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EEVblog => EEVblog Specific => Topic started by: EEVblog on September 02, 2015, 06:59:34 am

Title: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: EEVblog on September 02, 2015, 06:59:34 am
Take a look inside the 500MHz 4 channel Teledyne Lecroy WaveJet Touch 354 oscilloscope.
a.k.a An Iwatsu DS-5600, made in Japan
http://cdn.teledynelecroy.com/files/pdf/wavejet-touch-fact-sheet.pdf (http://cdn.teledynelecroy.com/files/pdf/wavejet-touch-fact-sheet.pdf)
https://www.iti.iwatsu.co.jp/en/products/ds/ds5600/ds5600_top_e.html (https://www.iti.iwatsu.co.jp/en/products/ds/ds5600/ds5600_top_e.html)
Datasheets:
Ti ADC08D1000 1GS/s ADC: http://www.ti.com/lit/ds/symlink/adc08d1000.pdf (http://www.ti.com/lit/ds/symlink/adc08d1000.pdf)
LMH6518 Variable Gain Amplifier: http://www.ti.com/product/lmh6518 (http://www.ti.com/product/lmh6518)
4 bank Synchronous DRAM: http://www.issi.com/WW/pdf/42-45S32200E.pdf (http://www.issi.com/WW/pdf/42-45S32200E.pdf)
Renesas SuperH Processor: http://www.alldatasheet.com/datasheet-pdf/pdf/249590/RENESAS/R5S76700.html (http://www.alldatasheet.com/datasheet-pdf/pdf/249590/RENESAS/R5S76700.html)
Lattice ECP2 FPGA: http://www.digikey.com.au/product-detail/en/LFE2-70E-7FN672C/220-1205-ND/2731506 (http://www.digikey.com.au/product-detail/en/LFE2-70E-7FN672C/220-1205-ND/2731506)
Lattice Mach XO CPLD: http://www.dataman.com/media/datasheet/Lattice/MachXOFamily.pdf (http://www.dataman.com/media/datasheet/Lattice/MachXOFamily.pdf)

https://www.youtube.com/watch?v=WTK4CgYbXEQ (https://www.youtube.com/watch?v=WTK4CgYbXEQ)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Muxr on September 02, 2015, 07:01:58 am
Nice one Dave! I really liked the internal design of this scope. Would like to see the related mini review of the scope. I guess that vid is uploading?
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: EEVblog on September 02, 2015, 07:15:03 am
Nice one Dave! I really liked the internal design of this scope. Would like to see the related mini review of the scope. I guess that vid is uploading?

Still editing.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: f4eru on September 02, 2015, 07:51:40 am
Hello,

Concerning the link between both BNC footprints, i think I know what's happening :

the two footprints marked 11J1 & 11J4 are for U.FL or similar connector sockets.

Either a coax link was foreseen, and has been cost optimized to a SMD placed custom link, or there was to be two connectors comming from the ADC boars, one for each BNC, and at a late stage in the design they decided to use the circuitry inbetween that was only foreseen for the second connector, and they changed to that arrangement...

Either way, the custom link thing seems to be properly dimensionned as a 50 ohm transmission line, so it's more than just a quick bodge.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: teerosheyal on September 02, 2015, 08:01:04 am
The area of the connectors that you didn't knew what the heck they were doing? they made an optional 2 BNC connectors, 2 U.FL or W.FL connectors (almost the same footprint) for microcoax, and basically jumpered the 2 channels using a Costume-made bar covered with tin (for solderability) from the two center pins (signal) of the cables.
This is what you call an over-engineered Japanese bodge-wire ;)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: daqq on September 02, 2015, 08:42:55 am
Thanks for the video Dave.

Funny, I just bought a waveJet 314 and was looking to do a teardown. Now I might do a comparative teardown  :)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: salviador on September 02, 2015, 09:50:51 am
Lecroy It has little memory than rigol and the cost is too high !
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: bktemp on September 02, 2015, 10:02:57 am
How old is this scope?
It looks like the ADC is obsolete and every modern FPGA supports at least DDR3 SDRAMs. I was really surprised to see SDRAMs as acquisition memory.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: daqq on September 02, 2015, 10:06:32 am
Quote
How old is this scope?
It looks like the ADC is obsolete and every modern FPGA supports at least DDR3 SDRAMs. I was really surprised to see SDRAMs as acquisition memory.
The waveJet (354 included) series was available in 2007.

http://www.testoon.com/fichiers_guide/EN/LeCroy_2007_2008_Catalog_en.pdf (http://www.testoon.com/fichiers_guide/EN/LeCroy_2007_2008_Catalog_en.pdf)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: BravoV on September 02, 2015, 10:09:43 am
Hmmm .....  :popcorn:

(https://www.eevblog.com/forum/blog/eevblog-790-lecroy-wavejet-354-touch-oscilloscope-teardown/?action=dlattach;attach=168880;image)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: AlfBaz on September 02, 2015, 11:11:19 am
They seem to make a lot of use of 45 degree (and some, arbitrary) angle component placements. Not something you see a lot of these days.

As for giving Iwatsu all the design cred, I'm not to sure. Ive pulled apart a lot of old real lecroys and they all make use of those shielding bars between front end inputs. In fact, just from the look of the general circuit topology, the design is very reminiscent of most 9384 series lecroy motherboards
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: dr.diesel on September 02, 2015, 11:17:52 am
The music at the end during reassembly for some reason reminded me of this song:   O0

http://youtu.be/8inB7FAPHc4 (http://youtu.be/8inB7FAPHc4)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: EEVblog on September 02, 2015, 11:19:37 am
How old is this scope?
It looks like the ADC is obsolete and every modern FPGA supports at least DDR3 SDRAMs. I was really surprised to see SDRAMs as acquisition memory.

The scope itself is only a year old, but the design likely dates back several product generations.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 02, 2015, 01:52:00 pm
How old is this scope?
It looks like the ADC is obsolete and every modern FPGA supports at least DDR3 SDRAMs. I was really surprised to see SDRAMs as acquisition memory.

The scope itself is only a year old, but the design likely dates back several product generations.

The WaveJet 300 Series is pretty old, it was introduced by LeCroy at the end of 2006.

There actually are three iterations of this scope: the original WaveJet 300 (white case, 2006-2008), the WaveJet 300A (black case, made from 2008 to 2014), and the "new" WaveJet 300T shown in the video which came out last year and is a essentially 300A with touchscreen.

They seem to make a lot of use of 45 degree (and some, arbitrary) angle component placements. Not something you see a lot of these days.

As for giving Iwatsu all the design cred, I'm not to sure. Ive pulled apart a lot of old real lecroys and they all make use of those shielding bars between front end inputs. In fact, just from the look of the general circuit topology, the design is very reminiscent of most 9384 series lecroy motherboards

The similarity with older LeCroy scopes is no surprise since the WaveJet is another result of LeCroy's cooperation with Iwatsu which started the '90s when LeCroy rebadged Iwatsu analog scopes. Later when LeCroy was looking for a manufacturer for its new WaveRunner LT lower high-end scopes they increased the cooperation which included quite a bit of knowledge transfer about hardware design to Iwatsu, although most of the scope was designed by LeCroy. The WaveRunner LT was a success and so the cooperation continued for the WaveRunner2 LT (lower high-end) and the WavePro 900 (upper high-end), again mostly LeCroy designs. Sales were also divided, with Iwatsu selling the scopes under their name in Japan, and LeCroy selling them under their label on the rest of the world.

At the same time (end of the '90s), LeCroy also bought in a small Iwatsu-designed portable entry-level DSO with b/w LCD and resold it under the LeCroy brand as LiteRunner LP. However, being made in Japan it was pretty expensive, especially for its price segment, and it didn't sell very well. In the end it was cancelled around 2001/2002 if I remember right.

Three years on LeCroy again wanted to gain a foothold in the entry level, and so again teamed up with Iwatsu to come up with a new entry level scope, which was the WaveJet 300. However, like with the LiteRunner LP, LeCroy wanted to buy the scope ready to sell, so again this was a Iwatsu design (where they used the know-how they learned from LeCroy). When the WaveJet came out it had good specs, but as with the LiteRunner the problem was that manufacturing in Japan made the scope pretty expensive, and although the Dollar/Yen ratio isn't as bad as it used to be the problem with the WaveJet's price remained. For the Iwatsu-labeled counterpart this didn't matter much as Iwatsu was mostly aiming for the Japanese market only anyways.

The price was the main reason why LeCroy later teamed up with Siglent for a new entry level scope that was to be cheaper than the WaveJet, but the first models (sold as WaveAce 100/200) were awful, plagued by ridiculous firmware problems that Siglent couldn't fix in a timely manner, so the WaveJet remained. The successors WaveAce 1000/2000 were better, but not by much, which is why the WaveJet remained on offer, and subsequently even got a facelift (WJ300T) which includes a touchscreen and a few other improvements (a similar thing Keysight did with the DSOX30000T).

Today it's specs are outdated, but the WaveJet is still a very good and also very reliable scope, even though the UI is typical Iwatsu which means it's not the most intuitive or logical, and a bit old-fashioned.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: mux on September 02, 2015, 02:03:32 pm
I already commented this on Youtube but I suspect it will kind of be snowed under but...

Why in the world would they use TO-220 solder pin-mount heatsinks glued to those Altera FPGAs? That seems very odd. There are off-the-shelf little heatsinks for literally any package, available by the thousands. Why would they substitute a proper heatsink with what seems like either an afterthought or an emergency bodge?
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: dr.diesel on September 02, 2015, 02:06:03 pm
Why would they substitute a proper heatsink with what seems like either an afterthought or an emergency bodge?

If they just need to take the edge off, perhaps BOM reuse?
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: jancumps on September 02, 2015, 02:42:04 pm
The music at the end during reassembly for some reason reminded me of this song:   O0

http://youtu.be/8inB7FAPHc4 (http://youtu.be/8inB7FAPHc4)

Hey, I have that 12".
Shows my  age :)

(https://www.eevblog.com/forum/blog/eevblog-790-lecroy-wavejet-354-touch-oscilloscope-teardown/?action=dlattach;attach=168910;image)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Muxr on September 02, 2015, 03:13:49 pm
I already commented this on Youtube but I suspect it will kind of be snowed under but...

Why in the world would they use TO-220 solder pin-mount heatsinks glued to those Altera FPGAs? That seems very odd. There are off-the-shelf little heatsinks for literally any package, available by the thousands. Why would they substitute a proper heatsink with what seems like either an afterthought or an emergency bodge?
Probably an afterthought. They later realized there was not enough airflow on that side of the board and it needed a slight improvement in cooling.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: free_electron on September 02, 2015, 04:04:46 pm
The music at the end during reassembly for some reason reminded me of this song:   O0

http://youtu.be/8inB7FAPHc4 (http://youtu.be/8inB7FAPHc4)
Save Ferris !
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: free_electron on September 02, 2015, 04:12:24 pm
by the way , iwatsu have been in bed with 'others' too.

this may come as a shock :

http://www.ebay.com/itm/Iwatsu-V-810-Dual-Trace-Amplifier-Oscilloscope-Plug-In-Module-/151170338951?hash=item2332745087 (http://www.ebay.com/itm/Iwatsu-V-810-Dual-Trace-Amplifier-Oscilloscope-Plug-In-Module-/151170338951?hash=item2332745087)

even this one :

http://www.ebay.com/itm/Unlabled-Current-Probe-with-Iwatsu-4126-CP-512-Termination-Switch-Used-/400631625370?hash=item5d4781769a (http://www.ebay.com/itm/Unlabled-Current-Probe-with-Iwatsu-4126-CP-512-Termination-Switch-Used-/400631625370?hash=item5d4781769a)

Hioki is another one of these companies that 'gets into bed' with others .... look at their current probes ...
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: f1rmb on September 02, 2015, 04:44:00 pm


The music at the end during reassembly for some reason reminded me of this song:   O0

http://youtu.be/8inB7FAPHc4 (http://youtu.be/8inB7FAPHc4)
Save Ferris !

Anyone? Anyone?
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Hydrawerk on September 02, 2015, 04:59:18 pm

At the same time (end of the '90s), LeCroy also bought in a small Iwatsu-designed portable entry-level DSO with b/w LCD and resold it under the LeCroy brand as LiteRunner LP. However, being made in Japan it was pretty expensive, especially for its price segment, and it didn't sell very well.
It was Literunner LP142.
http://teledynelecroy.com/pressreleases/document.aspx?news_id=219&capid=107&mid=554 (http://teledynelecroy.com/pressreleases/document.aspx?news_id=219&capid=107&mid=554)
There is a manual available.
http://cdn.teledynelecroy.com/files/manuals/lp142section1.pdf (http://cdn.teledynelecroy.com/files/manuals/lp142section1.pdf)

Quote
In the end it was cancelled around 2001/2002 if I remember right.
Probably some units were manufactured and sold.

They were sold also as Iwatsu Bringo.
http://www.iti.iwatsu.co.jp/en/products/ds/bringo/bringo2_top_e.html (http://www.iti.iwatsu.co.jp/en/products/ds/bringo/bringo2_top_e.html)
https://www.eevblog.com/forum/testgear/the-most-weird-and-funny-dso-metrix-mtx3000/msg422131/#msg422131 (https://www.eevblog.com/forum/testgear/the-most-weird-and-funny-dso-metrix-mtx3000/msg422131/#msg422131)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Hydrawerk on September 02, 2015, 05:00:22 pm
More pictures. They were found on Ebay.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 02, 2015, 05:16:57 pm
More pictures. They were found on Ebay.

I know. They're from that joker that wants $679 for one:

http://www.ebay.com/itm/LeCroy-Literuner-LP142-DSO-100-MHz-500-MS-s-Digital-Oscilloscope-/290764290670?hash=item43b2e6fa6e (http://www.ebay.com/itm/LeCroy-Literuner-LP142-DSO-100-MHz-500-MS-s-Digital-Oscilloscope-/290764290670?hash=item43b2e6fa6e)

 :-DD
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Hydrawerk on September 02, 2015, 06:35:22 pm
In May 2000 it was a nice scope with quite long 100kpoints memory.
TDS2000 series with a color LCD was released later in 2002. https://web.archive.org/web/20020807225311fw_/http://www.tek.com/Measurement/cgi-bin/framed.pl?Document=/Measurement/scopes/index/prodindex_realtime.html&FrameSet=oscilloscopes (https://web.archive.org/web/20020807225311fw_/http://www.tek.com/Measurement/cgi-bin/framed.pl?Document=/Measurement/scopes/index/prodindex_realtime.html&FrameSet=oscilloscopes)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Len on September 02, 2015, 07:03:20 pm
Why in the world would they use TO-220 solder pin-mount heatsinks glued to those Altera FPGAs? That seems very odd. There are off-the-shelf little heatsinks for literally any package, available by the thousands. Why would they substitute a proper heatsink with what seems like either an afterthought or an emergency bodge?

It is a proper heat sink. The mounting pin sticking out the side doesn't hurt anyone (well, apparently it does, but I don't see why). Perhaps they already have that part in stock because they use it elsewhere, and they just didn't want to bother sourcing another part that's almost exactly the same. (Ask Dave about purchasing managers.)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 02, 2015, 07:27:43 pm
In May 2000 it was a nice scope with quite long 100kpoints memory.
TDS2000 series with a color LCD was released later in 2002. https://web.archive.org/web/20020807225311fw_/http://www.tek.com/Measurement/cgi-bin/framed.pl?Document=/Measurement/scopes/index/prodindex_realtime.html&FrameSet=oscilloscopes (https://web.archive.org/web/20020807225311fw_/http://www.tek.com/Measurement/cgi-bin/framed.pl?Document=/Measurement/scopes/index/prodindex_realtime.html&FrameSet=oscilloscopes)

The problem with the LiteRunner weren't its specs but its price, and at those days Tek's name had an even larger pull thanks to their analog scopes.

Plus there was HP/Agilent with the 54600 Series.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: dentaku on September 02, 2015, 08:45:58 pm
Hmmm .....  :popcorn:

(https://www.eevblog.com/forum/blog/eevblog-790-lecroy-wavejet-354-touch-oscilloscope-teardown/?action=dlattach;attach=168880;image)

It looks like it's part of the rubber case you can see even better at 37:48.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Dave on September 03, 2015, 05:40:20 am
Incredible boot time. You don't see that too often. :-+
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Kean on September 03, 2015, 07:34:33 am
Incredible boot time. You don't see that too often. :-+

It seemed very fast.  It actually had me wondering if Dave edited it out.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: EEVblog on September 03, 2015, 08:00:11 am
It seemed very fast.  It actually had me wondering if Dave edited it out.

Nope, it's that quick. Rare in todays world. Clearly not running embedded Windows or Linux.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 03, 2015, 08:47:51 am
Nope, it's that quick. Rare in todays world. Clearly not running embedded Windows or Linux.

The WaveJet runs VxWorks.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: AF6LJ on September 03, 2015, 06:13:50 pm
Good video; not my cup of tea; I think a touch screen on a piece of test equipment is not ergonomic.
Sure is built nice, that's for sure.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Hydrawerk on September 03, 2015, 07:15:26 pm
Those three PCBs in the scope look like there is a low level of integration. Well, most scopes (TDS2000, DPO2000, Rigol DS2000, Keysight DSOX2000... ) consist of just one big board with both analog and digital part.  This WaveJet scope looks a bit obsolete. I wonder if the touchscreen operation is effective or it just allowed the context buttons to disappear. One good news, the rear aux BNC can be configured asTrigger Output so we can measure the waveform update rate.  :-+
500MHz scope with 1GS/s in those days... well, for the price it is OK, but most 500MHz scopes have at least 2GS/s nowadays.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 03, 2015, 08:54:47 pm
Having said that, it's probably either TRON or QNX.

TRON is mostly used in cars and consumer appliances, as is QNX. Neither of them have found much use in test instruments.

As to the WaveJet, as I stated before it runs VxWorks, as do the other DSOs made by Iwatsu since the late '90s, and all the scopes that came out of the Iwatsu/LeCroy partnership.

Even Yokogawa scopes are based on VxWorks.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Laertes on September 03, 2015, 09:15:57 pm
WARNING: Rant that borders on offtopic

I never seem to understand the lower end scope market(like < EUR 10k)... maybe I'm too young and haven't seen as many series in that area come and go(actually, I only ever saw them come, they're all still around now ;D)
From my perspective, the Rigol DS4054 and the WaveJet 354T are pretty much exactly in the same spot in the market, so let's compare them:
[li]The Rigol doesn't have a touchscreen(IMO also minor, but still...)
[/li][/list]
In this list, in my view(does anyone disagree?), the DS4054 comes off much better, because while they are very similar, more memory is always a massive advantage and a higher sample rate seems to me like an advantage as well...
The Rigol has been around since 2012 IIRC, which is much shorter than the WaveJet 300 series has, but they released a new model with some additions(touchscreen...) now, so they're not just continuing to sell the thing until their part stocks run out and they can finally drop it without losing any money...

So, I wonder: Why in the world do LeCroy even release this thing now? Who would buy it, and why? Because of a touchscreen? Don't get me wrong, I love LeCroys touch scopes(I have a HDO4000 at my desk at work and it's the best scope to work with, UI wise, I have ever seen) but for a rather mid-pricy scope wouldn't the extra performance massively outweigh that?
Why didn't LeCroy choose to upgrade their tech a bit to modern day, you know, with some faster sampling with a non-obsolete ADC and maybe some more RAM in DDR3 form if they actually wanted to compete in that market?

And then there's the "Agilent or Keysight or whatever their bloody name is now"™(Trademark of Dave Jones, apparently) scopes - I mean, yeah, they're super duper fast and responsive and that has it's applications, but have you seen what they charge for 500Mhz,4ch, 2/4GS/S scope? We're beyond 10k there, and they have 2Mpts sample memory per channel for that price.

So, if you read through this, maybe you can help me figure out what made LeCroy tick here? What's their advantage over Rigol/how well are these things going to sell? And why do people pay twice as much for an "Agilent or Keysight or whatever their bloody name is now"? Are the update rates really worth that much?
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Bud on September 03, 2015, 11:31:43 pm
@Laertes

A short answer to your rigol vs anythingelse comparison is that rigol is not a properly designed product. Their oscilloscopes hardware is nothing more then snippets of reference designs from IC datasheets slapped together, and even with that they are not able to program the hardware correctly because they do not understand RF electronics. Rigol scopes are same crap as any other consumer product produced in China, just put in an eye candy box and sold at a affordable price. Now sit back, relax and ask yourself a question: why is it that the price is so low. There must be a reason for it.

As to your 4Gs vs 2Gs example, you need first to understand how rigol does it, and they do it by interleaving the input to multiple physical ADCs, which requires extreme care and expertise to design the board and write code to control it to ensure proper phase relationships and stitching of the interleaved signals. Perhaps anyone else beside rigol do understand the challenges of implementing this architecture and decided not to spoil their names making poorly performing products.


Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Bud on September 03, 2015, 11:39:56 pm
In regards to the 354's input stage in the video, it looked very similar to rigol 2072a input stage. The relays are a 50 Ohm input termination and a two-stage attenuator. I do not expect anything under the attenuator on the other side of the PCB. What may be after the attenuator stage is a high impedance buffer, unless it is on the top side of the PCB and I missed it in the video. With LMH6518 gain controlled amplifier just there is not much to put around it. And it is a pretty noisy beast, I was disappointed to see it in this scope front end.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: AF6LJ on September 04, 2015, 12:28:25 am
@Laertes

A short answer to your rigol vs anythingelse comparison is that rigol is not a properly designed product. Their oscilloscopes hardware is nothing more then snippets of reference designs from IC datasheets slapped together, and even with that they are not able to program the hardware correctly because they do not understand RF electronics. Rigol scopes are same crap as any other consumer product produced in China, just put in an eye candy box and sold at a affordable price. Now sit back, relax and ask yourself a question: why is it that the price is so low. There must be a reason for it.

As to your 4Gs vs 2Gs example, you need first to understand how rigol does it, and they do it by interleaving the input to multiple physical ADCs, which requires extreme care and expertise to design the board and write code to control it to ensure proper phase relationships and stitching of the interleaved signals. Perhaps anyone else beside rigol do understand the challenges of implementing this architecture and decided not to spoil their names making poorly performing products.
Nice way to explain the creepy feeling I get regarding their products.
The Spectrum analyzer / tracking generator issues expressed here in one thread have made me very weary of their gear.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 04, 2015, 05:35:59 am
I never seem to understand the lower end scope market(like < EUR 10k)... maybe I'm too young and haven't seen as many series in that area come and go(actually, I only ever saw them come, they're all still around now ;D)
From my perspective, the Rigol DS4054 and the WaveJet 354T are pretty much exactly in the same spot in the market, so let's compare them:
  • They both cost about EUR 5k without any options (354T is USD 5k on DigiKey, DS4054 is 4954 Euros on Batronix(rigol distirbutor in Germany))
  • They both have 500MHz input bandwith
  • Their Trigger, Math, Replay etc. functions appear very similar to me(though I have not used the 354T, so I don't know it's capabilities that well)
  • They both allow for similar waveform capture rates
  • The DS4054 has 140Mpts memory, which is 28 friggin times as much as the LeCroy(or, at least still 7 times as much on all channels)
  • The Rigol will  allow you to sample one channel with 4GS/S, the 354T only 2GS/S
  • The Rigol has smart probe support beyond 10x/1x (minor, but still...)
  • The Rigol doesn't have a touchscreen(IMO also minor, but still...)

In this list, in my view(does anyone disagree?)

No, but that doesn't tell the whole story.

Quote
the DS4054 comes off much better, because while they are very similar, more memory is always a massive advantage and a higher sample rate seems to me like an advantage as well...

If you only look at spec sheets, then yes you're right, the Rigol looks much more attractive. However, what it doesn't show is that the Rigol DS4000 is overall a pretty poor scope which came on the market with (and still has!) many issues. Rigol's hardware is certainly good but their firmware is mostly crap, not just on the DS4000. Yes, they work on it to some extend and fix many problems through updates but allmost all their products are plagued by firmware issues (just look at the various Rigol threads in this forum).

Then there's support. Rigol offers 3 yrs warranty as does LeCroy but that's where the commonalities end. LeCroy fully supports its scopes for 7 years after end of production, and after that on a "best effort" basis (they still offer repairs the old LeCroy 9300 Series DSOs which stopped production in 1998!). And long as the scope is in the 7yr main support period you can extend or buy new manufacturer warranty so you're covered if there's a defect even though the scope is older. Rigol on the other hand doesn't even have a Service Manual that actually deserves that name for its products, and offer very basic support only which is pretty much hit and miss.

As to the specs themselves, all the memory the Rigol has looks nice on the spec sheet, however in reality it's not of much use due to the lack of search functions, plus the scope is slow, and can't even use the memory for things where it would make most sense like FFT (which on the Rigol uses some 4k points if I remember right, which is a bad joke for a scope of 2012).

I'd say Rigol devices are probably good enough for hobbyist use (and their DS1054z is a great beginner's scope at a very good price!), but I wouldn't want to have their kit in a professional setup. Ever.

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The Rigol has been around since 2012 IIRC, which is much shorter than the WaveJet 300 series has, but they released a new model with some additions(touchscreen...) now,

Really? I guess I missed that one (I know that Siglent has just come out with a new scope, the SDS2000X).

We'll see if this new Rigol scope is again plagued by firmware issues as everything else they brought to market. I hope not but I won't hold my breath.

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so they're not just continuing to sell the thing until their part stocks run out and they can finally drop it without losing any money...

Right, but even after being on the market for that long the DS4000 still suffers from problems, which is pretty telling as to what priority fixing the various has for Rigol. That's what the difference between a big brand like LeCroy and a B-brand like Rigol.

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So, I wonder: Why in the world do LeCroy even release this thing now? Who would buy it, and why? Because of a touchscreen? Don't get me wrong, I love LeCroys touch scopes(I have a HDO4000 at my desk at work and it's the best scope to work with, UI wise, I have ever seen) but for a rather mid-pricy scope wouldn't the extra performance massively outweigh that? Why didn't LeCroy choose to upgrade their tech a bit to modern day, you know, with some faster sampling with a non-obsolete ADC and maybe some more RAM in DDR3 form if they actually wanted to compete in that market?

They did, it's called WaveSurfer 3000 and costs around the same as the WaveJet:
http://teledynelecroy.com/oscilloscope/oscilloscopeseries.aspx?mseries=466 (http://teledynelecroy.com/oscilloscope/oscilloscopeseries.aspx?mseries=466)

KF5OBS did a review last year:
https://www.youtube.com/watch?v=cK6LwYyYWDo (https://www.youtube.com/watch?v=cK6LwYyYWDo)

The WaveJet remains in the portfolio simply because it has a lot of customers in some big industries, not hobbyists but usually larger corporations who need a small portable but reliable scope (i.e. the ones who used to buy scopes like the Tek TDS200). They are buying the WaveJet because it does the job reliably, with no hassle, day by day. That it's more expensive than a B-brand scope is of no relevance to them.

For anyone else however, the WaveJet is simply too expensive for its specs, but that's why the WaveSurfer is there.

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And then there's the "Agilent or Keysight or whatever their bloody name is now"™(Trademark of Dave Jones, apparently) scopes - I mean, yeah, they're super duper fast and responsive and that has it's applications, but have you seen what they charge for 500Mhz,4ch, 2/4GS/S scope? We're beyond 10k there, and they have 2Mpts sample memory per channel for that price.

Yes, Keysight charges a ridiculous amount of money for the bigger models of their entry-level scopes DSOX2k/DSOX3k(T) but they do it simply because they get away with it.

People buy them because they carry the Keysight (ex-Agilent ex-ex-HP) name, and also because the other brand that world & dog associates with scopes (Tektronix) mostly produces average DSOs at best while essentially charging the same. it's the same reason why on ebay even the worst pile of old crap often fetches ridiculous bids as long as it says "Agilent" or "Tek" on the label.

LeCroy's problem is that unlike you're working with high end scopes or in high energy physics many people don't know them, or don't consider them for a cheaper scope because they believe LeCroy only makes high end scopes. Even many engineers know not muchg except Agilent/Keysight and Tektronix, even though LeCroy are pretty much pioneers of digital scopes and leading the pack with their technology (they also had the first >1M wfms/s scope in 2006, long before Agilent turned wafeform rates into a marketing hype). They also don't scream as loud as Keysight and Tek, which engage in noisy marketing with the silly 'ours-vs-theirs' "comparisons" and half-true marketing whitepapers

Also, many people assume that LeCroy is expensive, when in fact they're regularly cheaper than a comparable (or even inferior!) Keysight scope. For example, the WaveSurfer 3000 is pretty much cheaper than the DSOX3kT, plus for the price of a 500MHz 5GSa/s 4Mpts DSOX3054T you can already get a 1GHz 10Mpts 10GSa/s LeCroy WaveSurfer 10.

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So, if you read through this, maybe you can help me figure out what made LeCroy tick here? What's their advantage over Rigol/how well are these things going to sell?

The WaveJet isn't made for the same target audience as the DS4000 (hobbyists)and the customers who buy a WaveJet are unlikely to ever touch anything from a B-brand like Rigol. So comparing them is worthless.

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And why do people pay twice as much for an "Agilent or Keysight or whatever their bloody name is now"? Are the update rates really worth that much?

No, they aren't. The waveform rates are used by Keysight because that's essentially the only area where their entry level scopes can shine. As you said the sample memory is ridiculously small (thanks to limitations of their MegaZoom ASIC). But Keysight (despite the silly name change) has a good reputation (mostly deserved, as their kit is generally very good), plus they provide very good support. In addition, they offer everything from scopes to RF generators, spectrum analyzers, DVMs to more exotic kit (which is often an advantage when dealing with large companies who rather buy from a single source).

But in terms of performance, if you look at what else is out there more often than not the better performing and/or cheaper instrument comes from someone else than Agilent/Keysight (i.e. for spectrum analyzers and RF generators I'd definitely look at R&S).

However, many people are lazy, and only look at Keysight when shopping for gear, which means Keysight can essentially fleece them as they please. And frankly, I'd say they fully deserve to pay for their laziness.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Fungus on September 04, 2015, 08:42:33 am
As to your 4Gs vs 2Gs example, you need first to understand how rigol does it, and they do it by interleaving the input to multiple physical ADCs, which requires extreme care and expertise to design the board and write code to control it to ensure proper phase relationships and stitching of the interleaved signals. Perhaps anyone else beside rigol do understand the challenges of implementing this architecture and decided not to spoil their names making poorly performing products.

You can demonstrate these phase errors and stitching problems with actual signals and screenshots, right...?
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Hydrawerk on September 04, 2015, 03:40:12 pm
According to the manual, there is no serial decoding (SPI, I2C, UART) and no event search on WaveJet 354T.  :--
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Bud on September 04, 2015, 04:23:39 pm
You can demonstrate these phase errors and stitching problems with actual signals and screenshots, right...?
I can and I will demonstrate a few fundamental design errors in their DS2072a scope, without fixing which first it does not make sense to talk about anything else because no controlled conditions can be established for such testing. Furthermore, after viewing teardown videos of other rigol scopes I see a very good chance all of them may have the same errors copied over and over again.

What those design errors (or to be better described, incompetencies) are ? Hold your breath and wait for "Project Yaigol" post to be published. Information was collected months ago and being busy at full time work I do not know when it will see the light, but it eventually will.

EDIT: to avoid any confusion: this post was about rigol scopes, not LeCroy Wavejet
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Laertes on September 04, 2015, 06:20:59 pm
First of all, thank you guys for the answers.


@Laertes

A short answer to your rigol vs anythingelse comparison is that rigol is not a properly designed product. Their oscilloscopes hardware is nothing more then snippets of reference designs from IC datasheets slapped together

You say that, yet right after, you say
Quote
In regards to the 354's input stage in the video, it looked very similar to rigol 2072a input stage.
So, Rigol don't design their analog section properly, but LeCroy or Iwatsu aren't any better? I think that does
Also, while I'm no RF guy, I know that many times and especially for popular high-end chips(think precision voltage references) the reference design in the datasheet is simply the best way to go... and with purpo
And in relation I fully agree with this:
You can demonstrate these phase errors and stitching problems with actual signals and screenshots, right...?
Wonder if Dave or Shariar have anything on that? I think they both have the DS4000 Scopes...
I can and I will demonstrate a few fundamental design errors in their DS2072a scope, without fixing which first it does not make sense to talk about anything else because no controlled conditions can be established for such testing. Furthermore, after viewing teardown videos of other rigol scopes I see a very good chance all of them may have the same errors copied over and over again.

What those design errors (or to be better described, incompetencies) are ? Hold your breath and wait for "Project Yaigol" post to be published. Information was collected months ago and being busy at full time work I do not know when it will see the light, but it eventually will.
That I will watch out for.
Independent of the issues you may or may not uncover in that scope, I think your(and many other's) weariness of Rigol show that there is a general mistrust against chinese equipment in the industry(or in parts of it, anyway) that, funded or not, in part explains why people like LeCroy and Keysight can ask the prices they do...

Also, while I know that Rigol have firmware issues in their scopes and I also agree that these exist largely because they don't test properly to reduce cost, LeCroy have firmware bugs just as well... starting with simple things like the WaveJet 332 we have at work sometimes not increasing the voltage range from lowest with the first encoder rotation(it's spurious and not a big deal) and ranging to the Windows 7(seriously, why Windows?) running on the HDO4000 crashing and forcing you to wait for 3 mins while the damned thing reboots. I'm not certain that's enough...

Then there's support. Rigol offers 3 yrs warranty as does LeCroy but that's where the commonalities end. LeCroy fully supports its scopes for 7 years after end of production, and after that on a "best effort" basis (they still offer repairs the old LeCroy 9300 Series DSOs which stopped production in 1998!). And long as the scope is in the 7yr main support period you can extend or buy new manufacturer warranty so you're covered if there's a defect even though the scope is older. Rigol on the other hand doesn't even have a Service Manual that actually deserves that name for its products, and offer very basic support only which is pretty much hit and miss.
A topic I didn't think about at all. In hindsight, I completely agree with you, big plus for LeCroy(or Keysight, I have no experience with Tek but I assume they're on par). Come to think of it, that would probably be a dealbreaker for many companies.

Really? I guess I missed that one (I know that Siglent has just come out with a new scope, the SDS2000X).

We'll see if this new Rigol scope is again plagued by firmware issues as everything else they brought to market. I hope not but I won't hold my breath.
Sorry, misunderstanding. With they, I meant LeCroy. The WaveJet is largely unchanged since a long time, and yet they still added in a little gimmick with the touchscreen instead of just phasing it out...


They did, it's called WaveSurfer 3000 and costs around the same as the WaveJet:
Well, they are USD2000 more for the same number of channels/same bandwith(though better additional features, of course, like the large screen that is just awesome)

LeCroy's problem is that unlike you're working with high end scopes or in high energy physics many people don't know them, or don't consider them for a cheaper scope because they believe LeCroy only makes high end scopes.
Hmmm...that is not my experience. As a matter of fact, I have never worked at a place that didn't own LeCroy scopes or that didn't consider them at all. Of course, LeCroy does seem to specifically target more niche markets with stuff like offering rare or obscure decoders like Arinc429 and I do Avionics, so that might explain that.


Even many engineers know not muchg except Agilent/Keysight and Tektronix
the customers who buy a WaveJet are unlikely to ever touch anything from a B-brand like Rigol. So comparing them is worthless.
That's what I really don't like... Engineers with that small a horizon? Why wouldn't you consider LeCroy(whose portfolio in your specific market you would find if you googled for scopes) or Rigol? Like when you're going to make a proper investment and buy something for $5k and up, wouldn't you generally spend at least an hour considering which one to get? If you did, you might want to find the lack of support and firmware issues to rule out Rigol, but not LeCroy vs. Keysight or Tek...
And if you just need a scope for those little tasks that in the end turn out to take you 75% of your time, where you don't need fancy sample rates, or four channels because you're just checking in what order your supplies are turning on or wether or not your SPI clock is set to the right frequency, why not get a cheap rigol and buy a new one everytime you have an issue with it instead of hoping for support...


In summary, I think my question has been answered pretty well: Spec sheet features don't mean everything, Support is a big deal to businesses, a history of trust or mistrust is very important and sometimes, the issue lies in the laziness.

 
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Chipguy on September 05, 2015, 01:36:35 pm
Had a look on similar Iwatsu scopes. That unpopulated connector seems to be a "Port for future expansion".
http://www.iti.iwatsu.co.jp/en/pdf/ds-5500_e.pdf (http://www.iti.iwatsu.co.jp/en/pdf/ds-5500_e.pdf)
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Hydrawerk on September 05, 2015, 10:38:58 pm
I would miss a VGA or DVI output on Wavejet scopes. There is even no plug-in module possibility.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: EEVblog on September 05, 2015, 11:56:44 pm
the customers who buy a WaveJet are unlikely to ever touch anything from a B-brand like Rigol. So comparing them is worthless.
That's what I really don't like... Engineers with that small a horizon? Why wouldn't you consider LeCroy(whose portfolio in your specific market you would find if you googled for scopes) or Rigol? Like when you're going to make a proper investment and buy something for $5k and up, wouldn't you generally spend at least an hour considering which one to get?

Actually, a lot of people don't. Why? Because they have been using X brand for decades and their gear has earned their trust for various reasons, so they just buy X brand again. It's a safe bet thing.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: EEVblog on September 06, 2015, 12:15:12 am
Yes, Keysight charges a ridiculous amount of money for the bigger models of their entry-level scopes DSOX2k/DSOX3k(T) but they do it simply because they get away with it.

It's not just that, it's because it's a damn good scope.
Remember, the Keysiht X series is now 4 1/2 years old and is still the fastest updating and most responsive scope on the market with a crazy array of advanced analysis options. e.g. the power measurement analysis stuff.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 06, 2015, 08:19:44 am
Independent of the issues you may or may not uncover in that scope, I think your(and many other's) weariness of Rigol show that there is a general mistrust against chinese equipment in the industry(or in parts of it, anyway) that, funded or not, in part explains why people like LeCroy and Keysight can ask the prices they do...

Not really. Trust may have some part but the reality is that they produce (with exceptions) vastly better kit than the Chinese B-brands. Plus the big names offer much more than simple entry level scopes, stuff that is simply out of reach for the Chinese manufacturers.

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Also, while I know that Rigol have firmware issues in their scopes and I also agree that these exist largely because they don't test properly to reduce cost

It's not just because they don't test well. Most kit from Chinese B-brands is plagued by software problems, Rigol is not an exception but the rule (and also one of the better ones, i.e. Siglent is even worse!). The biggest problem is that they don't seem to understand that the software is at least as important as the hardware, and requires proper development processes. Instead, Chinese B-brands tend to focus on the hardware (which in case of Rigol and Siglent is pretty good) while software is still treated as an afterthought.

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LeCroy have firmware bugs just as well... starting with simple things like the WaveJet 332 we have at work sometimes not increasing the voltage range from lowest with the first encoder rotation(it's spurious and not a big deal) and ranging to the Windows 7(seriously, why Windows?) running on the HDO4000 crashing and forcing you to wait for 3 mins while the damned thing reboots.

How do you know it's a firmware bug? The WaveJet problem sounds like a hardware defect (if it's the non-A version in the white case then it may well be that the decoder is worn out and needs replacing, which isn't difficult to do), as does the HDO4000 problem as this definitely isn't normal. The HDO Series had some minor issues when they came out but that has long been fixed with a firmware update.

And the main reason to run Windows on a scope is that you can run other applications (i.e. Mathlab) on it, which especially with the XDEV options available for many LeCroy scopes is great as you can write your own software that has full access to the raw data stream of the DSO. The only downside of a Windows scope is the longer boot time, but in a serious lab where kit isn't just powered up to do some quick tests and then powered off but runs essentially all day that's essentially a non-issue, especially since every scope requires a warm-up period during which its specs aren't guranteed and during which measurements are unreliable. In my experience (and I'm mostly using high end scopes in my work which are all Windows based) they're as rock solid as non-Windows scopes, and only become unstable if there's a real problem (usually hardware).

In addition, there's a huge difference between a bug that causes the device to crash/freeze/whatever and a bug that produces untrustworthy data, the latter of which Rigol and Siglent have seen quite a bit with their firmware problems.

[Support]

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A topic I didn't think about at all. In hindsight, I completely agree with you, big plus for LeCroy(or Keysight, I have no experience with Tek but I assume they're on par). Come to think of it, that would probably be a dealbreaker for many companies.

Not just for companies, at least for me it's also a dealbreaker for the stuff I have in my home lab.

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Sorry, misunderstanding. With they, I meant LeCroy. The WaveJet is largely unchanged since a long time, and yet they still added in a little gimmick with the touchscreen instead of just phasing it out...

Why remove a product that still sells well enough and has earned itself a great reputation amongst its customers?

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They did, it's called WaveSurfer 3000 and costs around the same as the WaveJet:
Well, they are USD2000 more for the same number of channels/same bandwith

Yes, if you pay list price or buy from resellers. However, LeCroy is pretty keen to get a bigger foothold in the low end scope market, and therefore wants to get the WaveSurfer 3000 out there. There often are very good deals available with the WS3k (while there isn't much for the WaveJet!), and if you talk directly with LeCroy there's a good chance you can get a WS3054 for the same price as a WaveJet 354T.

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LeCroy's problem is that unlike you're working with high end scopes or in high energy physics many people don't know them, or don't consider them for a cheaper scope because they believe LeCroy only makes high end scopes.

Hmmm...that is not my experience. As a matter of fact, I have never worked at a place that didn't own LeCroy scopes or that didn't consider them at all. Of course, LeCroy does seem to specifically target more niche markets with stuff like offering rare or obscure decoders like Arinc429 and I do Avionics, so that might explain that.

It doesn't. I work in a similar field (although I mostly need MIL-1553 while I rarely touch ARINC429), and when I still worked in Germany (which admittedly has now been a little while ago) the majority of scopes in that field where Agilent and Tek, with LeCroy mostly limited to the high end (i.e. WaveRunner and up). They seem to be even less common here in the UK (probably because Agilent had manufacturing over here), and only when I work in the States I'll see them in larger numbers.

Also, both standards (ARINC429 and MIL-1553) are pretty common amongst the options found on Agilent/Keysight and Tek scopes, aside from the very bottom end models. Even the low-end DSOX3k(T) can optionally decode ARINC429 and MIL-1553 (the Tek MDO3k seems to only do MIL-1553, as did older Agilent DSO7k Series). Most of the larger models can decode ARINC429 as well. Plus, the DSOX3k(T) is probably the cheapest scope that can decode ARINC429 (LeCroy's cheapest scope to do that is the WaveSurfer 10 which is $10k and only cheaper when compared with the larger DSOX3kT models; however, for ARINC429 even the 100MHz 2Ch variant of the DSOX3(T) would suffice).

The areas where LeCroy really shines is stuff like hard disk analysis, signal analysis, math, or for looking at modern highly complex high speed stuff like 10GE, DDR3, Fibre Channel and so on. Or Power Analysis on the truly 12bit HDO Series.

the customers who buy a WaveJet are unlikely to ever touch anything from a B-brand like Rigol. So comparing them is worthless.
That's what I really don't like... Engineers with that small a horizon? Why wouldn't you consider LeCroy(whose portfolio in your specific market you would find if you googled for scopes) or Rigol? Like when you're going to make a proper investment and buy something for $5k and up, wouldn't you generally spend at least an hour considering which one to get? If you did, you might want to find the lack of support and firmware issues to rule out Rigol, but not LeCroy vs. Keysight or Tek...[/quote]

That hasn't much to do with engineers having a limited horizon, especially not in a business environment. As long as the Keysight instrument does the job and doesn't exceed the budget there's not much use to shop around to save maybe $500 or even $1000, especially when the lab has never worked with kit from the other manufacturer and doesn't really know how their gear behaves in reality. If there's time you can just ask for loaners/demo units and test them out in the target environment, but that luxury isn't available every time, so businesses buy the instrument from the manufacturer they know. And simply because Agilent has the largest portfolio the chance is high that Agilent/Keysight is what they'll choose.

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And if you just need a scope for those little tasks that in the end turn out to take you 75% of your time, where you don't need fancy sample rates, or four channels because you're just checking in what order your supplies are turning on or wether or not your SPI clock is set to the right frequency, why not get a cheap rigol and buy a new one everytime you have an issue with it instead of hoping for support...

So how does buying another Rigol scope fix the inherent firmware issue you just lost several hours on? Exactly, it doesn't. Plus even that single incident meant you lost valuable time that could have earned you much more than the price difference between a B-brand like Rigol and a big brand like LeCroy, Keysight or even R&S (which is pretty expensive, even for a big brand).

I appreciate that for a hobbyist the purchase price of a scope is often a big investment, however in a commercial environment $5k are often pocket change compared with the money that is involved. The $5k WaveJet might very well be used by an engineer with a charge out rate of $300 or more who could easily work on stuff which earns the company in excess of $1k (as it's the case in some industries). The price difference between a WaveJet and a Rigol isn't even worth considering, especially when that means moving from a manufacturer with a rock-solid, proven product to a cheap B-brand with a bag of firmware problems, a gamble which easily could result in the business losing money, losing customers and get you fired.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 06, 2015, 11:45:50 am
Yes, Keysight charges a ridiculous amount of money for the bigger models of their entry-level scopes DSOX2k/DSOX3k(T) but they do it simply because they get away with it.

It's not just that, it's because it's a damn good scope.
Remember, the Keysiht X series is now 4 1/2 years old and is still the fastest updating and most responsive scope on the market with a crazy array of advanced analysis options. e.g. the power measurement analysis stuff.

If it was still 2012 then I'd agree. But not in 2015. Yes, the waveform rate is still the highest in its class, but that's essentially it. In 2015, for a scope in the price class of the DSOX3k(T) the 4M sample memory is very small, and looks even more silly for the higher bandwidth models like the DSOX3054T which costs in excess of $10k. And I'd argue that in practice having a larger sample memory (which allows you to sample at higher sample rates at longer timebase settings or record longer sequences) is a much bigger real-life advantage than an excessive waveform rate (which it will reach in specific settings only anyways), especially when the larger memory is also coupled with versatile analysis tools (which the DSOX doesn't have). In addition, even with 4M sample memory the DSOX3kT only uses a measly 64kpts for FFT (very likely because that's the limit the slow architecture can cope with). Plus the DSOX is pretty much a full-auto scope with many settings that can't be changed like sample memory depth or interpolation, which isn't exactly an advantage.

I agree that the available options for the DSO3k(T) are nice, however many like UART and CAN are also available for the (much cheaper) WaveSurfer 3000. Others like power measurements aren't very useful on a low bandwidth scope, for which you'd probably look at the 500Mhz 4Ch variant of the DSOX3kT which is in a price bracket that already offers more advanced scopes like the WaveSurfer 10 (which for less money than a DSOX3054T offers double the bandwidth (1GHz), double the sample rates (10GSa/s) and 4x the sample memory (16Mpts), plus the analysis tools are a lot better than anything that's available on the DSOX Series).

I'm not saying the DSOX3k(T) is a bad scope, all I'm saying is that it's no longer the best scope in it class as it was in 2012, and considering the alternatives that are available today the DSOX3k(T) is pretty much overpriced for what it brings to the table.

Agilent/Keysight has clearly painted themselves into a corner with their MegaZoom ASIC, a corner where it will be difficult for them to come out of.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Laertes on September 07, 2015, 06:37:41 pm
How do you know it's a firmware bug? The WaveJet problem sounds like a hardware defect (if it's the non-A version in the white case then it may well be that the decoder is worn out and needs replacing, which isn't difficult to do), as does the HDO4000 problem as this definitely isn't normal. The HDO Series had some minor issues when they came out but that has long been fixed with a firmware update.
The WaveJet issue only happens when the scope is in lowest voltage range, not in the others. As far as I can tell, it also only happens when both channels are on. It is not a hardware issue.

As for the HDO4000... I'm honestly not sure, can you update the firmware via USB Stick? I know for sure the FW has never been updated since it was bought, so it might still have bugs from early releases. I can't hook the scope up to the internet, thanks to our IT department(though I honestly have strong scruples hooking a >$10k machine with completely unprotected Windows on it to the internet, but for just a quick update I probably wouldn't mind).

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And the main reason to run Windows on a scope is that you can run other applications (i.e. Mathlab) on it
Do people use this feature? I can't imagine a reason to, not when I have a dozen computers right next to it, with much more power and much more convenient UIs...
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especially with the XDEV options available for many LeCroy scopes is great as you can write your own software that has full access to the raw data stream of the DSO.
THAT I can get behind, especially for more specific applications(maybe stuff like using your scope for a quick Test Jig that is more complicated than simple masking or something).
But you could just as well do that with VxWorks or even Linux or anything that is more reputable than Windows. Then again, scopes don't need to be able to run 24/7 for five years straight or anything like that, so the serious stability issues that you might experience on Windows will probably not have any effect at all. Wonder if it is easier to port Windows to the scope rather than Linux or VxWorks. Also, I wonder how the choice of operating several platforms(someone stated the WaveJet ran VxWorks, right?) came about...

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In addition, there's a huge difference between a bug that causes the device to crash/freeze/whatever and a bug that produces untrustworthy data, the latter of which Rigol and Siglent have seen quite a bit with their firmware problems.
I agree. Rigol's firmware is much worse than that of LeCroy or Keysight, there's no doubting that. I merely wanted to state that I feel that sometimes, people are a little bit harsh on the issues Rigol has/blow them out of proportion. The problems that cause wrong waveforms are of course absolutely not acceptable, but so far the only one I have seen is the one Dave showed in one of his videos with the AC trigger issue. I don't know if that exists on the somewhat advanced expensive Rigol 4000...

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Why remove a product that still sells well enough and has earned itself a great reputation amongst its customers?
Why spend money "improving" a scope that still sells well with something that hardly adds any value(or is that another misconception of mine? does the touchscreen add significant value in your eyes?)
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Yes, if you pay list price or buy from resellers. However, LeCroy is pretty keen to get a bigger foothold in the low end scope market, and therefore wants to get the WaveSurfer 3000 out there. There often are very good deals available with the WS3k (while there isn't much for the WaveJet!), and if you talk directly with LeCroy there's a good chance you can get a WS3054 for the same price as a WaveJet 354T.
I did not know that. Will remember it, though, for the next investment - go talk to LeCroy...

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It doesn't. I work in a similar field (although I mostly need MIL-1553 while I rarely touch ARINC429), and when I still worked in Germany (which admittedly has now been a little while ago) the majority of scopes in that field where Agilent and Tek, with LeCroy mostly limited to the high end (i.e. WaveRunner and up). They seem to be even less common here in the UK (probably because Agilent had manufacturing over here), and only when I work in the States I'll see them in larger numbers.
Interesting how our experiences differ in that respect. I worked optical semiconductor testing before getting into avionics and they had some really high end LeCroy gear. But in the Avionics market I have seen the low-end stuff quite often. Maybe their campaing to get into the lower end market is already paying off?

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Also, both standards (ARINC429 and MIL-1553) are pretty common amongst the options found on Agilent/Keysight and Tek scopes, aside from the very bottom end models. Even the low-end DSOX3k(T) can optionally decode ARINC429 and MIL-1553 (the Tek MDO3k seems to only do MIL-1553, as did older Agilent DSO7k Series). Most of the larger models can decode ARINC429 as well. Plus, the DSOX3k(T) is probably the cheapest scope that can decode ARINC429 (LeCroy's cheapest scope to do that is the WaveSurfer 10 which is $10k and only cheaper when compared with the larger DSOX3kT models; however, for ARINC429 even the 100MHz 2Ch variant of the DSOX3(T) would suffice).
A half-well trained HAM radio operator with a little morse knowledge and a speaker would suffice to decode A429 ;)
Forcing those who need it to buy bigger scopes earns you more money, though...

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So how does buying another Rigol scope fix the inherent firmware issue you just lost several hours on? Exactly, it doesn't. Plus even that single incident meant you lost valuable time that could have earned you much more than the price difference between a B-brand like Rigol and a big brand like LeCroy, Keysight or even R&S (which is pretty expensive, even for a big brand).

I appreciate that for a hobbyist the purchase price of a scope is often a big investment, however in a commercial environment $5k are often pocket change compared with the money that is involved. The $5k WaveJet might very well be used by an engineer with a charge out rate of $300 or more who could easily work on stuff which earns the company in excess of $1k (as it's the case in some industries). The price difference between a WaveJet and a Rigol isn't even worth considering, especially when that means moving from a manufacturer with a rock-solid, proven product to a cheap B-brand with a bag of firmware problems, a gamble which easily could result in the business losing money, losing customers and get you fired.
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I still don't quite agree. I own Rigol in private and I have not ever spent even just an hour working around an issue on the scope to get my actual work done, and I have done a few projects similar in complexity to the ones I would at work. Of course, the question remains whether the benefits of switching toward cheaper stuff outweigh the risks and clearly, that is not the case for the engineers out there. So, my initial question is thoroughly answered.

Thank You!
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: Wuerstchenhund on September 08, 2015, 05:44:10 am
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How do you know it's a firmware bug? The WaveJet problem sounds like a hardware defect (if it's the non-A version in the white case then it may well be that the decoder is worn out and needs replacing, which isn't difficult to do), as does the HDO4000 problem as this definitely isn't normal. The HDO Series had some minor issues when they came out but that has long been fixed with a firmware update.
The WaveJet issue only happens when the scope is in lowest voltage range, not in the others. As far as I can tell, it also only happens when both channels are on. It is not a hardware issue.

Have you tried updating the firmware? Although it still could be a hardware defect.

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As for the HDO4000... I'm honestly not sure, can you update the firmware via USB Stick? I know for sure the FW has never been updated since it was bought, so it might still have bugs from early releases. I can't hook the scope up to the internet, thanks to our IT department(though I honestly have strong scruples hooking a >$10k machine with completely unprotected Windows on it to the internet, but for just a quick update I probably wouldn't mind).

You don't connect a scope to the open internet, Windows or not.

As for updating the HDO (or the WaveJet), just go to the LeCroy website, download the firmware update, put in on a USB stick and run the file on the scope. It's really worth updating at least somewhat regularly because aside from bug fixes these updates also often include various improvements or new functions. For example, the WS3k comes with a buil-in signal generator which can be enabled through a software option, and when it came out it could only generate standard waveforms (i.e. sine, square, triangle etc). A later firmware update turned it into a full arbitary waveform generator, plus all WS3k's got the DVM readout for free.

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And the main reason to run Windows on a scope is that you can run other applications (i.e. Mathlab) on it
Do people use this feature? I can't imagine a reason to, not when I have a dozen computers right next to it, with much more power and much more convenient UIs...

Yes, people use this - a lot, especially on high end scopes. A separate PC is worthless when you want to access raw sampling data in real-time, which you need to do on the scope itself.

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especially with the XDEV options available for many LeCroy scopes is great as you can write your own software that has full access to the raw data stream of the DSO.
THAT I can get behind, especially for more specific applications(maybe stuff like using your scope for a quick Test Jig that is more complicated than simple masking or something).
But you could just as well do that with VxWorks or even Linux or anything that is more reputable than Windows.

No, not really, at least not unless you reinvent the wheels. Like it or not, Windows is the platform with the by far largest amount of available software.

Also, it's no longer 1999 and we no longer run Windows 98 which admittedly wasn't the most reliable OS, and at least the Windows NT descendants (W2k, WinXP, Vista, W7, Win8/8.1, lets just leave Win10 out of it for now) are rock-solid unless the hardware they run on is shit or the user does something stupid.

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Then again, scopes don't need to be able to run 24/7 for five years straight or anything like that, so the serious stability issues that you might experience on Windows will probably not have any effect at all.

Again, there are no stability issues, unless you introduce some. But then the OS doesn't matter, as you can easily drive Linux or VxWorks against the wall as well.

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Wonder if it is easier to port Windows to the scope rather than Linux or VxWorks.


These days it is, especially when modern high end scopes contain a normal x86/x64 PC.

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Also, I wonder how the choice of operating several platforms(someone stated the WaveJet ran VxWorks, right?) came about...

Older scopes used embedded platforms (i.e. PowerPC for LeCroy scopes), and for those running WindowsNT didn't bring any benefits. Plus VxWorks required a lot less ressources, which in those days were much more limited.

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I agree. Rigol's firmware is much worse than that of LeCroy or Keysight, there's no doubting that. I merely wanted to state that I feel that sometimes, people are a little bit harsh on the issues Rigol has/blow them out of proportion. The problems that cause wrong waveforms are of course absolutely not acceptable, but so far the only one I have seen is the one Dave showed in one of his videos with the AC trigger issue. I don't know if that exists on the somewhat advanced expensive Rigol 4000...

At the end it up to you to say how much these issue matter, but for me they matter - a lot. I don't want that for my small home lab, and in the professional environment I work that simply is unacceptable. Plus the savings aren't worth it.

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Why remove a product that still sells well enough and has earned itself a great reputation amongst its customers?
Why spend money "improving" a scope that still sells well with something that hardly adds any value(or is that another misconception of mine? does the touchscreen add significant value in your eyes?)

For the same reason that Keysight gave the aging DSOX3k a similar facelift - to make a product more attractive and looking a bit more 'fresh' by adding stuff that at the end of the day doesn't cost them much money. And although the real-world value is certainly limited (especially of touch on these scopes) it also (and more importantly) conveys the message that the manufacturer does care about this product and its customers.


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Yes, if you pay list price or buy from resellers. However, LeCroy is pretty keen to get a bigger foothold in the low end scope market, and therefore wants to get the WaveSurfer 3000 out there. There often are very good deals available with the WS3k (while there isn't much for the WaveJet!), and if you talk directly with LeCroy there's a good chance you can get a WS3054 for the same price as a WaveJet 354T.
I did not know that. Will remember it, though, for the next investment - go talk to LeCroy...

However, don't forget that in general stuff in Germany is pretty expensive compared to many other countries, and while I found the US headquarters very helpful and prices (even for spare parts) pretty good, this wasn't necessarily equally true of European pricing. But at the end of the day if you're willing to haggle then it's very likely that you'll be offered a good deal, especially when you accidentally drop the name 'Keysight' in there

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It doesn't. I work in a similar field (although I mostly need MIL-1553 while I rarely touch ARINC429), and when I still worked in Germany (which admittedly has now been a little while ago) the majority of scopes in that field where Agilent and Tek, with LeCroy mostly limited to the high end (i.e. WaveRunner and up). They seem to be even less common here in the UK (probably because Agilent had manufacturing over here), and only when I work in the States I'll see them in larger numbers.
Interesting how our experiences differ in that respect. I worked optical semiconductor testing before getting into avionics and they had some really high end LeCroy gear.[/quote]

Ok, that's a bit different then (I thought you were talking about system design and integration, i.e. building Avionics kit and integrating it into aircraft). And yes, it's true, LeCroy is pretty common in the semiconductor industry in general. I've seen a lot of WavePros and WaveMaster there.

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But in the Avionics market I have seen the low-end stuff quite often. Maybe their campaing to get into the lower end market is already paying off?

Quite possible, although no low-end LeCroy supports either ARINC nor MIL-1553 (the smallest model scope that does is the WaveSurfer 10, which is a mid-range scope).

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A half-well trained HAM radio operator with a little morse knowledge and a speaker would suffice to decode A429 ;)
Forcing those who need it to buy bigger scopes earns you more money, though...

That's not the reason why LeCroy's low end scopes don't do ARINC/MIL-1553. Other than Agilent/Keysight who produce their own entry level scopes (DSOX2k/3k), LeCroy has no interest designing low end stuff, and therefore just buys their entire entry-level portfolio in. The WaveAce (Siglent SDS1000 rebadges) are primitive scopes that don't do any decoding. The WaveJet is bought-in, too, and Iwatsu doesn't see any benefit in adding ARINC/MIL-1553 decode. The WaveSurfer 3000 (which sits between entry level and lower mid-range) only came out a year ago, and while LeCroy produces the firmware for it (hardware is Siglent) and already has added more decoding capabilities (i.e. CAN) there doesn't seem to be enough demand for ARINC/MIL-1553 on the WS3k to justify the costs of adding it (although personally I'd really like to see MIL-1553 on that scope).
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: John Coloccia on September 10, 2015, 03:51:21 pm
Actually, a lot of people don't. Why? Because they have been using X brand for decades and their gear has earned their trust for various reasons, so they just buy X brand again. It's a safe bet thing.

Spot on. When selecting lab gear, the most important things to me are confidence and familiarity. I may even have lots and lots of code written to interact with a particular brand of equipment. The edges of the specs don't mean much to me.  If something is really on the edge, I just go one step up and I'm in my comfort zone again. It's different as a small business, as I am now, or as a hobbyist.  Then I'm very keen on things like optimizing cost and performance. At a larger company? If I spend a day exploring different scopes and trade offs, and honestly it would probably take more than one day to really figure it all out, how much does that cost? Engineers are expensive...$150 to $200 an hour billable is pretty common. Who's paying for that? It would be silly to spend $1500+ on overhead when I can just overspend a bit on a scope that will get amortized over 10 years or more of use.
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: LabSpokane on September 10, 2015, 04:50:59 pm
Actually, a lot of people don't. Why? Because they have been using X brand for decades and their gear has earned their trust for various reasons, so they just buy X brand again. It's a safe bet thing.

Spot on. When selecting lab gear, the most important things to me are confidence and familiarity. I may even have lots and lots of code written to interact with a particular brand of equipment. The edges of the specs don't mean much to me.  If something is really on the edge, I just go one step up and I'm in my comfort zone again. It's different as a small business, as I am now, or as a hobbyist.  Then I'm very keen on things like optimizing cost and performance. At a larger company? If I spend a day exploring different scopes and trade offs, and honestly it would probably take more than one day to really figure it all out, how much does that cost? Engineers are expensive...$150 to $200 an hour billable is pretty common. Who's paying for that? It would be silly to spend $1500+ on overhead when I can just overspend a bit on a scope that will get amortized over 10 years or more of use.

Exactly.  The above, plus when you do encounter a problem, the company you "overspent" on answers the phone.  Or even better, as has happened multiple times now to me, this "overpriced" company surfs EEVBlog forums and proactively contacts you when they spot a question.  Those people cost money, and I knowingly chose to pay for their services with my equipment purchase.  They're worth it, and I thank them.   :-+   
Title: Re: EEVblog #790 - Lecroy Wavejet 354 Touch Oscilloscope Teardown
Post by: f4eru on November 25, 2015, 12:17:00 pm
You saw the teardown, now look at the manufacturing :

https://www.youtube.com/watch?v=xUTD3Tku8UY#t=90 (https://www.youtube.com/watch?v=xUTD3Tku8UY#t=90)
WARNING : Windows Inside !!
Never Ever design a series product with windows! You've been warned. See the trouble they have to keep it virus free until they ship the unit :)