EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: k4rlhp on June 15, 2017, 08:34:14 pm
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Here's the issue.
Bought Keysight DSO-X 3000T series with appbndl enabled ca. 2 years ago. Wanted a quality instrument of all things.
In the spirits of the proverb "feel the pain when you pay for it or feel the pain every time using it" kind of thing.
Maybe 3 months into use, bam-hazam, scope hard-freezez during boot and wont just progress further.
Of course, this happens during such time where the scope is needed the most.
Issue was intermittent, so it took time before I finally sent it to Keysight for repairs.
The scope was repaired, calibrated and sent back. okay.
Now I have new issue. the thing won't trigger. Waveforms just run across the screen like crazy. Channel wont matter. trigger settings wont matter.
It looks like it needs significant warm-up time (15..20 minutes). Then, after this warmup or whatever, it starts triggering gradually over ca. 10s period. more and more until triggering becomes stable and issue goes away for another week or more.
Again intermittent. Possibly related to temperature (yeah,yeah, cold joint or smth, but that's for repairs section)
Naturally, I will send it back to Keyshight (oops) again but given the issue is intermittent, who knows what keysight will or wont do...
So, I'm pretty much fed up with that.
As the saying goes, First time, shame on you. The second time, shame on me ;(
Are Tek scopes any better than that?
Thinking of a ~350MHz 4channel 4000series 3 domains scope. Shariar has given thumbs up and that looks like good stuff.
Has anyone had similar quality issues with Tek scopes?
Should I expect any better from Tek?
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FWIW, and I'm certainly biased, I have been using my MDO4000C nearly everyday for the last 2.5 years, never any trouble at all.
I would say that I'm surprised that you're seeing trouble like that with a KeySight instrument. I wouldn't have expected that, just as I wouldn't expect this kind of trouble with a Tek scope.
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Wow, I'm sorry to hear you've had such a rough time. I'm sure it doesn't make you feel any better, but to have two failures like this is extremely unusual for our scopes. If you need a loaner unit to hold you over while yours is in the shop or have any trouble with the repair folks let me know.
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I have the EDUX1002G and I am opening it all the time, using a heat gun to remove components, solder new components, exchange components... and it boots and works everytime I need. Maybe you have case of cold solder on one of the large ICs with BGA...
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I have the EDUX1002G and I am opening it all the time, using a heat gun to remove components /...
Hi. I haven't opened the unit and will not do it until the warranty lasts.
When it's over in about 1y then I might consider that.
I want to have it in spec too, so just heating random parts probably won't end so well for that.
I fixed one of my older Keithley 2015 6 1/2 digit meters and it's not so easy to do a pristine job. Later you will wonder why it drifts so much.
Of course, a 6 1/2 meter is quite easy to screw up in that sense.
Took effort and planning to get good result.
So I'll reserve that option for later.
Regards,
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I have several 2000x 3000x 6000x and 7000 series Keysight scopes in my lab and with customers / clients and never had any issues at all.
Yours must be a very unlucky instrument.
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Personally, I've seen tons of past-warranty Tek and HP/Agilent/Keysight scopes and test equipment floating around labs and staying stable as the workhorse you expect them to be.
I've never seen one defective, except on eBay listings.
I think the quality of the design is top notch, from both companies. But ultimately, everybody uses the same assembly processes, and they do have their failures (like the suggested cold BGA leg).
The main difference between Tek/Keysight and the newcomers to the market is how they are expected to treat their clientele.
You paid a mid-level scope with a huge markup on the sticker price. You paid for quality, and Keysight did not deliver (on this particular unit). Now, you need to let them know this is not acceptable.
After one unsuccessful attempt at refurbishing, I would tend to require a brand new replacement, and an apology, and maybe a rebate on your next purchase.
I still think you're just being unlucky, but that is not OK from either Tek or Keisight
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With so many different small series products, there are always good and not so good products. So there are a few scopes from both brands that did have issues and might fail more often, while others are still working rock solid after decades. With the old models the issues are often known - but this is often something like years after end of production.
Hard to tell which of the two brands is better - both are considered good but expensive.
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I have the EDUX1002G and I am opening it all the time, using a heat gun to remove components /...
Hi. I haven't opened the unit and will not do it until the warranty lasts.
When it's over in about 1y then I might consider that.
I want to have it in spec too, so just heating random parts probably won't end so well for that.
I fixed one of my older Keithley 2015 6 1/2 digit meters and it's not so easy to do a pristine job. Later you will wonder why it drifts so much.
Of course, a 6 1/2 meter is quite easy to screw up in that sense.
Took effort and planning to get good result.
So I'll reserve that option for later.
Regards,
Sorry for confusing you, what I suggested is that you might have a unit that is the exception. I was torturing my unit in an attempt to hack it to the full DSOX model as a learning exercise and I was not able to break it. I am sure it is by now out of specs, but it suits well my needs, and I do not recommend it to anyone who needs to use the instrument for professional test and development.
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Personally, I've seen tons of past-warranty Tek and HP/Agilent/Keysight scopes and test equipment floating around labs and staying stable as the workhorse you expect them to be.
Yup, sounds like what I had in mind when deciding. A rock-solid workhorse...
And I do fully acknowledge that the service quality was good with the first issue. No complaints there.
Obviously the right thing to do is to repair it under warranty.
My biggest worry is that the luck will continue and I will see 3rd time of this.
Especially given that the first time, they replaced modules rather than repaired anything.
Ergo, I must say I've lost confidence.
I need some upgrades (BW and Digital channels) but shelling out for upgrades looks like a bad idea right now.
Thus I'm stuck with a stupid choice: take the risk that 3rd time wont happen or go for a new scope. I mostly lose either way.
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My biggest worry is that the luck will continue and I will see 3rd time of this.
Especially given that the first time, they replaced modules rather than repaired anything.
Ergo, I must say I've lost confidence.
Many years ago when IBM was still making Thinkpads mine developed an intermittent fault. I sent it in and they worked on it but after I got it back, the fault reappeared. I contacted them and explained the history, and then sent it in again. The second time they replaced pretty much everything except the case and it never failed again.
I'd suggest that you contact Keysight and explain the history of your scope problems and repairs. A good service organization, which I would expect Keysight to have, should escalate their effort to make it right for you.
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I have used a variety of scopes in my career, agilent always provided a good service (although I did have a lot more issues with their equipment) and Tek did too but I only ever had 1 issue with theirs. :-+
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I have its (lots) older brother, an Agilent dsox3024 , 2 feature upgrades, 2 firmware upgrades (it now calls itself a Keysight) and usual 'dumb stuff' re ground clip (twice FFS!)
Still going strong - Daniel B's offer sounds good.
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I have the EDUX1002G and I am opening it all the time, using a heat gun to remove components, solder new components, exchange components... and it boots and works everytime I need. Maybe you have case of cold solder on one of the large ICs with BGA...
That was my first thought, maybe a batch had some issues with BGA soldering?
Very unusual to get 2 units fail, but I guess someone has to unfortunately be the outlier on the bell curve.
BTW, my old first (pre-production?) batch Keysight 3000 failed after about 5 years. A sample memory error message, but otherwise functionally no problem that i could find. They replaced it with the 3000T.
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Thus I'm stuck with a stupid choice: take the risk that 3rd time wont happen or go for a new scope. I mostly lose either way.
You don't lose anything by trying a 3rd time, it doesn't cost you cent, and in all probability will eventually be the "workhorse" you expect.
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As for Tek's failing, there have always been an awful lot of Tek TDS series scopes "for repair" on ebay. They might have even been a bit infamous for failing?
As for modern designs, I'm not sure there is any real data on either brand.
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It is hard to judge reliability based on the number of broken numbers without having access to sales figures for that particular model. That model may also just be very popular., or popular in an industry that dumps them in a way that they end up on eBay (like government). Tektronix did have a few models of digital scopes with bad 'surface mount' electrolytics that would invariably leak, but that is a long time ago.
I do not think that anyone that is allowed/willing to share it has sufficient data to compare the reliability of the two companies.
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Having spent many years in failure analysis, I've seen some multilayer boards which develop intermittent via contacts.
In my experience, if a board has developed an intermittent via because of a poor plating, even if you correct that particular via, then another one may become intermittent later.
Thus...I agree with the other posters. Have Keysight replace it.
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Wow, I'm sorry to hear you've had such a rough time. I'm sure it doesn't make you feel any better, but to have two failures like this is extremely unusual for our scopes. If you need a loaner unit to hold you over while yours is in the shop or have any trouble with the repair folks let me know.
Thanks for the offer.
I posted the issue today to Keysight customer service, Finland, which is closest to my area. Let's see how they will do.
I can survive a couple of weeks without the Keysight scope as I can borrow a cheaper scope from someone.
I must admit that I feel a little bit stupid asking this cheaper scope for a loan to back-up my Keysight one...
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Not very rational to use what is clearly an extremely rare double failure, made worse by your inexplicable decision to not even contact the manufacturer until it became a serious inconvenience, as a means to suggest Keysight quality is poor.
Sounds like a child's tantrum, threatening to throw her toys out of the crib.
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As for Tek's failing, there have always been an awful lot of Tek TDS series scopes "for repair" on ebay. They might have even been a bit infamous for failing?
These are entry level & Edu scopes which probably biases the eBay listings. Sourcing parts to repair them is difficult (replacing a main board is cost prohibitive in this class).
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As for Tek's failing, there have always been an awful lot of Tek TDS series scopes "for repair" on ebay. They might have even been a bit infamous for failing?
As for modern designs, I'm not sure there is any real data on either brand.
There was a well-known issue with leaking caps on some models.
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As for Tek's failing, there have always been an awful lot of Tek TDS series scopes "for repair" on ebay. They might have even been a bit infamous for failing?
As for modern designs, I'm not sure there is any real data on either brand.
There was a well-known issue with leaking caps on some models.
The color screen on these is also a weak point but let's not forget that most of the TDS500/600/700 series are over 20 years old.
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I have a Keysight MSOX3054A and a Tek MDO3054 on the bench permanently.
Of the two the Keysight is a joy to use compared to the Tek, which has a slow and unintuitive UI which I find gets in the way of my workflow.
There are a few things the Tek is better at, but they tend to be edge cases. I find that there are many more compromises on the Tek compared to the Keysight, mostly around the UI such as the way certain functionality is modal, i.e., you can only do certain things in certain modes, but mostly it's the sluggishness and inconsistent way you accumplish things.
In short, I would see if you can spend some time with the Tek before you buy. Maybe you'll love it, but I wouldn't bet on it!
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This post to me smells of rotten troll fish. if false, its probably an isolated incident, just move on and get it replaced many members here use their stuff (including me MSOX 3104T) and its pretty dam good. statistically if someone ran all the EEVBLOG comments through some machine learning the results will show a high bias towards Keysight for obvious reasons.
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As for Tek's failing, there have always been an awful lot of Tek TDS series scopes "for repair" on ebay. They might have even been a bit infamous for failing?
As for modern designs, I'm not sure there is any real data on either brand.
There was a well-known issue with leaking caps on some models.
The color screen on these is also a weak point but let's not forget that most of the TDS500/600/700 series are over 20 years old.
Who knows what units will be reliable 10 or 20 years from now? It's only in hindsight that we can say whether or not any particular model or series was a workhorse, or if it will develop some common failure mode across the entire series. I would say make due with what you've got for now, and only move to replace once the repair costs start making it worth getting something new.
As for older series, from what I have seen on Ebay, many of the green CRT TDS 300/400s seem to be still okay, and seem to have a lower failure rate. The TDS 5/6/700s seem to be the ones that have almost all failed.
I would consider the TDS's high failure rate after 20 years to be on the short side for a high-tier test equipment OEM. Especially when one considers that there are still plenty of >30 year old Tek 22XX and 24XX scopes still kicking around. With a bit maintenance and re-capped power supplies, many of them look ready to go another 10 or 20 years at least. Whether it was justified or not, I think the high failure rate of the TDS series is often seen as a stain on Tek's otherwise very good reputation.
On the Keysight side, the old HP 54XXX scopes seem to have a relatively good track record for reliablity. To the best of my knowledge, a good percentage of them are still working with little or no maintenance. The only other HP scopes that come to mind are the old 1740-series scopes, which I don't know much about. Any older than that any you are getting into hybrid vacuum tube territory.
On a side note, I've always been curious about the Tek 7XXX mainframe scopes. Anyone know if they are considered reliable? Most of the ones you see on ebay are incomplete, and I only know of a handful that are out in hobbyist hands.
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On a side note, I've always been curious about the Tek 7XXX mainframe scopes. Anyone know if they are considered reliable? Most of the ones you see on ebay are incomplete, and I only know of a handful that are out in hobbyist hands.
They use early (fragile/stressed) semiconductors and when they fail it rips through lots of parts and makes it uneconomic to repair. There are a few niche low bandwidth applications (7A22) for them but its possible to mostly replace them with mid range scopes these days. That said they're still good to use if you have one in working condition.
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They use early (fragile/stressed) semiconductors and when they fail it rips through lots of parts and makes it uneconomic to repair. There are a few niche low bandwidth applications (7A22) for them but its possible to mostly replace them with mid range scopes these days. That said they're still good to use if you have one in working condition.
Good to know. I figured there was a reason why you don't see more of them.
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On a side note, I've always been curious about the Tek 7XXX mainframe scopes. Anyone know if they are considered reliable? Most of the ones you see on ebay are incomplete, and I only know of a handful that are out in hobbyist hands.
One of the 3 scopes on my bench is a Tek 7904 in good working condition. Never had to do anything to the mainframe. There have been some Tantalum failures in plugins that I've needed to recap.
Other 7xxx scopes that I have but rarely use are 7704, 7854, R7903, and 7844. The 7844 probably needs some new capacitors as it acts up when first turned on after sitting a long time. The others just work. The 7704 was my first 7xxx scope from way back in the early days of eBay. My most recent 7xxx is the 7854 with cart, purchased a few years ago from the Tek surplus store.
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By now, I think many if not most of the DSO/MSO 6000 series scopes have had to be repaired by the factory due to a boot failure issue. Keysight did a good job taking care of mine when it failed, repairing and returning it quickly, and there have been no additional failures over the past few years. I'd have no problem recommending them.
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^^^ This ^^^
Even the best companies will turn out a lemon from time to time.
The difference between a good and a poor company, is how quickly they acknowledge the issue, and the steps they take to remedy that.
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On a side note, I've always been curious about the Tek 7XXX mainframe scopes. Anyone know if they are considered reliable? Most of the ones you see on ebay are incomplete, and I only know of a handful that are out in hobbyist hands.
I have a handful of them on my own... They do need repairs from time to time. My 7704 broke down three times i think. But always easy fixes (tant cap shorted, bridge rectifier failure on the mains side (fuse really goes bang) and some arcing at resistors in the HV area). Same for the plugins, can be fixed. Some contain tek specific relays that fail a lot and are hard to replace (footprint wise). I did replace the PS caps on a number of mainframes and have some spare around. Usage is with specific plugins. 7A22 indeed and also 7A13. Then 7S11/7T11 sampling plugins and a 7L5 spectrum analyser. Just for the fun of it, not because i really need them :) Nearly forgot to mention a 7612D digitizer. Jup, TEA....
If you need 7A22 functionality, i suggest to get the TM5xx variant and connect it to a modern scope. Best of both worlds.