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David, have you all this scope, or you have returned the Owon and Tekway?
The OWON and Tekway have gone back, I only had them for a day or two.
Note to self: If you want Dave to post his review ASAP set a return date on your stuff.
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David, have you all this scope, or you have returned the Owon and Tekway?
The OWON and Tekway have gone back, I only had them for a day or two.
Note to self: If you want Dave to post his review ASAP set a return date on your stuff.
Yeah but Dave does not return stuff mailed to him. He's said that at least once or twice. I think the scope he got was borrowed from a local supplier. I don't think it was new because it had a sticker of the company on the side that looked like it had been partially caught in the groove on the inside or closed on it. It might have been a shelf display. -
The distributor is weird.
That distributor is honest. You can tell he doesn't cheat the "Dave test". After all he will get a lot of customers when he finally scores the big one and gets Daves thumbs up on some product
Rigol got huge bump in sales thanks to Dave, and that was before eevBlog channel got popular.
I worked for PC parts distributor over 10 years ago (third in sales in my country, sole distributor of some big brands at the time etc) and it was common for sales/PR people to come down to the service area basement and tell us to find a "perfect unit" because some IT Paper had a hardware shootout. All of a sudden shitty brand CRT monitor/CDrom was scoring perfect marks.
Thanks for the vote of confidence in our honesty. It is appreciated. To set the record straight here's the history of this instrument.
It was not a new unit.
It had been sold previously and had developed a problem while the customer had it.
The company that bought it needed it for their business and they were unable to work without it.
We did not wait for a spare mainboard to repair it.
We gave the customer a new scope from our stock to get him back to work immediately.
When we got the replacement board from Tekway we fitted it in this unit.
That is the reason the serial numbers on the screen and on the back are different.
(If Tekway is reading this, my suggestion to them is that they should also send distributors a new serial number label when they send a replacement main board.) So that's the history of that one.
Anyway, because the scope had been used already it obviously could not be sold as new, so we just use it as a spare scope in the office or for demo. Dave wanted some low-end scopes to play with so we gave it to him with the Owon.
First impressions are lasting impressions and Dave's first impression of the TEKWAY started off well but then deteriorated and not all of that was attributable to the scope. What I thought was missing or was not considered is product positioning in the marketplace. (this applies to the OWON as well)
Personally, I think because Dave was in a rush as we needed it back here, there was not as much thought put into what he was doing. A good example is the X-Y situation. "Seek to understand not to criticise" is generally what engineers do and not a lot of that was present in either of the "reviews."
We've sold a lot of these Tekway scopes and we've had 2 failures (this was one of them) and we've had no negative customer feedback.
What was surprising in the review was the pulse response of the OWON. For a sub-$1500 scopes with 300 MHz it was excellent. It represents value for money in it's price bracket. It's got all the basics a scope needs for waveform capture and viewing in terms of Bandwidth, Sample Rate and Memory Depth. Who else offers a 300 MHz with similar specs for under $1,500?
As for the TekWay no-one I know of no company that offers a 100 MHz scope for under $500 with a hi-res display as good as the Tekway including good basic scope specs and some neat measurement functions.
As said above, I think we saw Dave's impressions from a hurried perspective. I don't disagree with the pulse response issue, it certainly could be better, but on-balance (and that's what was missing) one area of weakness is certainly overcome by the positives when this sub-$500 scope is positioned properly in the marketplace. And if you want the best of everything especially signal fidelity then move up the price bracket and buy Agilent. Dave know's and loves the X-series and spent a lot more time reviewing it!
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As said above, I think we saw Dave's impressions from a hurried perspective. I don't disagree with the pulse response issue, it certainly could be better, but on-balance (and that's what was missing) one area of weakness is certainly overcome by the positives when this sub-$500 scope is positioned properly in the marketplace.
I'll have to disagree with Charles here.
It wasn't just the crappy pulse response. It was also the very substantial trigger jitter issue, plus the firmware lockups.
I can look past the firmware lockup issue, that can be fixed in software, but I simply cannot recommend a scope that does not give measurement confidence in the signal you are viewing. The trigger issues and pulse response on their own are enough not to get this scope a recommendation. But it has a double whammy there + firmware issue.
And I was considering the market space and competition. In Oz the Rigol 1052E is $100 cheaper for the same bandwidth, and has none of these issues, it is a rock solid and well proven device.
Sure, the Rigol has a smaller screen and few less features, but is that worth trading measurement confidence for? In my book, no way, but each to their own.QuoteAnd if you want the best of everything especially signal fidelity then move up the price bracket and buy Agilent. Dave know's and loves the X-series and spent a lot more time reviewing it!
The sub $400 Rigol has excellent signal and trigger integrity.
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sorry Dave, but that bullshit what you said. Maybe you don't know, or just don't care, but when you would spend a minute to compare schematics of Rigol and Tekway you would recognize that there can't be difference in signal/trigger. Jitter, well, when you ever did FPGA design you would know what jitter is possible on FPGA when using non-dedicated clock out pin, and btw, Rigol is using even 5 clocks, where Tekway only 4 clocks, so the chance to get more distortion due jitter from ADC clock is even higher on Rigol.
But anyway, it was your first impression^^ so actually didn't mater if that Tekway was broken or not or if ti was one of these unit what didnt have nice response after hack or not factory calibrated or what so ever (because a working DSO is response like on my pictures).
I remember i got brand new MB E350 few years ago, and few days after i got it it stopped while i was about to overtake another car, no steering, no anything, i just made to brake/slow down to hide my ass between another car and some trees. Sure MB updated firmware, the car was again ok for some time, then that shit happened again. It was a good car, but i repalced it after that by another brand, and honestly i tooks 2-3 years for me to trust MB again. So yes, my first impression was "no thanks" even if i was only in the 2% of broken firmware group, but that wasn'T important for me but only my personal first impression. -
Firmware in a car.
I would rather use this Lada instead.
Maybe I still live in early 1990s...
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My car has 5 sets of firmware in it. So far ( touch wood) no issues with that part, just the usual mechanical parts wearing out.
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To set the record straight here's the history of this instrument.
Never give Dave a potentially faulty scope. Always give him a new unit, if you want a positive review.
It was not a new unit.
It had been sold previously and had developed a problem while the customer had it.
The company that bought it needed it for their business and they were unable to work without it.
We did not wait for a spare mainboard to repair it.
We gave the customer a new scope from our stock to get him back to work immediately.
When we got the replacement board from Tekway we fitted it in this unit.
That is the reason the serial numbers on the screen and on the back are different.
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sorry Dave, but that bullshit what you said.
I can only base my opinion on the scope I tested, anything else would be 2nd hand opinion.
That's what this forum is for, if you have experience with the scope add your own opinions.
Then based on that info, people can make up their own minds.
I have facts and video evidence of why I said what I said about the Tekway, it was not bullshit.
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Never give Dave a potentially faulty scope. Always give him a new unit, if you want a pisitive review.
To be fair, Charles had no way of knowing that it would have response issues, trigger issues, or firmware lockups unless he tested it in the exact same way I did.
By all accounts other people have had the same issues, and it seems to be a bit of "pot luck" about which hardware/firmware combo you get. -
Well I see a few ways where this could go.
Option A: Nothing is done and the review stands.
Option B: If Trio is close enough to where Dave is, maybe he could drop by with his camera and repeat the same test on another unit (if available)
Option C: Trio or Tekway mails a unit to Dave for a follow-up test.
Option D: Someone else repeats the full test on video and Dave provides a link to it in his video.
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sorry Dave, but that bullshit what you said.
I can only base my opinion on the scope I tested, anything else would be 2nd hand opinion.
That's what this forum is for, if you have experience with the scope add your own opinions.
Then based on that info, people can make up their own minds.
I have facts and video evidence of why I said what I said about the Tekway, it was not bullshit.
i didn't spoke about what you saw on the DSO which you tested, that was for sure crap.
The statement "you said bullshit" is related to "Rigol is having better"
- excellent signal
- trigger signal
- jitter
- pulse response
This is because as already said in Tekway thread, both Rigol and Tekway have:
- same frontend
- same trigger circuit
- same mux/opamps/ref
- same FPGA
- same ADCs
so from a signal flow point of view there is no winner, both are exact good/bad, the signal from BNC to FPGA is looking on both devices same. But hey, maybe Rigol is soldered by chinese virgins giving the DSO some magic ? I don't know, but as EE i doubt that. -
maybe Rigol is soldered by chinese virgins giving the DSO some magic ?
That's it. Her name is Anna Ohura.
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maybe Rigol is soldered by chinese virgins giving the DSO some magic ?
That's it. Her name is Anna Ohura.
Perhaps she can not get even visa for mainland China.
If japanese or half japanese people go to working in some chinese factory there come perhaps some problems.... depends...
When someone talk about chinese working in chinese factory and you show japanese public w....e picture... really difficult to understand. -
So I'm a little confused. The scope had problems and was returned. Tekway sent out a board intended to fix the scope. Scope was sent to Dave for review and it he finds problem after problem. Someone else claims that the reviewed scope is just faulty and that the scopes have no issues....even though this particular scope originally had issues, and the new board that was sent out to fix them also has issues.
What have I missed? It's not Dave's fault he has a crap scope. Maybe someone out there will take a brand new, off the shelf, factory sealed scope and send it to him for test. What else should he do? Tell everyone to disregard what he's found because someone claims the Tekway and Rigol should theoretically have the same performance? Who are we going to believe...the specs or our lying eyes? Whatever front-ends, ass ends, book ends and whatever other ends the scopes share, this isn't a verification by inspection. It's a hands on review of what was believed to be a representative sample.
The day Dave starts tip-toeing around bad performance is the day his blog becomes useless. Someone send him a new scope. I'm sure he's anxious to see one that's not full of excuses.
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The Rigol and the Tekway may even have similar front ends, but zillions of other factors may be factored and possibly cause the problems seen in the review.
The one that strikes me the most is temperature. How several other manufactures see the need (and added costs) to slap a damn fan to push cold air into the case (or pull it out, it doesn't matter) while Tekway gets by without it? One of the easy way out is to clock down the main processors and digital circuitry to reduce heat from them and from the power regulators (could explain the slow GUI, maybe?). This is a potential candidate to cause runtime bugs if the firmware is not properly validated to run in this new frequency (which could include faulty reads from the interface with the analog front ends, but I am not an expert in this).
Of course I don't have the information tinhead has, but in the light of the review that seemed very plausible.
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Of course I don't have the information tinhead has, but in the light of the review that seemed very plausible.
i actually said everything what new to be said, it is not that hard to get one or two pages back and read my technical explanation of that what Dave saw on the test unit.So I'm a little confused.
yes you are, completly.
ok, i will shot a short video, it seems that some ppl need visual things and not just few lines of "technical crap" text.
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Someone else claims that the reviewed scope is just faulty and that the scopes have no issues....even though this particular scope originally had issues, and the new board that was sent out to fix them also has issues.
What have I missed?
That "someone" is tinhead, no need to use the common backstabbing tactics of referring to "someone" and THEM.
And what you missed is that tinhead doesn't say these oscilloscopes have no issues. For a year or two he is raising hell with Hantek/Tekway to get stuff fixed. What he is saying is that, based on his experience with multiple hardware and multiple firmware versions, that particular oscilloscope did not behave like what is considered "normal" for these oscilloscopes. -
Someone else claims that the reviewed scope is just faulty and that the scopes have no issues....even though this particular scope originally had issues, and the new board that was sent out to fix them also has issues.
What have I missed?
That "someone" is tinhead, no need to use the common backstabbing tactics of referring to "someone" and THEM.
And what you missed is that tinhead doesn't say these oscilloscopes have no issues. For a year or two he is raising hell with Hantek/Tekway to get stuff fixed. What he is saying is that, based on his experience with multiple hardware and multiple firmware versions, that particular oscilloscope did not behave like what is considered "normal" for these oscilloscopes.
Backstabbing? I just didn't see any reason to really call him out because it's not anything personal about him. I read where he's fighting Tekway to get the issues fixed, but I also read where he calls "bullshit" and basically says Dave should base his opinion on some schematic, not the actual scope.
Geez...just get him non-broken scope to test.
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- same FPGA
That one's a bit of a stretch, the only thing you can get on that is theoretical maximum gate speed, but they have to be programmed. -
i actually said everything what new to be said, it is not that hard to get one or two pages back and read my technical explanation of that what Dave saw on the test unit.
ok, i will shot a short video, it seems that some ppl need visual things and not just few lines of "technical crap" text.
Don't be a jerk; I am not your short attention span person that can't read more than five lines of text and can't understand what was just read - I meant all the information and experience you gathered by plowing through the circuits and comparing board revisions and model numbers. I am not against you or the Tekway brand, I am talking about the reviewed scope and a possible explanation for what may be happening with it (it is clear from my post).
I stand for what I have said before, where your explanation about the front end and hardware revisions only covers part of the problem. All the other problems related to the GUI and the lockups can be (up to a certain extent) be explained by what I said - even some signal problems, but as I mentioned before I am not an expert in this particular area.
Therefore, please take off the Tekway shirt and keep a cool attitude. I am discussing the issues seen on the review, not fighting for who or what is better or not. If Tekway is reading these lines, they will surely get something out of this discussion, either figuring out a better system in dealing with repairs done by their official distributors (as suggested by Trio) or recalling older and less performing units with hw1005 hardware. -
- same FPGA
That one's a bit of a stretch, the only thing you can get on that is theoretical maximum gate speed, but they have to be programmed.
it didn't matter what "program" inside the FPGA, the i/o jitter on non-dedicated "clock out" pins will be always the same. Sure, i/o standard could have influence as well, but both DSO are using the same ADC / parallel clock termination so we can ignore it. It depends as well on input clock jitter, and for sure was Rigol smart and used dedicated quarz+inverter combination to archieve low jitter, but then they ruined by using another one inverter gate to drive the FPGA. Tekway is using directly crap quarz oscillator.
Whatever both used, it is not good enought^^. No matter what design inside FPGA, the output clock for ADCs will have max 650ps period jitter. So even when we ignore the i/o skew on FPGA, we will have up to 1.3ns period jitter worst case between 2 output clocks. Rigol is using 10ADCs, so 5 clocks (+5 inverted). Tekway is using 8 ADCs, so 4 clocks (+4 inverted). For Rigol it means when sampling with 1GS/s each of the 100MHz clocks is delayed by 1ns, and for Tekway as well 1ns (but clocks at 125MHz). Sure, this are max values, typical you can get less jitter, but it does not matter for product comparision as both products affected in same way. Sure, Rigol can have total higher jitter, but Tekway can have higher gain drift due ADC overclocking.
So you can see pure from hardware point of view you can have only crap results on both^^ The trick both manufacturer using is to check when after rising edge of ADC 1 ->8 (10) the data is showing zero crossing. These values are then taken to build a skew table to allign the sampled data. But of course the interleave distortion is already in the signal (you can observ on both models that when using single shot a RF wave is more distroted in single shot than when in run mode, for single shot you can't filter out any variation to skew table, for run mode there are some tricks to made signal looking better that it is). The way to work with interleaved ADCs is to measure during calibration the skew (which is different between devices due parts/pcb variance) and to allign all clocks to get same zero cross from all ADCs, but never ever to sample with bad clock and to allign the data afterall. But that's different story. I don't know by 100% who was the first with that idea, from the information about release dates and teardown i would say Instek did it first (and btw, they did it better), then Rigol adapted it into their E models. Short after that others (Tekway/Siglent/ATTEN) adapted it as well. You might find small differences here, like different opamp in S&H on Siglent to reduce the drift on cold DSO, but all these modifications are more or less too small to talk about real differences in signal/trigger integrity.
And yes, firmware A can maybe allign the crap data better than firmware B, as well device A could be better calibrated as deivce B because the technician plugged the cable properly into BNC, and manufacturer A can implement better algos to filter variations as manufacturer B did. But that's are things applied afterall. Knowing hardware on both models, and knowing how they work i know that one can't say "Rigol has excellent signal and trigger integrity" and "Tekway have trigger / jitter issue" at same time. And of course other models using similar/same hardare are affected as well (Siglent/ATTEN).
And once again, there was nothing wrong with Dave's review, he didn't cheated (on purpose'), so yes his statement based on his result is ok. But on the other side i (and other as well) do have working models and i/we know what one can achieve on these DSOs. So there is difference between "Dave's DSO" and "all these DSOs" and all i'm trying to do is to stop people from seeing only "back and white" when there is a rainbow on the sky^^.
I said as well that Tekway/Hantek produced lot of crap in last 3 years (e.g hw1005 disaster or some FPGA design versions), i did said as well that they do firmware issues (sometimes they simply sleeping, like on the long memory in XY trigered mode ... that should be not possible together, but it is and it does produce overflow and dso.exe is crashing^^), but i said as well that they working on it. It is not that the firmware is not sufficient to do most of the work, sure, it is, but there are things like digital filter or equ mode sampling missing/disabled, as well few limitations like zoom in dots mode is not "exact" in last 3 zoom stages. And finally i did said that for a year of so Tekway/Hantek populated very "unfortunate" combination of resistors in frontstage, but this is still within specs on non-hacked DSO but 3-5dB deviations on hacked DSOs - and i did said how this can be fixed (for 8USD).
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And once again, there was nothing wrong with Dave's review, he didn't cheated (on purpose'), so yes his statement based on his result is ok. But on the other side i (and other as well) do have working models and i/we know what one can achieve on these DSOs. So there is difference between "Dave's DSO" and "all these DSOs" and all i'm trying to do is to stop people from seeing only "back and white" when there is a rainbow on the sky^^.
I understand all that you're writing - but the question remains - when you buy a $400 - 500 product (or get one for review), should you have to search and install the perfect combination of FW for your hardware in order to prevent hangs and crashes - and make it 'achieve' the performance you expect it should have out of the box? -
I understand all that you're writing - but the question remains - when you buy a $400 - 500 product (or get one for review), should you have to search and install the perfect combination of FW for your hardware in order to prevent hangs and crashes - and make it 'achieve' the performance you expect it should have out of the box?
- because not everybody can spend 1000$ (EU price) for better, but still not bug free DS2072
- because all the others in < 1k USD have issues/not that good things as well, like smaller display, 3-4 times higher ground
noise (after DIY fix!), less functions, smaller display resolution and finally less support from manuafcturer or community.
these Tekway/Hantek "P" models, with 24k memory, they costs 260USD delivered to EU, that's 240EUR in Germany (with tax).
When one buy such DSO and spend 8EUR for other resistors, then it didn't matter how bad the forntend was populated originaly,
such DSO would have perfect response up to 220MHz, no issues with "long memory is slow", no "XY mode and long memory slow",
no "firmware hangs while long memory and alterate trigger enabled". So what left from Dave's review? Nothing.
But even a Voltcraft/Hantek/Tekway for regular price can be, even if you got crap version, fixed for few bucks. Yes, why i have to fix
DSO when there are others ... wait, what others? Owon? Sure, 50USD for replacement PCB and 50USD for shipping, lol, and then the gnd noise is still 3-4 times higher than on Tekway. Sure, such B/BMV/MSO models will still be ass slow responding when long memory enabled,
but that's different story (nobody is forcing ppl to enable all the memory all the time, but if then buy Owon, simple).
The whole game will change a bit when Rigol DS1000Z will be available, but still, you will not get any other DSO with big screen, fast update and 200MHz for 250EUR. Sure, one need maybe to solder few resistors, but i think a DSO will be anyway used by ppl who know what to do with soldering iron? I hope so.
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The whole game will change a bit when Rigol DS1000Z will be available, but still, you will not get any other DSO with big screen, fast update and 200MHz for 250EUR.
Maybe we won't have to wait for too long: Franky is just showing off his new toy here