DSO Reliability

[J-D-H]

Having my Tektronics 465 fail recently was certainly depressing (great general purpose scope, IMO), but this does give me the opportunity to buy something new!  So I'm searching for a new dual trace scope with around 100 MHz BW, and settled on getting one of the ~many~ apparently Chinese made DSOs selling in the $400-450 range.

My main concern is reliability.  And so I'm overwhelmed by the number of extremely similar units which are available, many of which carrying company names which are new to me.  There are many made by Owon, Rigol, Siglent, etc., but I also found ones with more familiar names -- B&K Precision, Tektronics (although this one is more $), etc.  All these seem to have extremely similar front panel layouts -- does this imply that they are all made by the same manufacturer, in the same plant, etc?  Or is it more that form follows function?  Are they all built to the same level of reliability such that the company name becomes a non-factor?  I have done a fair bit of reading here, see many recommendations, but have yet to see any reviews concentrating on reliability.  Can anyone help?  And if I overlooked a good thread on this here, sorry, can someone please point it out?

John
Location: USA

[janengelbrecht]

If money is an subject go for Rigol. Good build quality, good precision , good reliability. More DSO for the dollar.
Rigol DS1102E : 100MHz Analog BW. (One could go for DS1052E and then make the 50Mhz->100MHz Hack ....but again...you could brick your scope then - and you will loose your warranty for sure!).

[nctnico]

IMHO looking for equipment which lasts 20 years is not a good idea. Better buy a new one every 5 to 10 years so you have the latest bells & whistles.

[nanofrog]

Within your budget, Rigol would be your best bet (good build quality and value for money).

In particular, the DS1054Z. Plenty of threads on it, and if you hack it, you can get 100MHz out of it as well as some other features (enable it's software options, including unlocking 24mpts of memory). Really is an amazing feature set for the money ($399 MSRP), even if you don't hack it.

And if you order from TEquipment.net, there's a code that will give you 6% off, so ~$375 (free shipping & a free gift tossed in for good measure). Can't be beaten right now for value.

PM sent.

[DanielS]

IMHO looking for equipment which lasts 20 years is not a good idea. Better buy a new one every 5 to 10 years so you have the latest bells & whistles.

What latest bells and whistles? There has been very little fundamentally new in DSOs in the past 15 years aside from companies like Rigol bringing feature sets previously only found on $5000+ scopes down to $500.

Just look at the number of people who still use their 20+ years old 20-250MHz analog scopes today - some people have even posted restoration videos where they have to reprogram the flash/NVRAM/EEPROM memory due to bit rot. It does not matter how old scopes and other laboratory instruments are: as long as they still work properly and are still appropriate for some everyday purposes, people will find uses for them.

For example: how much better will your scope from 2030 be at measuring ripple and noise on power supplies than today's DS1054Z or DS2012A? Likely not that much - scopes from 20+ years ago are still adequate for this today... some people even prefer analog scopes for this sort of stuff.

I much prefer having equipment that will last however long I have uses for it than being forced to replace it because it failed before I had any reason to buy something newer/better.

[nctnico]

IMHO looking for equipment which lasts 20 years is not a good idea. Better buy a new one every 5 to 10 years so you have the latest bells & whistles.

What latest bells and whistles? There has been very little fundamentally new in DSOs in the past 15 years aside from companies like Rigol bringing feature sets previously only found on $5000+ scopes down to $500.

Protocol decoding, longer memory, higher samplerates, digital channels, FFT, intensity grading, color TFT display, small form factor.

[Howardlong]

IMHO looking for equipment which lasts 20 years is not a good idea. Better buy a new one every 5 to 10 years so you have the latest bells & whistles.

What latest bells and whistles? There has been very little fundamentally new in DSOs in the past 15 years aside from companies like Rigol bringing feature sets previously only found on $5000+ scopes down to $500.

Protocol decoding, digital channels, FFT, intensity grading, color TFT display, small form factor.

...although boot time gets worse and never seems to improve.

Some of the oscilloscope fundamentals in the analogue domain don't improve quite as fast as the bells and whistles get bolted on. At the same time the systems we're debugging are getting faster and faster. I was debugging a 50MHz QSPI interface today, gave up with the $1000 brand new Rigol and went back to a 10 year old Agilent boat anchor and a Tek 2467B.

[Wuerstchenhund]

What latest bells and whistles? There has been very little fundamentally new in DSOs in the past 15 years

Well, I didn't know there were 100GHz scopes using technologies like DBI 15 years ago already (100GHz scopes only exist for roughly 10 years, and those were sampling scopes). Because I see something like that as quite a fundamental achievement.

This aside, there were lots of other advances within the last 15 years which make getting a modern scope worthwhile, for example higher sample rates, larger sample memories. Or much faster processing, which is the key to enabling even more advanced analysis functionality and higher trigger rates. Larger screens with higher resolutions, Decoding capabilities for a ton of buses and communication standards and so on.

aside from companies like Rigol bringing feature sets previously only found on $5000+ scopes down to $500.

No, not really. Rigol makes perfectly fine entry level scopes, but none of them (not even their DS6000 Series) has any remarkable features, in fact, aside from the large sample memory (which for the low sample rate of these scopes is dirt cheap these days), feature-wise they're pretty basic and in some areas (like FFT) are put to shame even by many scopes much older than 15 years.

Rigol was one of the first manufacturers to produce decent entry level scopes at prices lower than the established big brands. That's how they got their slice of the market, by delivering decent quality at low prices. If they had to fight by features they would have starved.

Just look at the number of people who still use their 20+ years old 20-250MHz analog scopes today - some people have even posted restoration videos where they have to reprogram the flash/NVRAM/EEPROM memory due to bit rot. It does not matter how old scopes and other laboratory instruments are: as long as they still work properly and are still appropriate for some everyday purposes, people will find uses for them.

Yes, but so what? Of course as long as these old scopes work (or can be restored to work) they can be used for the same tasks they have been used 20 years ago. But that doesn't mean that they're also adequate for more complex tasks, like debugging modern buses.

For example: how much better will your scope from 2030 be at measuring ripple and noise on power supplies than today's DS1054Z or DS2012A? Likely not that much - scopes from 20+ years ago are still adequate for this today... some people even prefer analog scopes for this sort of stuff.

Well, the thing is that probably only a very small minority of EEs use scopes for looking at basic stuff like ripple and noise of power supplies, and if the PSU in question is a complex switch mode PSU then a modern scope offers much better analysis capabilities than any analog scope from 20 years ago.

In 2030 we'll certainly have even more highly complex electronics and buses than today, and all of them will need debugging at some point. Your DS1054z or DS2012A, which even today are merely at the lower end of the performance scale, will be utterly useless by then.

I much prefer having equipment that will last however long I have uses for it than being forced to replace it because it failed before I had any reason to buy something newer/better.

That's fine for you. Unfortunately not everyone looks at PSU ripples, and more often than not I find that some of the new features of a new scope saves me so much time or makes my work so much easier that replacing it pays practically for itself, even when the old scope still works perfectly fine.

[DanielS]

What latest bells and whistles? There has been very little fundamentally new in DSOs in the past 15 years aside from companies like Rigol bringing feature sets previously only found on $5000+ scopes down to $500.

Protocol decoding, digital channels, FFT, intensity grading, color TFT display, small form factor.

I fail to see your point: LCD-based, portable oscilloscopes have been available for over 15 years and most features like serial decode and FFT have been available for even longer as extras even in the days of CRT-based DSOs. Nearly none of this is new; it has merely become smaller and cheaper. For someone who already own an optioned-up scope, there is very little reason to ditch it for a newer but otherwise equivalent instrument just for the heck of it.

[AndyC_772]

I've said the same thing. Every year they keep adding more memory, faster sample rates and reduced prices. I'll never spend more then a grand tops on a new DSO.

Even solely from an economic standpoint, if you have to buy three or four Rigols or other cheap Chinese DSO's you are still ahead versus buying one Agilent or TEK.

That's true, but you won't get the quality, ease of use or performance that comes with genuinely professional as opposed to budget equipment.

I've spent the last week bringing up, testing and debugging a new board with the aid of my Agilent MSOX3054A. It's true that I've not used all the bandwidth - 100 MHz would have been plenty - but I have been using all four analogue channels plus many of the digital channels all together, plus serial protocol decoding, advanced trigger modes, mathematical functions and segmented memory.

The screen has got a bit cluttered at times, but throughout the process, the scope has been consistently reliable, responsive, and an absolute pleasure to use. It's never crashed, become sluggish or unresponsive, or given me an obviously incorrect measurement. I use it without thinking, and that's high praise indeed.

I can't say the same for the last Rigol scope I used, which was a DS4054. By comparison it was sluggish and, unforgivably, had bugs in it which meant the serial decoding was next to useless. Occasionally it would lock up and crash.

What's worst of all is that the Rigol wasn't badly constructed, nor were there any obvious issues in how it acquired and displayed a signal. Its hardware was fine; all its problems were in the firmware, and many of them were so painfully obvious that it's heartbreaking that they made it out of the lab in the first place.

Spec for spec, the Agilent would have been twice the price - though buying it from the 'agilent used' Ebay store negated that particular disadvantage. Unless it has some kind of ticking time bomb inside, like an irreplaceable battery slowly going flat, I can see it occupying a space on my lab bench for quite some time to come.

[Wuerstchenhund]

I fail to see your point: LCD-based, portable oscilloscopes have been available for over 15 years and most features like serial decode and FFT have been available for even longer as extras even in the days of CRT-based DSOs.

I guess you've never really used FFT in a decent modern scope. Your old DSO clunker may have FFT, but for most scopes of that era will be limited to 100kpts or less (only undercut by modern Rigols which only use a few hundreds of points), and even then it will be painfully slow due to the slow processing.

And as to serial decode, good luck trying to decode modern common stuff like USB3 or 1Gbps Ethernet with your 15 year old scope. The world no longer only revolves around RS232.

[DanielS]

What latest bells and whistles? There has been very little fundamentally new in DSOs in the past 15 years

Well, I didn't know there were 100GHz scopes using technologies like DBI 15 years ago already (100GHz scopes only exist for roughly 10 years, and those were sampling scopes). Because I see something like that as quite a fundamental achievement.

I was writing that from the point of view of a private user - someone who has to spend his own money on buying the scope and other instruments. If you earn enough to afford spending over 1M$ on a new scope every 4-5 years to have the newest 100GHz scope on the market, knock yourself out. I suspect most people who own their own equipment are more like Dave himself: if it ain't broke, don't fix it - keep using the things until they are either no longer fit for purpose or beyond economic repair.

For industrial/R&D stuff, you use what you need to use (or whatever you can convince your bosses to get you) and there is not much room for discussion there.

[DanielS]

And as to serial decode, good luck trying to decode modern common stuff like USB3 or 1Gbps Ethernet with your 15 year old scope. The world no longer only revolves around RS232.

How many people are going to buy oscilloscopes capable of that for personal use? Next to none.

When the employer is paying for hardware, it becomes much easier say: "I do not care if my 100k$ scope blows up after four years, I'm not the one paying for it anyway."

[janengelbrecht]

if we are talking hobby use...well what are you going to work with ? RF? 800MHz ARM microcontroller ? FPGA ? or small AVR at 16MHz and LF...in the last scenario a 50MHz DSO is all you need ( Rigol ) If i need spectrum analyzing / FFT i export my data to a computer and makes the calculations there so my Rigol DS1052E is all i need

[Wuerstchenhund]

I was writing that from the point of view of a private user - someone who has to spend his own money on buying the scope and other instruments.

Well, you didn't say that your POV is limited to private users. In fact, you suggested there was no noticeable development in scopes in the last 15 years which, as I pointed out, simply isn't true.

And even if we're talking about hobbyists only I do have to disagree with your idea that a new(er) scope wouldn't offer any advantage over a 15+ year old one.

And as to serial decode, good luck trying to decode modern common stuff like USB3 or 1Gbps Ethernet with your 15 year old scope. The world no longer only revolves around RS232.

How many people are going to buy oscilloscopes capable of that for personal use? Next to none.

How do you know? For example, I know quite a few poeple who tinker with micro controllers and FPGAs for various hobby projects, and they need to look at stuff like USB or Ethernet. Not all can afford new scopes of course so some buy second hand high end scopes which are maybe 5 to 7 years old, which can be had pretty cheap these days and which offer the necessary capabilities. A few also bit the bullet and bought a semi-new scope (ex demo).

When the employer is paying for hardware, it becomes much easier say: "I do not care if my 100k$ scope blows up after four years, I'm not the one paying for it anyway."

Not everyone who uses a scope to earn money is employed or has a large budget. In fact, even in larger companies large budgets which allow to splash out money just for the sake of it are certainly in the minority.

[DanielS]

I was writing that from the point of view of a private user - someone who has to spend his own money on buying the scope and other instruments.

Well, you didn't say that your POV is limited to private users. In fact, you suggested there was no noticeable development in scopes in the last 15 years which, as I pointed out, simply isn't true.

I was merely staying on-topic: I should not have had to point this out since OP is looking for a replacement for his busted Tek 465 analog scope. Being up-to-date with the latest whizbang features is clearly nowhere near the top of OP's priority list.

[nctnico]

Perhaps not but I have seen it many times: at some point people buy the most expensive oscilloscope they can afford and think it is the best oscilloscope they will ever own for the next 30 years. I upgrade my oscilloscopes every few years.

[particleman]

I think it totally depends on what you do with your scope. I repair vintage audio gear upgrading my scope every few years would make zero sense for what I do.  I would say buy a scope that meets your needs.

[TunerSandwich]

IMHO looking for equipment which lasts 20 years is not a good idea. Better buy a new one every 5 to 10 years so you have the latest bells & whistles.

What latest bells and whistles? There has been very little fundamentally new in DSOs in the past 15 years aside from companies like Rigol bringing feature sets previously only found on $5000+ scopes down to $500.

 

[janengelbrecht]

I think it totally depends on what you do with your scope. I repair vintage audio gear upgrading my scope every few years would make zero sense for what I do.  I would say buy a scope that meets your needs.

Cant see any need to go further Answer above says it all I think

[tautech]

Interesting the OP has asked about reliability and this has barely been addressed.
As all modern scopes use at least 1 SMPS within, this is indeed a valid question.
This is generally the highest stressed part/s of any design.
As manufacturers compete on price component quality (and other features) suffers.
To have a SMPS fulltime online(powered) might be appropriate for a DSO that is in daily use but IMO the likely first point of failure over an extended period of time.
Several manufacturers have a mechanical type mains switch that removes any SMPS from fulltime mains connection, which IMO is preferable for hobbiest/intermittant use.

Mostly this type can be identified by the switch placement on top of the DSO as the force to activate the switch would displace the DSO if placed on the front panel.

Any of the recent DSO's of the more popular brands will be opening a new world for the OP with even the basic features now incorporated in DSO's.
As this is his first step into this new world my advice is to find a seller that can offer support and purchase a 100 MHz 1 Gsa/s 2 Mpts DSO.
Learn and explore the new capabilities available and get on with fixing your 465.
Depending on you future requirements, you may need little else.

[David Hess]

Perhaps not but I have seen it many times: at some point people buy the most expensive oscilloscope they can afford and think it is the best oscilloscope they will ever own for the next 30 years. I upgrade my oscilloscopes every few years.

I upgrade as well but by buying older oscilloscopes which provide functions and performance that I cannot afford in a new oscilloscopes.

The noise issue is interesting because I make that sort of quantitative measurement all the time on my analog oscilloscopes using the tangental method.  Some expensive DSOs explicitly support noise measurements in one way or another but a windowed RMS measurement on an inexpensive DSO should work but not all DSOs support measurement windows (I did not find this function in the Rigol user manuals anyway) and DSO automatic RMS measurements inexplicably do not always work when measuring noise.

As far as FFTs, old DSOs are slow and used a limited number of sample points but at least some of them displayed the phase information instead of throwing it out.  I still want an old TDS500 or TDS700 series oscilloscope just to get that.

Aliasing on fast edges bothers me.  Analog oscilloscopes and DSOs with equivalent time sampling product consistent results.  DSOs with digital triggering need to use averaging and even then, they seem to have more problems with this which is apparently solved with marketing.

[DanielS]

To have a SMPS fulltime online(powered) might be appropriate for a DSO that is in daily use but IMO the likely first point of failure over an extended period of time.

No doubt about the power supplies, especially their output caps, being the most common failure point in most modern devices. Then again, few devices have anywhere as many output caps per rail and per watt as the 1000Z's power supply has, and the scope only draws about 30W/ 50VA  including conversion losses so those output caps should have hardly any stress on them at all. I would be surprised if they started becoming problematic sooner than 7-10 years. On the plus side, they are relatively easy to inspect and replace if necessary; just need to remember to start checking up on them maybe once a year, just in case.

For people who really want to keep their devices around for a long time, bit-rot might become a significant concern after the 12-15 years mark.

[nctnico]

IMHO it is hard to predict what fails first. Tektronix was plagued by bad electrolytic capacitors in the late 80's and early 90's.
On a TFT screen the backlight is the weak point. In general weak points are components which get hot.

[G0HZU]

Having my Tektronics 465 fail recently was certainly depressing (great general purpose scope, IMO), but this does give me the opportunity to buy something new!  So I'm searching for a new dual trace scope with around 100 MHz BW, and settled on getting one of the ~many~ apparently Chinese made DSOs selling in the $400-450 range.

If you were happy with the 465 then why not fix it or buy another?

Then look at evaluating a new DSO in slow time. I can pretty much guarantee you will find things about a modern DSO you will not like and things you will like (in comparison to the old 465).

The best combo is to have the 465 and a DSO to get the best of both worlds. Another reason to fix the 465!

The other thing to be wary of is fan noise. Quite a few DSOs can be very noisy and this can be very distracting if you are used to working in a fairly quiet environment at home.