Forums

Best Oscilloscope for $3k

Started by ChesterW August 26, 2014
On 2014-08-26, rickman <gnuarm@gmail.com> wrote:

>> The fact that they claim to support XP through 8 is a good sign. You >> can probably count on getting updated drivers/software for 9 in a few >> years. After that, you may or may not get further software support. > > I have been wanting to switch to Linux for some time now but never made > the jump. I may be mistaken but I believe a Linux compatible device is > much less likely to be broken by new versions of the OS, no? I won't > buy a LogicPort from Intronix because they don't support Linux or Android.
if the drivers are open srouce then yes, else probably no. contrast 10 year old ATI and NVIDIA graphics cards. -- umop apisdn --- news://freenews.netfront.net/ - complaints: news@netfront.net ---
On Wednesday, August 27, 2014 10:43:46 AM UTC+2, rickman wrote:
> On 8/27/2014 4:35 AM, Klaus Kragelund wrote: >=20 > > On Wednesday, August 27, 2014 1:34:43 AM UTC+2, rickman wrote: >=20 > >> On 8/26/2014 7:26 PM, John Miles, KE5FX wrote: >=20 > >> >=20 > >>> On Tuesday, August 26, 2014 3:58:50 PM UTC-7, Tim Williams wrote: >=20 > >> >=20 > >>>> If you're looking at lower level Agilents, might as well go directly=
to
>=20 > >> >=20 > >>>> >=20 > >> >=20 > >>>> Rigol -- they're the same things, Agilent just rebrands them. Tek d=
oes
>=20 > >> >=20 > >>>> >=20 > >> >=20 > >>>> the same thing but with a different Chinese brand (but who would wan=
t a
>=20 > >> >=20 > >>>> >=20 > >> >=20 > >>>> Tek interface in this day and age, anyway?). The ones around $1-2k =
are
>=20 > >> >=20 > >>>> >=20 > >> >=20 > >>>> comparable, and you get more features per buck that way. >=20 > >> >=20 > >>>> >=20 > >> >=20 > >>>> Tim >=20 > >> >=20 > >>> >=20 > >> >=20 > >>> At the $3K level he will be (or should be) looking at an Agilent DSO2=
000-X or DSO3000-X series, or one of the lower-end DSO6000A series, not one= of the rebadged Rigols. He should buy a gently used one on eBay if necess= ary to meet the budget. It is worth it. Agilent has beaten everybody else= 's DSOs to a bloody pulp over the last few years.
>=20 > >> >=20 > >> >=20 > >> >=20 > >> I'm confused. Tim is saying Agilent and Rigol scopes are the same >=20 > >> >=20 > >> thing. Why do you say the OP should be looking at an Agilent scope? >=20 > >> >=20 > >> >=20 > >> >=20 > >> >=20 > >> >=20 > >>> Re: NeonJohn's comment, he's spot on. A USB oscilloscope is like a U=
SB handgun. (And I say this as a designer of USB test gear. Headless inst= rumentation can be great, but not for something as fundamental as an oscill= oscope or DMM.)
>=20 > >> >=20 > >> >=20 > >> >=20 > >> I can't agree with this. I have held off buying a new scope for some >=20 > >> >=20 > >> time now while I continue to look for a good inexpensive mixed signal >=20 > >> >=20 > >> USB headless scope. There are a couple of Hantek units I am consideri=
ng.
>=20 > >> >=20 > > I have a Picoscope for close to 10 years now, works flawlessly >=20 >=20 >=20 > Yeah, I've heard a lot of good things about the Picoscopes, but they are=
=20
>=20 > very pricey. I also don't recall them making a mixed signal scope, am I=
=20
>=20 > wrong? >=20 >=20
Go to http://www.picotech.com/oscilloscope.html They have 2 mixed signal scopes. You can download the software and run it without a scope. It will run a sam= ple waveform, so you can get the feeling for the controls and the features Cheers Klaus
On Tue, 26 Aug 2014 16:26:58 -0700 (PDT) "John Miles, KE5FX"
<jmiles@gmail.com> wrote in Message id:
<64737ae0-d54a-4a26-86a6-4833a0680951@googlegroups.com>:

>Re: Phil's comment, I like my 694C immensely, but every time I turn it on I have to wonder if this is the last day on the job for its trigger chip.
Hi John, Now that it has an LCD, you could always keep it running 24/7 if you suspect it happens on a power up, . :) I suspect that many of these scopes spent most of their lives turned on which is why there's so many of them with dim CRTs and loaded with dust inside. Were you ever able to fix or diagnose the other 694C you bought? Jay (Who sold you your working one...)
On 8/27/2014 5:39 AM, Klaus Kragelund wrote:
> On Wednesday, August 27, 2014 10:43:46 AM UTC+2, rickman wrote: >> On 8/27/2014 4:35 AM, Klaus Kragelund wrote: >> >>> On Wednesday, August 27, 2014 1:34:43 AM UTC+2, rickman wrote: >> >> >>> I have a Picoscope for close to 10 years now, works flawlessly >> >> >> >> Yeah, I've heard a lot of good things about the Picoscopes, but they are >> >> very pricey. I also don't recall them making a mixed signal scope, am I >> >> wrong? >> >> > Go to > > http://www.picotech.com/oscilloscope.html > > They have 2 mixed signal scopes. > > You can download the software and run it without a scope. It will run a sample waveform, so you can get the feeling for the controls and the features
Yes, they have MSOs, but they are still pricey. $1,700 for a model with 200 MHz bandwidth. Hantek doesn't have a similar model, their top bandwidth is 60 MHz for a MSO, but that unit is only $400. The Picoscope 60 MHz model is over $1000. -- Rick
On Tue, 26 Aug 2014 17:38:10 -0400, rickman <gnuarm@gmail.com> wrote:


>I have been wanting to switch to Linux for some time now but never made >the jump. I may be mistaken but I believe a Linux compatible device is >much less likely to be broken by new versions of the OS, no? I won't >buy a LogicPort from Intronix because they don't support Linux or Android.
Almost always correct. We became an all-Linux shop about 5 or 6 years ago. I continue to be amazed at what I can plug into a USB port and have it "just work". And being open-source, if something is wrong or you just don't like the way it works you (or your hired programmer) can fix it. Try THAT with brand w or brand m. The only weak area is support for scanners. HP has great support. Canon is actively anti-Linux. The other brands are hit'n'miss. We solved that problem by buying HP scanners, most of them a generation old and dirt-cheap. Many windoze programs will run in WINE. IMO, the best newsreader is Forte' Agent. Windows only. I'm using it to post this message and it's running in WINE and looks just like a native Linux application. For those that don't work in WINE that I absolutely have to have, I keep a virtual machine with XP on it on my desktop. When it BSODs, I simply close the window and open another one :-) Part of the Linux creedo is "thow shall not break binaries". I don't recall an instance of that happening with Ubuntu, at least. John John DeArmond http://www.neon-john.com http://www.fluxeon.com Tellico Plains, Occupied TN See website for email address
On 08/26/2014 07:26 PM, John Miles, KE5FX wrote:
> On Tuesday, August 26, 2014 3:58:50 PM UTC-7, Tim Williams wrote: >> "ChesterW" <iamsnoozin@yahoo.com> wrote in message >> >> news:Fu2Lv.84945$O13.31767@fx17.iad... >> >>> Dear Group, >> >>> >> >>> I can finally afford a new oscilloscope to supplement my trusty >>> TEK >> >>> 465M. My budget is around $3k. I like the newer Agilent scopes, >>> which I >> >>> have used when someone else was paying. I do mostly low >>> frequency >> >>> high-precision instruments (analog signals less than about 1 >>> MHz).
>> >>> The pretty lower-end Agilent scopes are in reach, but I'm >>> tempted to use one of these: >>> >>> http://tinyurl.com/k88x74r >>> >> >>> which is driven internally with an FPGA and one of these ADCs >>> http://www.mouser.com/catalog/specsheets/DataSheetASD5020HS_v2.0.pdf >>> >>>
I make out the ENOB to be 11.6 bits at 125 MSPS with 14 bit samples
>>> using 4 channels, and 13.2 bits with 16 bit samples at 62.5 MSPS >>> using one channel. It will also go out to 1 GSPS with 8 bit >>> samples. Analog BW is 200 MHz. >> >>> >> >>> I like the serial decoding for free and the ability to stream >>> data to an external application for creating custom processing. >>> I'm thinking this would be good for prototyping AFEs with signal >>> processing via the PC. >> >>> So my thinking is that using this rather obscure configurable ADC >>> that these guys improve performance over the big manufacturers >>> ASICs for my particular applications niche. >> >>> >> >>> What do you think? >> >>> >> >>> ChesterW >> >>> > > At the $3K level he will be (or should be) looking at an Agilent > DSO2000-X or DSO3000-X series, or one of the lower-end DSO6000A > series, not one of the rebadged Rigols. He should buy a gently used > one on eBay if necessary to meet the budget. It is worth it. > Agilent has beaten everybody else's DSOs to a bloody pulp over the > last few years. > > Re: NeonJohn's comment, he's spot on. A USB oscilloscope is like a > USB handgun. (And I say this as a designer of USB test gear. > Headless instrumentation can be great, but not for something as > fundamental as an oscilloscope or DMM.) > > Re: Phil's comment, I like my 694C immensely, but every time I turn > it on I have to wonder if this is the last day on the job for its > trigger chip. Also, the probes can be stupidly expensive. I don't > think the 694C (or any 50-ohm only scope) is a good choice for a > general purpose bench tool. It's better as a pinch hitter for a > newer, slower DSO.
My 694C is actually a pre-production model that an old Tek guy upgraded with a brand-new CRT and a few options. If the trigger chip hasn't died yet, I'm not too worried. And I have a bunch of FET probes (P6201 1.1 GHz and P6249 4-GHz), so the 50-ohm input isn't an issue unless I were to turn the offset pot on the P6201 too far and roast the termination resistor in the scope front end. A trap for young players, for sure. If the OP needs the mixed-domain capability, then I agree that the newish ones are best, but you can get a 4-channel, 500 MHz digital scope for way under $1k on eBay--my last one was $465, and works brilliantly. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net
On Wed, 27 Aug 2014 14:44:38 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>On 08/26/2014 07:26 PM, John Miles, KE5FX wrote: >> On Tuesday, August 26, 2014 3:58:50 PM UTC-7, Tim Williams wrote: >>> "ChesterW" <iamsnoozin@yahoo.com> wrote in message >>> >>> news:Fu2Lv.84945$O13.31767@fx17.iad... >>> >>>> Dear Group, >>> >>>> >>> >>>> I can finally afford a new oscilloscope to supplement my trusty >>>> TEK >>> >>>> 465M. My budget is around $3k. I like the newer Agilent scopes, >>>> which I >>> >>>> have used when someone else was paying. I do mostly low >>>> frequency >>> >>>> high-precision instruments (analog signals less than about 1 >>>> MHz). > >>> >>>> The pretty lower-end Agilent scopes are in reach, but I'm >>>> tempted to use one of these: >>>> >>>> http://tinyurl.com/k88x74r >>>> >>> >>>> which is driven internally with an FPGA and one of these ADCs >>>> http://www.mouser.com/catalog/specsheets/DataSheetASD5020HS_v2.0.pdf >>>> >>>> >I make out the ENOB to be 11.6 bits at 125 MSPS with 14 bit samples >>>> using 4 channels, and 13.2 bits with 16 bit samples at 62.5 MSPS >>>> using one channel. It will also go out to 1 GSPS with 8 bit >>>> samples. Analog BW is 200 MHz. >>> >>>> >>> >>>> I like the serial decoding for free and the ability to stream >>>> data to an external application for creating custom processing. >>>> I'm thinking this would be good for prototyping AFEs with signal >>>> processing via the PC. >>> >>>> So my thinking is that using this rather obscure configurable ADC >>>> that these guys improve performance over the big manufacturers >>>> ASICs for my particular applications niche. >>> >>>> >>> >>>> What do you think? >>> >>>> >>> >>>> ChesterW >>> >>>> >> >> At the $3K level he will be (or should be) looking at an Agilent >> DSO2000-X or DSO3000-X series, or one of the lower-end DSO6000A >> series, not one of the rebadged Rigols. He should buy a gently used >> one on eBay if necessary to meet the budget. It is worth it. >> Agilent has beaten everybody else's DSOs to a bloody pulp over the >> last few years. >> >> Re: NeonJohn's comment, he's spot on. A USB oscilloscope is like a >> USB handgun. (And I say this as a designer of USB test gear. >> Headless instrumentation can be great, but not for something as >> fundamental as an oscilloscope or DMM.) >> >> Re: Phil's comment, I like my 694C immensely, but every time I turn >> it on I have to wonder if this is the last day on the job for its >> trigger chip. Also, the probes can be stupidly expensive. I don't >> think the 694C (or any 50-ohm only scope) is a good choice for a >> general purpose bench tool. It's better as a pinch hitter for a >> newer, slower DSO. > >My 694C is actually a pre-production model that an old Tek guy upgraded >with a brand-new CRT and a few options. If the trigger chip hasn't died >yet, I'm not too worried. And I have a bunch of FET probes (P6201 1.1 >GHz and P6249 4-GHz), so the 50-ohm input isn't an issue unless I were >to turn the offset pot on the P6201 too far and roast the termination >resistor in the scope front end. A trap for young players, for sure. > >If the OP needs the mixed-domain capability, then I agree that the >newish ones are best, but you can get a 4-channel, 500 MHz digital scope >for way under $1k on eBay--my last one was $465, and works brilliantly. > >Cheers > >Phil Hobbs
We have the 1 GHz Rigol, and it's a great scope. The screen is home-theatre size. https://dl.dropboxusercontent.com/u/53724080/Gear/Rigol/Rigol_1GHz.JPG
On Wednesday, August 27, 2014 4:42:10 AM UTC-7, JW wrote:

> Now that it has an LCD, you could always keep it running=20 > 24/7 if you suspect it happens on a power up, . :) I suspect that many=20 > of these scopes spent most of their lives turned on which is why there's=
=20
> so many of them with dim CRTs and loaded with dust inside.
Yep, no doubt about that. I don't know enough about them to speculate as t= o whether the failures are initiated by power-up events or heat over time. = The trigger chips don't really get that hot, at least with the cover on. = Either way, the number of 694Cs for sale with similar faults does make me a= bit nervous about using this one when I don't need the bandwidth. =20
> Were you ever able to fix or diagnose the other 694C you bought?
I poked around at it for a while but couldn't determine where to pin the bl= ame in the limited time I had. It's unfortunate that there are no schemati= cs for it. There are a lot of similarities vis-a-vis the TDS 520B road map= , but also a lot of differences. It's possible that the problem isn't even= in an ASIC, since the 694C actually has more LSI-ish parts in its trigger = subsystem than the 520B does. =20 Some of the signal-conditioning chips could probably be replaced by ADCMP58= 0s or the like. But without a schematic, that amounts to a research projec= t.
> Jay (Who sold you your working one...)
It's been great. I don't know if you saw my post on TekScopes, but I actua= lly replaced your panel with a different one ( http://www.ke5fx.com/tds694_= lcd2.jpg ). The image quality was fine before, but matching the scope's na= tive 640x480 resolution made it look even better. -- john, KE5FX
rickman <gnuarm@gmail.com> wrote:
> I have been wanting to switch to Linux for some time now but never > made the jump.
I made the jump over 10 years ago at home. At work, sometimes I have had Linux and sometimes not.
> I may be mistaken but I believe a Linux compatible device is much less > likely to be broken by new versions of the OS, no?
Like everybody else has said: If the widget has some "standard" external interface, like USB, Ethernet, or RS-232, then it is more likely to continue working on Linux. (Note that PCI, PCI Express, ISA, PCMCIA, etc, do *not* count, here.) If you have, or can get, source code for the drivers, then it is more likely to continue working on Linux. (This might mean that *you* have to make it work, but you can get it done.) Some other points: If the widget documentation mentions a particular version of Linux, sometimes that just means "that's all we tested it on, but it will probably work on other stuff", but sometimes it means "that's all it will work on". My standard approach is to pretty much ignore what the vendor says about Linux compatibility, and either look for feedback from users, or get one and try it. If I can get a sample widget, my usual test is to plug it into an absolutely stock Linux install and see what happens. The more functionality I get from it, the happier I am. Look around and see if there is any kind of hobbyist/enthusiast community online for your proposed device. (This is more likely for less expensive devices, but I'm sure there are people out there that use 1 GHz A/D cards for fun.) These groups often have good information on what it takes to get things running under Linux. If the widget comes with a kernel module (a file like foo_driver.ko that you have to insmod), look at the kernel messages when the module is inserted (use the dmesg command). Sometimes this happens at boot time, and sometimes it happens when you first plug in / power up the device. In my experience, the kernel people are pretty good at warning you about upcoming changes, if you know to look for the warnings. If you see things like warning: foo_driver.ko uses obsolete setup_special(), it should be changed to use setup_generic() in the kernel messages, that's a mark against that widget. Over time, Linux is developing the ability for some drivers to run in user-land rather than in kernel space. This makes it a little bit easier for non-root users to install (and develop, if needed) drivers. If you have an extremely high-performance device, this may not work as well, though. A few months ago, I wrote a more extensive post about getting a device supported under Linux: https://groups.google.com/forum/#!original/sci.electronics.design/6qjEouxsjbQ/mR6v5P4uGcwJ or <https://groups.google.com/forum/#!original/sci.electronics.design/6qjEouxsjbQ/mR6v5P4uGcwJ> or even http://is.gd/jTGcUo
> I won't buy a LogicPort from Intronix because they don't support Linux > or Android.
The phone stuff changes often enough that I don't care too much about whether a widget supports it or not. These days, the answer for some widgets is that the widget should have a little Web server in it, and then I can access it via Wi-Fi or Ethernet with whatever browser I have handy - desktop, laptop, tablet, smartphone, etc. It can use HTTP for setup and slow-to-medium data, and some kind of direct TCP or UDP connection for fast data. Matt Roberds
On Tue, 26 Aug 2014 23:18:34 -0400, rickman <gnuarm@gmail.com> wrote:

>On 8/26/2014 7:56 PM, John Miles, KE5FX wrote: >> On Tuesday, August 26, 2014 4:34:43 PM UTC-7, rickman wrote: >>> I'm confused. Tim is saying Agilent and Rigol scopes are the same >>> thing. Why do you say the OP should be looking at an Agilent scope? >> >> Only the very lowest-end Agilent scopes were made by Rigol, and I'm not sure they even still sell those. The rest are designed in-house. >> >>> I can't agree with this. I have held off buying a new scope >>> for some time now while I continue to look for a good inexpensive >>> mixed signal USB headless scope. There are a couple of Hantek >>> units I am considering. >> >> Better than nothing, obviously. But when you're looking to spend multiple thousands of dollars, the mainstream brands have some appeal over whatever Harbor Freight is importing this week. > >Why would anyone be "looking" to spend some thousands of dollars? I am >looking for a set of features and specs and want the lowest price I can >find for them. > >I've actually never understood why oscilloscopes are so expensive >actually. I get that there is a lot of R&D that goes into them, but >once you have a solid design I would think that could be used for a lot >of scopes and that NRE could be amortized.
The market is still very small.