DS203, a decent, compact, simple oscilloscope at a nice price.

Another instrument joins my collection :).
I've wanted a toy like this for a long time. It's hard to call it a full-fledged oscilloscope; it has its drawbacks, but its low price more than makes up for them.
This model was reviewed quite recently, so this review will just add a few details and my comments.


Rather than reinvent the wheel, I'll start with the usual stuff. The package arrived pretty quickly, in 13 days, and the seller shipped it almost immediately.
The only thing that disappointed me was that the price was $127 when I bought it, with a discount. Once the sale ended, the seller dropped the price even further, to $124. It's a small thing, but still disappointing.

It came in a little box inside a regular mailer bag. Nothing unusual.


Nothing inside was damaged. The box is quite sturdy, but after unpacking it, I tried to put everything back the way it was and couldn't manage it—the box wouldn't close :)
That's everything that came in the package.
Unlike the previous review of this product, this package doesn't include the two probes for the digital inputs. That's a drawback, of course, but I didn't really need them. Besides, if you really need to, you can connect regular probes instead and even measure higher-voltage signals (though not always).


The oscilloscope itself was packed in a small case and wrapped in a plastic bag.
My colleague ksiman wrote that he wasn't too keen on how the little case closes. I have to disagree: I found it convenient, though that's a matter of personal preference.
The case material, on the other hand, is a poor choice. I can guarantee that 99.(9)% of the dust on your desk will end up on it. Still, it feels very nice in your hands.


The screen has a protective film on it. It was still there in the photo, but I've since removed it.


Two probes are included. The seller's listing said two digital probes and one regular probe, but this is what arrived. I didn't open a dispute; this setup is actually more convenient for me.


Specifications, copied from our friend ksiman's review



The kit also includes a USB-to-mini-USB cable. It's just a cable, and charging works without any problems.


The kit includes the little tool for taking it apart, which has become standard with this oscilloscope.


And there's a manual in English and Chinese. There's a Russian manual online, so the English one isn't much use to our readers.


The oscilloscope's case is made of blackened aluminum (presumably), and you can feel its weight.
The previous review listed its weight as 120 grams.
The model is marked on the back (yes, it's a DS203, not a DSQ203).


This is where I couldn't understand what stopped them from adding a fold-out stand on the back, so you could prop the oscilloscope up at an angle on the desk. It would have cost next to nothing and made it a thousand times more convenient. For example, like they did with the game console from the last century—

The left side has connectors for the built-in function generator output and the two analog inputs.


On the right side are the digital inputs, a USB port for charging and connecting to a computer (you can't monitor signals in real time), and the power switch.


On top are the control buttons and two slider switches, each combined with an additional button.
The buttons are used as follows:
1 — Hold: freeze the measurement results on screen.
2 — Settings menu, saving screenshots and settings, and calibration.
3 — Displays additional signal parameters such as frequency and duty cycle, as well as the battery voltage.
4 — Switches to the mode for configuring the trigger controls and so on.
5 — Slider switch: controls the input voltage divider, timebase, digital channel enable/disable, and so on. Pressing it changes the operating mode; for example, you can select AC or DC coupling for the desired channel and change that channel's divider.
6 — Selects the parameter to adjust (channel 1, channel 2, etc.).
Rather than go into all the details, here's a description of every menu item.


Since there are few buttons but lots of modes, each button has a lot of functions assigned to it. The oscilloscope is very awkward to use at first, but you get used to it.
The engineers deserve credit for this design: fitting controls for a fairly complex instrument into 6 buttons and two switches is no easy task.
I liked that the brightness and volume settings have plenty of levels, so you can adjust them to your liking. (I ended up setting the volume to the lowest level, but didn't turn it off.)


Inside are the battery and the main board with the display and all the electronics, shielded by a metal cover. Be careful with the buttons when taking it apart—they tend to fall out. :)


This is how it comes apart after removing four screws and disconnecting one connector.
A brief digression. At the beginning, I mentioned that this oscilloscope is the same as the one in my previous review.
Even the battery's production date is the same. I suspect they're from the same batch, just sold by different sellers.


The marking on the board is slightly different, though: mine says T20 14 18, while the one in the previous review says T20 14 30.


The components for calibration and adjustment are under the battery. I don't recommend touching them.


The startup screen when the instrument boots.
Is it just me, or is there a typo in the last line? It says Form, but should it say From?


The instrument's interface. Since the screen resolution is only 400x240 pixels, everything is kept very concise.



And, as always, additional materials are in the attachment.
People say that once something gets on the internet, it never disappears.
But I’ve often come across cases where the information I needed was no longer available. So I upload the additional materials to Yandex Disk. If anyone knows a more convenient place, I’d be glad to hear your suggestions.
The attachment includes the Russian-language manual, the instrument’s schematic, and tests of its bandwidth (not mine).

Summary.
Pros.
Good value for money.
A decent set of accessories; everything you need is included.
Thanks to its built-in battery, the oscilloscope can be used anywhere, not just near a power outlet.
2 analog channels and 2 digital channels, plus a built-in function generator.
Sturdy aluminum case.
Can save waveform screenshots.
Compact size.

Cons.
Rather mediocre specs. The QDSO has better specs in terms of frequency, but it has its own drawbacks: for example, it has no AC mode (you can put a capacitor in series with the input) and only one channel. The DS203 suited my work better.
The case design is inconvenient; it really needs a flip-out stand, so I’ll have to modify it.
The controls leave a lot to be desired :(
Its frequency response is on par with very inexpensive analog oscilloscopes.

My take.
It probably won’t replace a conventional oscilloscope; one doesn’t rule out the other. For a true replacement, you need to buy a more expensive unit (say, an order of magnitude more).
You’ll have to get used not only to the controls, but also to the quirks of working with digital oscilloscopes.
It could use an analog oscilloscope emulation mode, where brightness also conveys information (to put it simply).
But overall, it’s a very handy little thing. You can set it on your desk and see everything right in front of you, and it takes up very little space (especially compared with analog oscilloscopes).
I could have bought something better and more expensive, but lately I rarely use an oscilloscope, and the big analog one sitting on my desk had started to get on my nerves. So I decided to make do with this one. Maybe it’ll also help me decide whether I should buy something more substantial.
And I’m not getting rid of the analog one, because “it’s a good one” :)