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Products => Test Equipment => Topic started by: moemoe on March 18, 2013, 12:04:01 pm

Title: Dave's cheatsheet for budget oscilloscope testing
Post by: moemoe on March 18, 2013, 12:04:01 pm
Hi,

as Dave offered to test some budget scopes, I thought starting a new thread to collect proposals would be a good idea:

I have an open invitation to review/teardown/test/play with any product from Trio Smart Cal just down the road:
www.triosmartcal.com.au (http://www.triosmartcal.com.au)
And they usually have all the stuff in stock.
The problem isn't so much getting gear, it's the time and effort it takes to review advanced gear like scopes. And that's on top of my already backlogged list of review items!
I'd love to do a budget scope shootout, it's a just a matter of finding 2-3 days free to do it.
Of course I could try a "simplistic" or "basic" comparison review of the major features, but you know me...  :palm:
But I do plan to be that rigid with my next multimeter shootout - test X features, X time limit on each one, and no tangents.

So if someone was to come up with a list of scopes, and a list of basic features they think would cover the basics, it's doable...

For the products, I would set the limit to 400$, so at triosmartcal the following products fit within this limit:


Missing:

And now I think we should just collect what we would like to have tested, put together informations like available bandwidth hacks etc…

Please keep in mind that they should be available fom www.triosmartcal.com.au (http://www.triosmartcal.com.au), see quote above.
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: moemoe on March 18, 2013, 12:13:13 pm
For the Tekway/Hantek/Voltcraft model, they are all the same:

Input linearity and pulse response: http://www.mikrocontroller.net/attachment/173049/mod_input_circuit.pdf (http://www.mikrocontroller.net/attachment/173049/mod_input_circuit.pdf) – compare with the other models.

200MHz Hack https://www.eevblog.com/forum/chat/hantek-tekway-dso-hack-get-200mhz-bw-for-free/msg91877/#msg91877 (https://www.eevblog.com/forum/chat/hantek-tekway-dso-hack-get-200mhz-bw-for-free/msg91877/#msg91877)


The same applies to the Rigol, but 100MHz: https://www.eevblog.com/forum/blog/changing-the-rigol-ds1052e-to-ds1102e-using-usb-the-dummy-guide/ (https://www.eevblog.com/forum/blog/changing-the-rigol-ds1052e-to-ds1102e-using-usb-the-dummy-guide/)
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: SLJ on March 18, 2013, 01:39:19 pm
I would like to see comparisons of screen shots and refresh rates/update speed of the USB/Serial PC interfaces.
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: Hydrawerk on March 18, 2013, 09:42:53 pm
UNIQUE UQ2062C DIGITAL OSCILLOSCOPE, 60 MHZ, 500 MSA/S
is very similar to some UNI-T bench scope...
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: S_Prime on March 19, 2013, 08:25:51 am
Other possible entries:
OWON SDS7102V 100MHz, 1G/s
Uni-T UTD2102CEL 100MHz, 1G/s
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: AndyC_772 on March 19, 2013, 08:44:46 am
For any of these budget scopes, I'd like to see a comparison showing how they display a complex or unstable signal, compared to how an analogue scope or a better DSO with an intensity graded display would show it. Maybe compare the same signal displayed on a Rigol 2000 series, which is about the lowest cost scope I'd personally regard as suitable for frustration-free lab use. To be really thorough, compare with the MSOX3054A as well, just to highlight what (if anything) a top of the line scope would be able to add under the circumstances.

It's all well and good showing nice clean, stable waveforms from a signal generator, but that's not the sort of thing I usually probe. I want to see how often a chip select goes active, or measure the time between a trigger pulse and an ultrasonic burst, or look at the timing jitter on an SPDIF signal.

Moreover, I want these things to be clear by looking at the screen, not by resorting to years of experience in how to set up a scope to best show one particular effect most clearly. These are entry-level scopes, most likely to be used by people who just don't have that experience, and who are most likely to be confused or misled.
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: SLJ on March 19, 2013, 11:02:53 am
My suspicion is that a low end digital scope will be more useful useful for the waveform data it will display and store than for the displayed waveform itself.  I would think the screen is not high enough resolution.  It might be OK for signal tracing if the triggering is stable enough.  I would not give up my analog Tek scope for troubleshooting but I suspect the waveform and pulse data a low end digital scope will display will be a nice addition without spending too much money.  I'll know more once the new one arrives and I get a chance to compare the displayed data with my analog scope, my meters, and frequency counters.
Title: My suggestions for Dave's budget oscilloscope test
Post by: rstoer on March 20, 2013, 01:19:57 am
This is my first post here and I must start by giving a quick shout-out to Dave for the great job he’s done with his video blog. I’ve been watching incessantly since finding them on U-Tube about a month ago. I think I’m addicted. Dave, you have another fan in the USA (Although you were wrong in trashing Panasonic plasmas. Despite your unfortunate issue they make the best ones on the market).

With that out of the way, I’d like to suggest a group of Chinese DSO’s for the shootout. The ones I’ve chosen are all two-channel, 100MHz, with 1 GSa/s real sampling. They all have 7” or larger screens (although resolutions vary) as I believe that’s what most people are looking for today. Lastly they all can be purchased in the U.S., from U.S. sources, for between $350-450. Here’s my list, in alphabetical order:

Atten ADS1102CAL (I believe this is sourced from Siglent and may very similar to the SDS1102CNL)
Hantek DSO5102B (Tekway is not sold in the US but I believe their DST1102B is identical to this Hantek model)
Owon SDS7102V
Siglent SDS1102CNL
Uni-T UTD2102CEL
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: PA4TIM on March 20, 2013, 10:01:46 am
For any of these budget scopes, I'd like to see a comparison showing how they display a complex or unstable signal, compared to how an analogue scope or a better DSO with an intensity graded display would show it. Maybe compare the same signal displayed on a Rigol 2000 series, which is about the lowest cost scope I'd personally regard as suitable for frustration-free lab use. To be really thorough, compare with the MSOX3054A as well, just to highlight what (if anything) a top of the line scope would be able to add under the circumstances.

It's all well and good showing nice clean, stable waveforms from a signal generator, but that's not the sort of thing I usually probe. I want to see how often a chip select goes active, or measure the time between a trigger pulse and an ultrasonic burst, or look at the timing jitter on an SPDIF signal.

Moreover, I want these things to be clear by looking at the screen, not by resorting to years of experience in how to set up a scope to best show one particular effect most clearly. These are entry-level scopes, most likely to be used by people who just don't have that experience, and who are most likely to be confused or misled.

I agree, they are used to meaure signals, so that is what they should do, the sad thing most reviews are about what they can do in theory and not how well they do that. A compare to a high end scope is not a bad compare, it is a way of showing how well or bad the others are. Like hooking up a multimeter to a clibrator or comparing it to a 3458. This has nothing to do with the useless tight ass expression bang for bucks. Bang for bucks is only usefull if you know the bang and its worth the buck, in other worde, is it usefull or useless.

If the timebase is stated 2% but meaures 5 % off, that can be a poblem and then you waisted money, if 5 % is OK by you, then it could be a bang for bucks, but if these things are not tested you do not know and can not tell is the bang is worth the box and you only give it a " value " based on nice olors, knobs, giftbox, build quality ( you can build a bad design still very nice and solid, but performance still sucks ! )

The multimeter shootout was fun, lots of info about the beeper, fuses, sturdy cases ect but what does that meter do on DC with ripple, on a AC signal with offset, on changing dutycycle, under temperature, with a half full battery, how accurate is it, and over time.
It is nice probes look OK, but looks are not everything, the probes from a Keithley 2000 looks like old fasioned, no fancy adapters, just wire and hardplastic classic probes. dave would say nah, and trow them over his shouldeR, but they are exellentvand well thought but without a fancy high tech look and feel. Some very nice looking cheap pobes have almost no copper inside and a > 1 Ohm resistance.
I have seen groundclips from scope probes just pressfit to the crock without removing the plastic, or a multimeter that used a resistive voltage devider from the battery as a Vref. Ect.

So the new moto should be not ; lets take it appart after verification of proper operation within specs

Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: moemoe on March 20, 2013, 11:15:27 am
Please keep in mind that those should be available at http://www.triosmartcal.com.au/, (http://www.triosmartcal.com.au/,) as Dave can get them as testing sample from there.

Hantek DSO5102B (Tekway is not sold in the US but I believe their DST1102B is identical to this Hantek model)

Yes, they are the same, and the Tekway DST1062B is also the same – just one click in the bandwith unlock tool to convert them into each other.
Title: Re: Dave's cheatsheet for budget oscilloscope testing
Post by: rstoer on March 20, 2013, 12:20:39 pm
Please keep in mind that those should be available at http://www.triosmartcal.com.au/, (http://www.triosmartcal.com.au/,) as Dave can get them as testing sample from there.

Thanks. I checked and if you sub the identical Tekway DST1102B for the Hantek all but the UNI-T are available through Trio. However Trio's 'Unique' brand looks identical to the UNI-T (although they only list the 60 MHz model). That could serve in a pinch or possibly they could supply the 100 MHz version.