew, the Crimson Avenger!"
 

Offline DaJMasta

  • Frequent Contributor
  • **
  • Posts: 980
  • Country: us
    • medpants.com
Re: DSO life expectancy
« Reply #5 on: September 13, 2018, 06:32:35 am »
Plenty of people will complain about the quality of Chinese made inexpensive scopes, but I don't see any reason why you'd expect them to fail in the near term.  Perhaps the likelihood that they make it to a decade and are still going strong is not as good as from other makers or from eras when overengineering was more common (and the price reflected it), but I expect a good bit of my gear to last a decade with minimal maintenance, though my use case is far from 24/7/365.


If you're looking for stuff with a brand name, like the Owons you mention, there are reputable test equipment vendors that sell them as well which can offer their own warranty policy or information.  A company is only going to warranty what makes sense for the lifetime of the parts inside and what parts they want to have in storage, and with increasingly more integrated and less serviceable designs, it's harder to expect that distant support... so the warranty periods aren't that extensive, even if the parts have plenty of longevity.

In terms of failure modes outside of improper use, a modern scope is probably dependent on electrolytic capacitor lifetime, screen backlight lifetime (if a CCFL, at least), fan lifetime, or maybe rotary encoder lifetime.  Provided it's been designed well thermally, the reliability of construction is generally very good (and lead free solder is a VERY well understood process since it's used extensively in modern electronics, even if it's a pain to get right initially), and the lower power solid state parts used are probably more reliable than many of the solutions in equipment from the 80s or 90s... so there's really nothing making me expect that some of my newer gear won't be operational in 2025 or 2035.



As for your particular use case, there are some 12, 14, and higher bit options around - some of the newest scope designs are 10+ bits, and picoscope (PC based, but also big screen friendly) has been offering high resolution converters for quite some time.  You can also adjust your range switch and coupling to see very small details in most signals, so while the dynamic range of an 8 bit scope is quite limited, you can often still see very fine vertical detail.  There's also the option of getting audio specific DAC/ADC gear and using a software suite to get the displays you want - there are many options for getting bode plots on 24 bit audio signals using mid to high end sound cards and software.  There's also an increasing connectivity factor in some brands, where you can take a scope and plug a function gen into its USB port and have them coordinate automatically for bode plots and such.  Siglent has some options like that, but I think R&S and Keysight in particular have made a move towards this kind of integration, though you certainly spend for it.

If your tests aren't concerned with phase, you could also get your bode plot from a simple white noise generator and the FFT function on almost any modern scope.  You'd have plenty of sample rate for enhanced resolution mode for such a low frequency signal range (usually 1-2 more effective bits), and the newest generation of scopes can manage a 1Mpoint FFT for very fine frequency detail.

You shouldn't have delay issues using a scope.  If you use a USB one and you have some application where you need to see the signal in realtime, you may run into issues, but generally speaking, the waveform updates per second of a current generation scope are high enough that the delay from measurement to the screen is less than the several ms delay a lot of DSP hardware has, and I can't think of an application where syncing the visual with the input is all that important.  If you need to check alignment of very fast changes, there's always single shot mode, and if you're trying to coordinate a signal generator with what you see (for some reason), you can always just output a trigger signal from the sig gen to exactly align where the pulse was generated with what's being recorded on the scope.  Since a scope isn't really a tool for processing and replaying signals in realtime, it's for visualizing continuous ones and capturing fast transient ones, I don't think you'll ever run into the sort of 'round trip delay' issues you'd have with a DSP based audio recording and playback system.
« Last Edit: September 13, 2018, 06:36:39 am by DaJMasta »
 

Offline Sylvi

  • Contributor
  • Posts: 44
  • Country: eg
Re: DSO life expectancy
« Reply #6 on: September 14, 2018, 07:38:34 am »
Hi

That's a lot of good information.

I have no problem with buying stuff from China since their quality is whatever you are willing to pay for. The difference is their honour-system is a little different than in the west, but once you navigate that there are no issues. On the other hand, some of the US brands seem to charge a lot just because they are domestic and it props up their reputation to charge a lot. Keysight offers 3-yr warranty upgradable to 5-yr; maybe Techtronix does too. I had to look up Keysight's history to find out they were a spin-off of HP (Hewlett-Packard), so they are quite respectable, but...

There's a colloquial thought about linear versus digital/switching gear, sort of related to heart-beats in animals. Animals with fast heart rates seem to live shorter lives than animals with slow heart-beats; one theory being that everything has 2-billion beats and then it is done. If the same is true about 60Hz transformers, say, versus switch-mode supplies, then the linear item lasts forever compared to the SMPS. This is true with inverter welders compared to transformer-based ones, and when you look at the life cycle of computer-based stuff there seems to be a similarity. maybe it is just the "fitting the observation to match the theory" syndrome?  But it makes me a bit concerned about DSO life since most of the internals operates at high clock speeds.

If I could count on 10-yrs from the OWON with its 3-yr warranty that would be great! If it were that I could only count on 3-years for the 3-yr warranty it is less great but acceptable considering the accelerated development for these products, i.e. there might be 16-bit or 20-bit units out by then :)

Milliseconds are noticeable on the human scale, but maybe it does not matter for the scope application as you suggest.
 

Offline Sylvi

  • Contributor
  • Posts: 44
  • Country: eg
Re: DSO life expectancy
« Reply #7 on: September 14, 2018, 07:49:36 am »
The analogue scope that died six months after its warranty expired is a GW Instek. I have a function generator from them that is over 20-yrs old, so I expected better from the scope.

It turns out the company I bought the scope from does free repair estimates although it still costs me $80 to send it there and $80 to get it back. I'll get it fixed but still think I'll get a DSO, too
 

Offline bd139

  • Super Contributor
  • ***
  • Posts: 7049
  • Country: gb
Re: DSO life expectancy
« Reply #8 on: September 14, 2018, 08:04:17 am »
I've got a 1998 Tektronix TDS210 still going strong.

If you want something good for audio it might be worth looking at a Digilent Analog Discovery 2 instead of a normal DSO. That'll give you 100MSPS but 14 bits, AWG, plus network and spectrum analyser with THD, noise measurement capability https://store.digilentinc.com/analog-discovery-2-100msps-usb-oscilloscope-logic-analyzer-and-variable-power-supply/
 

Offline DaJMasta

  • Frequent Contributor
  • **
  • Posts: 980
  • Country: us
    • medpants.com
Re: DSO life expectancy
« Reply #9 on: September 14, 2018, 08:36:36 am »
Timing and speed are the strength of scopes, just as voltage precision is the strength of DMMs, so the advances in scope technology have been increased resolution (sample rate), increased storage, and increased processing to get that from the acquisition system into meaningful information to the user.  Personally, I haven't seen any correlation between operating frequency and expected lifespan.  There are some things that may superficially seem like that, but which end up being a different root cause than just frequency - a part being used on the edge of its thermal limits or at the edge of its drift parameters to maintain spec, an exotic material that's more sensitive to vibration, voltage fluctuations, etc. - it's basically never the signal frequency that causes damage, it's the tighter tolerances required for high speed devices requiring more sensitive devices, the heat associated with power requirements for operating fast, or other factors.  Especially in these mainstream range scopes, the designs are very well understood because their features are no longer leading edge, but that means that it's a much more manageable task to put together a working system because the performance tolerances available in the parts are much broader.  Some of this is eaten up by cost reduction, for sure, but a 200MHz frontend of today is going to fairly versatile and robust, whereas a 200MHz frontend 30 years ago was a specialty device made of exotic materials.  What used to be large, hot running ADCs made on ceramic hybrids are now off the shelf chips in a 10mm square BGA that can be passively cooled, even when operating faster, even though the package is significantly easier to design around and is more durable in the long term.  I guess my point is, just because it runs fast doesn't mean it's unreliable - we've gotten good at making fast stuff.

Any usage lag you run into will likely be limited by LCD screen refresh rate at any time scale small enough to fill the screen quickly (100ms per division still takes a second for an update if you're 10 divisions wide), but if you zoom in all the way with full sample rate on a modern inexpensive scope, you can easily see single digit nanosecond level alignment precision.  Enough so that if you had a 1m scope probe lead and a 2m scope probe lead, the timing difference between the two measuring the same source would be obvious.

Also worth mentioning that bit depth probably won't jump a staggering amount.  We've been stuck at 8 bits for a couple decades in the mainstream, and are only now seeing 10+ bit converters standard in regular scopes.  There's also sort of a limit on how quiet a signal can be made - even 24 bit audio converters only get 19 or 20 effective bits with a bunch of noise because of the limits of thermal noise and other sources - these very high resolution converters are also much slower than the sorts used in scopes, so it's unlikely to see audio resolution ADCs running at 1GS/s+ any time soon, let alone having them be built into mainstream scopes.  You can get better effective resolution out of averaging, oversampling, or other techniques, though, so you can get some very low noise signals from captures of a repetitive signal, even on an 8 bit converter.

Online Mechatrommer

  • Super Contributor
  • ***
  • Posts: 8248
  • Country: my
  • reassessing directives...
Re: DSO life expectancy
« Reply #10 on: September 14, 2018, 10:20:59 am »
First is reliability. The new scopes are made using new methods like SM and bad solder, so how long should one of these last? I can't afford to pay a few hundred dollars every year for a scope, let alone 500-1500 if I want better vertical resolution.
i cant tell about other digital scope such as Owon, Keysight, Hantek, Siglent etc, even my own 3 years old Rigol DS1054Z, but i can tell about my DS1052E that it still works for 9 years now, next year it will be its 10th year anniversary (geez time is too short), and its with my brother now.

Second is the latency between probing a signal and seeing a proper wave on the display. Digital audio equipment is notorious for this delay and it is a real problem in the recording studio. I'm used to the instant response of analogue scopes and I can see the latency issue driving me nuts.

Third is vertical resolution. 8-bits is really a joke. 256 increments compared to whatever the phosphor-dot density of an 8x8cm analogue screen? I see people in your threads here wonder why someone wants 12-bit or more resolution?
you clearly havent used a digital scope before. there is no such thing as latency or 256 steps joke. what you hear is hearsay or exaggeration from idealists, people want 12 bits scope because they are in multibillion dollar business building high end stuffs, so they want the best THD or FFT reading out of the scope, and they certainly can afford or easily justifying things like $9600  CS448 14 bits Isolated Oscilloscope and they will buy another one if they have to.

I saw the Keysight G-version scopes can do Bode plots, which is pretty nice.But you have to spend 300$ over the base model to get that and still it is an 8-bit 50MHz scope.
meet $5500 Bode 100 Vector Network Analyzer. if you really care about $300, you may get a $400 scope like DS1054Z and a $100 PC controllable function generator, learn programming and make the bode plot on a 30" PC monitor.
if something can select, how cant it be intelligent? if something is intelligent, how cant it exist?
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 8662
  • Country: 00
Re: DSO life expectancy
« Reply #11 on: September 14, 2018, 10:31:08 am »
Third is vertical resolution. 8-bits is really a joke.

Yes and no. DSOs do clever signal reconstruction and can average multiple waves together to improve those 8 bits. In reality, 8 bits is probably as good as your analogue 'scope when it comes to viewing a nice periodic wave on screen.

Of course they have a limited number of pixels on screen, you might be able to see those.

Does anyone know how long these things should really last?

There's not much data on that yet... because they simply aren't dying.
 

Offline Bassman59

  • Frequent Contributor
  • **
  • Posts: 974
  • Country: us
  • Yes, I do this for a living
Re: DSO life expectancy
« Reply #12 on: September 14, 2018, 10:44:33 am »
Hi

This could be called "DSO for linear use"...

I work primarily with audio signals and analogue scopes have been the mainstay for decades. My first scope died after 30+ years and a new replacement died after just 18-months (one-year warranty plus some BONUS time - hehe)! The older one had through-hole components and leaded solder. I haven't opened up the new one yet, but I suspect it has a lot of surface-mounted parts and lead-free solder. In my experience, SM is not very good since it inherently has small solder connections, which might not be so bad were it not for the lead-free solder. The stuff is garbage!

Except, no, SMT stuff built with lead-free solder is not garbage.

I have a Tek TDS2024 (original, not A, B or C) at home, bought it new in 1999 or whenever, and it's as good as new. No issues at all. I use it for audio work, and for microcontroller/digital work.

An HP1661E logic analyzer is on my bench, again all stuffed full of SMT, works like a champ, except that it's kinda big and anyway everything I do is FPGAs so there's no call for a traditional benchtop logic analyzer any more.
 

Online james_s

  • Super Contributor
  • ***
  • Posts: 6445
  • Country: us
Re: DSO life expectancy
« Reply #13 on: September 14, 2018, 02:01:16 pm »
I have several DSOs that are ~25 years old and they still work fine. I had to replace some power supply capacitors in a couple of them, attenuator relays in my TDS784 but that's about it. Overall they have been as reliable as my analog scopes.

8 bits of vertical resolution is plenty unless you are doing something really specialized. I doubt you'd be able to see the difference side by side between 8 bits and 12 bits in most cases.
 
The following users thanked this post: KWKolb

Offline joeqsmith

  • Super Contributor
  • ***
  • Posts: 4926
  • Country: us
Re: DSO life expectancy
« Reply #14 on: September 14, 2018, 02:32:57 pm »
I have several DSOs that are ~25 years old and they still work fine. I had to replace some power supply capacitors in a couple of them, attenuator relays in my TDS784 but that's about it. Overall they have been as reliable as my analog scopes.

8 bits of vertical resolution is plenty unless you are doing something really specialized. I doubt you'd be able to see the difference side by side between 8 bits and 12 bits in most cases.

My LeCroy 7200 is about that old.  It still runs fine.  I've had a few tant caps go bad in it but no other major problems. 

Looks like OP is asking about a specific scope.  I don't have anything that new. 

OP, if you are happy with an analog scope, why not just stay with that technology?   
How electrically robust is your meter?? http://www.youtube.com/channel/UCsK99WXk9VhcghnAauTBsbg
 

Offline tautech

  • Super Contributor
  • ***
  • Posts: 13022
  • Country: nz
  • NZ Siglent Distributor
    • Taupaki Technologies Ltd.
Re: DSO life expectancy
« Reply #15 on: September 14, 2018, 03:24:58 pm »
I have several DSOs that are ~25 years old and they still work fine. I had to replace some power supply capacitors in a couple of them, attenuator relays in my TDS784 but that's about it. Overall they have been as reliable as my analog scopes.

8 bits of vertical resolution is plenty unless you are doing something really specialized. I doubt you'd be able to see the difference side by side between 8 bits and 12 bits in most cases.

My LeCroy 7200 is about that old.  It still runs fine.  I've had a few tant caps go bad in it but no other major problems. 

Looks like OP is asking about a specific scope.  I don't have anything that new. 

OP, if you are happy with an analog scope, why not just stay with that technology?
That's certainly the simplest instead of needing to teach one eyed old dogs new tricks !  :box:
Avid Rabid Hobbyist
 
The following users thanked this post: egonotto

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 8662
  • Country: 00
Re: DSO life expectancy
« Reply #16 on: September 14, 2018, 10:59:37 pm »
Even low end DSOs need solid metal shielding and chassis inside. The first time you pick one up you'll be, like, "Damn, that feels solid". No twisting or creaking here.

eg. This $350 model:



Lead-free is horrible for use with soldering iron but they've got it figured out at an industrial level. It's all about temperature.

« Last Edit: September 14, 2018, 11:12:31 pm by Fungus »
 

Online rstofer

  • Super Contributor
  • ***
  • Posts: 4913
  • Country: us
Re: DSO life expectancy
« Reply #17 on: September 15, 2018, 12:37:09 am »

First is reliability. The new scopes are made using new methods like SM and bad solder, so how long should one of these last? I can't afford to pay a few hundred dollars every year for a scope, let alone 500-1500 if I want better vertical resolution.  Digital hardware does not seem to last very long even without the issues of software and planned obsolescence.


I'm pretty sure the PC you typed this on used SMT and lead-free solder.  Nobody seems concerned.

If you want real resolution and a really attractive price, consider the Analog Discovery 2.  There's a dual channel 30 MHz scope with 14 bit resolution.  More important, it will do Network Analysis directly using its internal signal generator (it has 2 arbitrary waveform generators capable of 12 MHz).

https://store.digilentinc.com/analog-discovery-2-100msps-usb-oscilloscope-logic-analyzer-and-variable-power-supply/

For folks interested in Audio, this seems like an attractive tool.  You would need the BNC adapter board in order to use scope probes.  For vacuum tube technology, you would need 100:1 probes but that would be the case for any other scope.

Don't overlook the advantage of a 27" display.
 
The following users thanked this post: Fungus

Offline Sylvi

  • Contributor
  • Posts: 44
  • Country: eg
Re: DSO life expectancy
« Reply #18 on: September 15, 2018, 03:47:32 am »
I really appreciate all the good info and experience you guys have!

I've only ever used analogue scopes, so I am used to seeing that smooth wave representation and instant response. Recording studio exposure to digital audio products and their time-lag pitfalls made me concerned about digital scope response inasmuch as being able to see things instantly when probing around a circuit. From what you say here, the sample rate and screen refresh times should be quick enough for that to be a nonissue.

A friend has a Fluke handheld scope that he raves about, but he often works on ladders and other barely accessible places sussing out audio installation issues. he is happy to see a signal and maybe if it is clipped or not. part from that, i don't think he is looking for deviations from sine that interest me. Otherwise, the display on his scope looks dreadful to me, and he has an anolgue scope on his work bench.

The USB scopes are interesting since modern computers are tiny and most packages like the Picoscope are built with proper BNCs in a box. That Digalent item seems like a toy in that regard. I'm not a programmer type and have some trepidation about navigating the software needed to use these and don't want using the thing to become a whole research project unto itself - my time is already amply filled - haha. Plus, scrolling through menus to make a basic measurement has no appeal at all - a unitised DSO seems like a better way to go for me.

I don't have a lot of money to spend on a scope right now - or on anything - and that makes trying to pick one out a bit harder, especially after having my new-last-year scope die already. If there was a good way to know the real life expectancy of these things it would be worth stretching the budget to get something a bit better than something merely functional. I guess I'm trying to skip the "starter-DSO" step and go directly to what would suit me for a while  :) Part of the problem of a tight budget.

My reference to the heart-beat analogy was not to say that the signal will damage the scope or wear it out; rather, the internal clock of the circuit is doing that on its own. Yes, I have computers here that are older. My 2012 Linux continues to lose functionality and because of its OS security level is denied access to more sites every month (the OS is not supported since a few years ago). Because of that, I am writing this on a Chrome desktop bought last year, but it too has already lost some functionality. Many of the problems with these things is the software but I do use them many hours a day - sometimes they are running all day. Surprisingly my offline computers are way more solid.

 

Offline DaJMasta

  • Frequent Contributor
  • **
  • Posts: 980
  • Country: us
    • medpants.com
Re: DSO life expectancy
« Reply #19 on: September 15, 2018, 04:28:42 am »
Not just on the front end, frequency specific aging does not happen in solid state devices.

Take the same chip from the same batch and run one at 500MHz and run the other at 100MHz - provided the 500MHz is still within spec and the core temperature and other environmental aspects are the same, they should last for the same time.  There's an analog with mechanical components, but solid state devices don't have the same base wear and tear from usage, so the comparison isn't really valid.  If you're looking at bleeding edge vs. bleeding edge, then maybe the lifetime is comparable with that of 30 years ago, but if you're looking at the same frequency then vs. now, the now will be more reliable and less expensive to implement, and though the comparison is a strange one, you can certainly get more speed for your life expectancy out of a modern component over an old one when they're designed for the same thing.  Semiconductor failures are almost always about heat - even ESD events are about localized spikes burning through tiny transistors.

Online Mechatrommer

  • Super Contributor
  • ***
  • Posts: 8248
  • Country: my
  • reassessing directives...
Re: DSO life expectancy
« Reply #20 on: September 15, 2018, 04:29:05 am »
I've only ever used analogue scopes, so I am used to seeing that smooth wave representation and instant response.
Recording studio exposure to digital audio products and their time-lag pitfalls made me concerned about digital scope response inasmuch as being able to see things instantly when probing around a circuit. From what you say here, the sample rate and screen refresh times should be quick enough for that to be a nonissue.
thats not your problem. your problem is you never used a digital scope before. dont worry, just get a Rigol DS1054Z and you'll never look back. everybody had their chance with analog scope as you do at some point in time. you may also get Siglent scope if bode plot is important to you, at a little bit pricey, and you need to buy their function generator as well, so combined may cost you near $1K i guess. Keysight? Rohde Scwarzh? more money you probably need to sell some part of your house for them leaving your house a big hole.

DSO is not a digital audio instrument, DSO (same as CRO) just take the signal and display it at sub micro or nano second delay, you will not be able to notice even it is ms delay. digital audio instrument need some heavy math real time post processing or some delay filter before you can hear the output, so they are different function you cannot compare them.

A friend has a Fluke handheld scope that he raves about, but he often works on ladders and other barely accessible places sussing out audio installation issues. he is happy to see a signal and maybe if it is clipped or not. part from that, i don't think he is looking for deviations from sine that interest me. Otherwise, the display on his scope looks dreadful to me, and he has an anolgue scope on his work bench.
Fluke famous because of safety feature, he doesnt want falling from ladder due to electric shock from short circuiting or sparking instrument. thats why probably they bought the Fluke. and yes, anything of that size and class will look terrible on monitor, even 5 digit price class i guess. there are cheaper version of handheld DSO and isolated input that looks nice on monitor, but they are not palm size so it will be awkward to bring up the ladder.

The USB scopes are interesting since modern computers are tiny and most packages like the Picoscope are built with proper BNCs in a box.
prepare for laggy display on Picoscope, the reviews in youtube show not that great refresh rate signal. get rigol or siglent "unitized" DSO you wont look back. you can google the review in youtube to see how fast they are at showing signals.

Yes, I have computers here that are older. My 2012 Linux continues to lose functionality and because of its OS security level is denied access to more sites every month (the OS is not supported since a few years ago). Because of that, I am writing this on a Chrome desktop bought last year, but it too has already lost some functionality. Many of the problems with these things is the software but I do use them many hours a day - sometimes they are running all day. Surprisingly my offline computers are way more solid.
format them and they will be as good as new, send to PC shop if you dont know how to do it yourself. the lagginess thats because modern OS are shit they want automatic internet update everytime. only few weeks or few times of use from newly installed, and they will be like shit slow, yes my Win10 machine is like that. i reformat my WinXP machine every 2-3 years and believe me WinXP is the lightest OS on the planet for the functionality and i still need to reformat it because performance (softwares) is deteriorating. my WinXP machine is 10 years old now after changing PSU twice, its not game grade machine is cheap to medium price hardwares.

btw... how is Al-Sisi? ;)
if something can select, how cant it be intelligent? if something is intelligent, how cant it exist?
 

Offline MrW0lf

  • Frequent Contributor
  • **
  • Posts: 861
  • Country: ee
    • lab!fyi
Re: DSO life expectancy
« Reply #21 on: September 15, 2018, 05:11:14 am »
The USB scopes are interesting since modern computers are tiny and most packages like the Picoscope are built with proper BNCs in a box.
prepare for laggy display on Picoscope, the reviews in youtube show not that great refresh rate signal. get rigol or siglent "unitized" DSO you wont look back. you can google the review in youtube to see how fast they are at showing signals.

Laggy is relative. Some stuff that may make it laggy is outright impossible on most scopes. I made 2408B laggy (2Hz) running 2x2Mpts FFT :D It is "analytical" scope if you wish, not so much "DPO". So if no need for high frequency and want to learn about digital signal processing there is 2204A which is less than 100EUR w/o probes and has full blown sw with many decoders etc. I started with 25MHz 2205 and its still going strong after 8 years. If want just DPO (digital phosphor) and keep it more along analog lines then look GW Instek GDS-1054B, which is very properly done thing, if too expensive for 50MHz look Siglent SDS1104X-E. Rigol is more for Arduino/digital tinkerers since it works best with digital type of signal (analog ones may get bit distorted at times...), but its cheap :P
« Last Edit: September 15, 2018, 06:02:33 am by MrW0lf »
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 8662
  • Country: 00
Re: DSO life expectancy
« Reply #22 on: September 15, 2018, 06:15:01 am »
Rigol is more for Arduino/digital tinkerers since it works best with digital type of signal (analog ones may get bit distorted at times...)

 :wtf:

What sort of analog signals will distort on a Rigol but no others?

 

Offline nctnico

  • Super Contributor
  • ***
  • Posts: 15230
  • Country: nl
    • NCT Developments
Re: DSO life expectancy
« Reply #23 on: September 15, 2018, 06:30:15 am »
Rigol is more for Arduino/digital tinkerers since it works best with digital type of signal (analog ones may get bit distorted at times...)
What sort of analog signals will distort on a Rigol but no others?
I guess MrW0lf is referring to the sin/x interpolation not being correct. This is a bit of a fail. BTW the GDS-1054B MrW0lf is referring to can be unlocked to 300MHz and have protocol decoding as well.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline MrW0lf

  • Frequent Contributor
  • **
  • Posts: 861
  • Country: ee
    • lab!fyi
Re: DSO life expectancy
« Reply #24 on: September 15, 2018, 06:30:48 am »
What sort of analog signals will distort on a Rigol but no others?

Response is clearly not Gaussian (analog scope like) over 50-60MHz with all channels on. Coming from analog scope Gaussian response would be much preferred. If interests lie below 50MHz or are limited to max 1-2 channels over 50MHz no prob.
« Last Edit: September 15, 2018, 06:32:22 am by MrW0lf »
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf