EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: retrev on June 05, 2017, 04:48:49 pm
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I know there are of few of these out there but it seems like it's been a few months and the YouTube channel has a couple of newer reviews in the entry level scope category. So, recommendations for an entry level scope? Here are some loose requirements.
- Under $400 USD (ish)
- At least 2 channel with external trigger (4 is better)
- The ability to pull data into a PC (USB/network connection or storage to USB/SD with an accessible data format)
- Strong preference for basic protocol decoding. At least SPI and I2C. LIN, CAN, 1-wire, etc. are always nice additions.
- Adequate bandwidth to work with common hobbyist gear such as arduino boards and such.
- Basic FFT/spectrum is strongly desired. Enough capability for audio level data, possibly some ISM band RF.
Is all this too much to ask for in a scope? I know the DS1052e was quite popular because it was pretty easy to hack into a 100MHz scope. The DS1054Z seems to be pretty popular too (is the same hack possible?) What about some lesser known or newer brands?
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Get a DS1054Z.
Yes, it's completely hackable: http://gotroot.ca/rigol/riglol/ (http://gotroot.ca/rigol/riglol/)
PS: Use option "DSER" even though it's not on that list. DSER is the one to go for... ;)
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Yeah it's pretty hard to beat the Rigol DS1054Z for a new entry level DSO on a budget. It can be hacked easily to 100MHz bandwidth.
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The advent of the Siglent SDS-1202X-E has made things much more interesting in the entry-level arena. 200MHz bandwidth, full decoding, and an FFT that is much better than that of the Rigol DS-1054Z. And a substantially more responsive user interface as well.
If you can live with 2 channels + external trigger (which, near as I can tell, sadly cannot be used as a direct channel for protocol decoding), then it may be the scope for you. Regardless, it's probably worth checking out.
Note that it is a new entry into the arena, so it's got some teething issues. It remains to be seen how quickly those get sorted.
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And let's not forget about the MicSig TO1000 series. Also in the same pricerange for the 70MHz models and it has 4 channels. Decoding is in beta stage but it is looking promising. The rest of the firmware seems to be working well.
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As a Keysight guy I feel obligated to put a word in for the InfiniiVision 1000 X-Series, of course, though it may be a little more expensive than what you are looking for. 2 analog, 1 digital channel, decoding (extra $ until it gets hacked), really good FFT for it's class of scope. :-+
Other people have commented on it in this forum if you're looking for a less biased review. This was a pretty thorough third party review: http://hackaday.com/2017/05/02/scope-review-keysight-1000-x-series/ (http://hackaday.com/2017/05/02/scope-review-keysight-1000-x-series/)
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If you can live with 2 channels + external trigger (which, near as I can tell, sadly cannot be used as a direct channel for protocol decoding), then it may be the scope for you.
He said "Arduino" so 2 channels will be limiting.
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As a Keysight guy I feel obligated to put a word in for the InfiniiVision 1000 X-Series, of course, though it may be a little more expensive than what you are looking for. 2 analog, 1 digital channel, decoding (extra $ until it gets hacked), really good FFT for it's class of scope. :-+
Other people have commented on it in this forum if you're looking for a less biased review. This was a pretty thorough third party review: http://hackaday.com/2017/05/02/scope-review-keysight-1000-x-series/ (http://hackaday.com/2017/05/02/scope-review-keysight-1000-x-series/)
I'd like to help with the hacking effort - can I borrow a 1000 X for a few months? >:D
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I have a 4 channel scope, but personally I find that I rarely use 4 channels at once. If decoding is a priority then in most cases an inexpensive PC based logic analyzer will outperform a scope for that task.
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As a Keysight guy I feel obligated to put a word in for the InfiniiVision 1000 X-Series, of course, though it may be a little more expensive than what you are looking for. 2 analog, 1 digital channel, decoding (extra $ until it gets hacked), really good FFT for it's class of scope. :-+
Other people have commented on it in this forum if you're looking for a less biased review. This was a pretty thorough third party review: http://hackaday.com/2017/05/02/scope-review-keysight-1000-x-series/ (http://hackaday.com/2017/05/02/scope-review-keysight-1000-x-series/)
I'd like to help with the hacking effort - can I borrow a 1000 X for a few months? >:D
The real challenge is to bring the basic EDUX1002A to a full DSOX1102G, as it requires software hack + hardware mods.
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If you can live with 2 channels + external trigger (which, near as I can tell, sadly cannot be used as a direct channel for protocol decoding), then it may be the scope for you.
He said "Arduino" so 2 channels will be limiting.
I bought the DS1054Z specifically for the 4 channels. The 100 MHz bandwidth is limiting in that I can only display up to the 7th harmonic of a 15 MHz square wave. Square waves are tough - it takes at least up the the 7th harmonic to get anything that even approximates square.
That may be fast enough for antyhing an Arduino can do but when we get to ARM chips, signal frequencies can get up there.
It is nice to use 4 channels to watch SPI. Yes, it can be done with a logic analyzer and probably should be. But if you want to see a good rendition of the actual signal you need bandwidth.
I'll hold on to my 350 MHz Tek 485 for quite a while.
For 2 channels, I would give a lot of consideration to the Siglent SDS1202X-E. It's 200 MHz and brand new. It looks great!
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I just bought the Siglent SDS1202X-E. While I've been running into a few bugs overall I'm impressed with the horsepower. The History feature has come in handy a few times and I really like having direct controls for the two channels and direct access to Auto or Norm.
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I think for "entry level" 100MHz is a good number to shoot for. Sure you might not get crisp edges on square waves at higher frequencies but how often does that matter? *All* scopes will occasionally lie to you, learning about the limitations and how to interpret what they show you is a significant part of learning how to use an oscilloscope. You can never have too much bandwidth available but bandwidth is expensive and it's important to not get too hung up on it unless you know you actually need more. I think for most beginners just learning proper probing techniques to get even 100MHz of useful bandwidth is a handful.
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I bought the DS1054Z specifically for the 4 channels. The 100 MHz bandwidth is limiting in that I can only display up to the 7th harmonic of a 15 MHz square wave. Square waves are tough - it takes at least up the the 7th harmonic to get anything that even approximates square.
Sure, but if you know that then it's much less of a problem. [bi]No[/b] 'scope is going to show a perfect square wave.
That may be fast enough for antyhing an Arduino can do but when we get to ARM chips, signal frequencies can get up there.
ARM chips can easily go too high for your 350MHz Tek. :popcorn:
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I bought the DS1054Z specifically for the 4 channels. The 100 MHz bandwidth is limiting in that I can only display up to the 7th harmonic of a 15 MHz square wave. Square waves are tough - it takes at least up the the 7th harmonic to get anything that even approximates square.
Sure, but if you know that then it's much less of a problem. [bi]No[/b] 'scope is going to show a perfect square wave.
That may be fast enough for antyhing an Arduino can do but when we get to ARM chips, signal frequencies can get up there.
ARM chips can easily go too high for your 350MHz Tek. :popcorn:
IO peripherals like PWM, SPI, I2C, serial, lights and knobs rarely run at high frequencies but external SDRAM is a challenge as is Ethernet and USB. So, yes, even 350 MHz is limiting. Funny thing is, even a 1 GHz scope would have difficulty with SDRAM and timing is often very tight!
Back when I played with cars, there was a saying "Speed costs money! How fast can you afford to go?". Same thing with scopes.
The problem when viewing square waves that look like sine waves is trying to figure out if you met the setup and hold times.
I guess it is important to recognize that we are talking about an 'entry level' scope that should be capable of doing 'entry level' work. Now all we need to do is define 'entry level' work! I don't think SDRAM is included... I'm pretty sure everything an Arduino can do is included but a 600 MHz Blackfin uC probably isn't. FPGAs might be included it they are emulating simple peripherals but FPGAs are used for speed so it depends on the project.
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The problem when viewing square waves that look like sine waves is trying to figure out if you met the setup and hold times.
For that sort of stuff you use a real logic analyser. Getting 8Gs/s (125ps timing resolution) is very affordable nowadays and 50Gs/s (40ps) is not out of the question either.
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It all comes down to using the right tool for the job. A scope is arguably the most versatile instrument and can wear many hats so to speak, but when you need performance in a more specialized area often it's more economical to use a more specialized tool.