Both scopes can be turned into DS1104Z’s quickly and easily, but I don’t think it’s exactly legal. I have a DS1074Z (DS1054Z wasn’t out yet), and enjoy it. At the point you are willing to lay down the cash for the PicoScope you are quickly getting into the Rigol price range. I’ve had too many bad experiences with these cheap oscilloscopes in the hands of inexperienced users to make a suggestion for any of them without making protection circuits. That written, you can get the PicoScope that can greatly exceed those limits and the trick is the way they manage the interface and the cost of doing it shows in the price of the unit. So maybe with some simple compression and messing around one can wiggle an 8MHz 12bit DSO out of an USB2 port and we are making some very real assumptions about what your computer can actually handle. In reality without some messing around that’s not a whole lot when you consider the information above. So maybe at 12 bits per sample you could max shove 40Msps down an USB2 interface. Any more vertical resolution and your maximum horizontal sampling rate pays for it. So unless you are running burst measurements in which the data stays in the external device till it fills, that is a hypothetical limit of 60Msps with just 256 vertical steps (256 potential voltages readings vertically in 1 byte and let us cheat and assume we deliver the digitized signal AC coupled with a DC offset value such that DC offset at the analog input does not play havoc).
So assuming you want to free run this oscilloscope you have 60MBps (480Mbps) max into the PC without some compression. Now let’s add to the mix that we’ve put USB in there and assume you want the minimum of USB2. So basically if you’ve got a 10Msps ADC you can probably capture barely viable information on up to 5MHz and really probably will find the best use down below 1MHz. Anywhere approaching Nyquist rate and such advertisements are generally baseless with some exceptions that you are not likely to find in cheap hardware. Watch for dirty things with cheap DSO like listing the sampling rate of the ADC advertised as the maximum useful frequency the DSO can be used on. The result being spurious readings or poor capture of incidents that might be important to the viewer.
The other risk is that there are limits in the digital sampling performance and transfer capability. Depending on what you are measuring this could actually result in damage to something. I agree with Marshall the Rigol DSO are nice and great for the price but the price for the other units mentioned in the OP are just too low.Ī serious risk that is taken with such low prices is compromises in the analog front end that increase the likelihood of incorrect readings and coupling into the circuit under test. However, I have more or less decided to get a dedicated oscilloscope and the experience with this cheap one has shown me the sort of features I need to look at carefully when choosing the next one.If you dive into oscilloscopes deep enough you will quickly realize you get what you pay for.
This free software support could be very important if you buy one of these USB oscilloscopes where the supplied software does not match your PC Windows version. It is supported by Sigrok free software, which may do a better job, and I may look at that. This makes it useless, for example, for attempting to analyse a protocol. But, there is no continuous time line between the pages, so it is not transparent how much data is missing between the extents of the pages. On a specific page, you can even navigate a bit forwards/backwards.
If you are recording a signal burst, it is recorded over a series of disjoint pages (with an unspecified amount of data missing between the pages). The biggest limitation, that is which is not clear from the specification, is the recording function is rather weak. They are OK for things like seeing if there is some life on an Arduino pin or looking at constant waveforms. These have the advantage of being cheap and compact.
I have one of these Sainsmart DDS-120 at the moment: DDS-120 PC-based Virtual Oscilloscope, Silver [US ONLY –