DreamSourceLab DSTouch / DS4T1012 / DS4T252

[ptluis]

Again, it's a bit sad that they didn't invest a bit more thought/effort into the trigger system. E.g. a protocol trigger or at least something like triggering on the start/or stop bit of an UART communication would have been helpful.

Also, I understand that it's not possible to store the currently measured waveform and transfer it to the PC (offline). Obviously only screenshots and "session files" (settings) can be transferred to the PC. That's also a major letdown.

In what format to save waveform data? csv, bin?

[0xdeadbeef]

Whatever. Usually scopes offer both, a binary and csv format.

[Serg65536]

I'm glad that you like it, it's an addictive little device isn't it? If you have any suggestions to improve, like new functions, Ui, bugs, etc post here.

Thank you for the great device!

1) So far the major concern is the waveform save function!
It would be nice to set a button shortcut for it: power+start, or power+auto, or double power. Please, consider to make shortcuts for both the waveform save and the screenshot save command.
It would be much more effective to have a binary waveform save format. CSV format is storage space consuming.

2) FFT analysis function should have ability to turn off the waveform view.
To achieve the best FFT quality it's necessary to adjust waveform to fill all the screen space. But in this case the FFT graph become hardly readable.

3) It would be nice to have basic trigger information always on screen.
The "DreamSourceLab" text is NOT what users want to see there! It's reasonable to leave your logo in the corner, but NOT the full name.
Much better would be to see the trigger level, slope and channel information near the "trig" menu entry.

4) It would be nice to make the measurement stickers less prominent.
Please, consider to add transparency and make it dim. So that the waveform would be more visible in the area.

[ptluis]

I'm glad that you like it, it's an addictive little device isn't it? If you have any suggestions to improve, like new functions, Ui, bugs, etc post here.

Thank you for the great device!

1) So far the major concern is the waveform save function!
It would be nice to set a button shortcut for it: power+start, or power+auto, or double power. Please, consider to make shortcuts for both the waveform save and the screenshot save command.
It would be much more effective to have a binary waveform save format. CSV format is storage space consuming.

2) FFT analysis function should have ability to turn off the waveform view.
To achieve the best FFT quality it's necessary to adjust waveform to fill all the screen space. But in this case the FFT graph become hardly readable.

3) It would be nice to have basic trigger information always on screen.
The "DreamSourceLab" text is NOT what users want to see there! It's reasonable to leave your logo in the corner, but NOT the full name.
Much better would be to see the trigger level, slope and channel information near the "trig" menu entry.

4) It would be nice to make the measurement stickers less prominent.
Please, consider to add transparency and make it dim. So that the waveform would be more visible in the area.

Hi first let me clarify that I'm not DreamSourcelab team, I'm a user like you but I'm cooperating as a tester. I'm allowed to send information to a given email. I report back, bugs, desired features, suggestions, etc, etc they collect all info and their engineers will study the possibility to apply every information sent to a new firmware update. So we just have to wait and see.

Btw did you know you can move both V cursors at same time? the same with H cursors

[0xdeadbeef]

I just wonder: most people here fancy the 50MHz version. Is this because of the 1mV/div or the price or both?

[ychat]

I just wonder: most people here fancy the 50MHz version. Is this because of the 1mV/div or the price or both?

I think this is because with 1mV/div sensitivity and 2Mpts storage depth ds4t252 has no competition in the sub-$100 range.
But ds4t1012 price-wise is close to the entry-level 12 bit oscilloscopes, making it a hard choice.

[ptluis]

I just wonder: most people here fancy the 50MHz version. Is this because of the 1mV/div or the price or both?

I think this is because with 1mV/div sensitivity and 2Mpts storage depth ds4t252 has no competition in the sub-$100 range.
But ds4t1012 price-wise is close to the entry-level 12 bit oscilloscopes, making it a hard choice.

At 100 bucks, there's no competition on battery operated scopes, that offer the same quality. For me quality is not displaying beautiful graphics, UI, nice icons,etc it's all about thrust in what I see and the accuracy of what it can measure. 50MHz and 2M is more than enough for my objectives. I thought on buying the ds4t1012 but 1mV is more important to me than 16M deep memory or 150MHz bandwidth. Of course some polishing would be nice, and since they accepted my feedback, I'm cooperating with them looking forward for a new firmware release, it doesn't cost nothing to try right? even if they don't release a firmware update, the scope is more than enough for most of the tasks.  For me it was a good choice, specially having a device on my pocket with a long battery life.

[0xdeadbeef]

It's just that 200MSa/s are somewhat underwhelming, and 100MSa/s in dual channel mode are pretty much bottom (Shannon-Nyquist) level for a 50MHz scope.
The DS4T1012 has three times the bandwidth but five times the sample rate. And I guess there is absolutely no other pocket scope with 1GSa/s sampling rate or is there?

[ptluis]

It's just that 200MSa/s are somewhat underwhelming, and 100MSa/s in dual channel mode are pretty much bottom (Shannon-Nyquist) level for a 50MHz scope.
The DS4T1012 has three times the bandwidth but five times the sample rate. And I guess there is absolutely no other pocket scope with 1GSa/s sampling rate or is there?

 I don't know any other brand that offers the same in pocket size, this is the only i have found. There are some tablet cheap ones but not really of much use. If you don't really need a pocket one, you'll have options like the Rigol DHO800 series or the Owon ADS800A series. Both are able to be powered by USB-C port. Obviously not pocket size tho.

[0xdeadbeef]

I already have a proper desktop scope, I'm just toying with the idea of having something (very) portable.
But most probably I will be able to convince myself that I don't really need that anyway.

[Serg65536]

I already have a proper desktop scope, I'm just toying with the idea of having something (very) portable.
But most probably I will be able to convince myself that I don't really need that anyway.

This scope is really good at measuring differential voltages inside a circuit.

The lower the size - the higher impedance stuff you can measure. You can just connect it without a probe with a short wire.
There could be no match from mains powered or big oscilloscopes.

No currents from a mains PS,
no antena effects, no
noise picked up from a probe.
Multiply this by 1mV sensitivity!

Perfect!

[ptluis]

I already have a proper desktop scope, I'm just toying with the idea of having something (very) portable.
But most probably I will be able to convince myself that I don't really need that anyway.

This scope is really good at measuring differential voltages inside a circuit.

The lower the size - the higher impedance stuff you can measure. You can just connect it without a probe with a short wire.
There could be no match from mains powered or big oscilloscopes.

No currents from a mains PS,
no antena effects, no
noise picked up from a probe.
Multiply this by 1mV sensitivity!

Perfect!

Try to connect a ferrite inductance between the ground and tip of the probe to act as an antenna (like I showed a few posts back) approach it to smps ps, chargers, etc and you're able to clearly see the control chip working even without opening the case, and with the advantage of no emi noise injected by mains power like almost happens with bench scope specially if you're in places with lots of electrical noises and bad ground connections. You also can view injectors cycle on automobile work without direct connecting it to the harnesses. I have others small cheap scopes and none work like this. My guess is this one being a true real time sample one, just my guess.

[Serg65536]

I have others small cheap scopes and none work like this. My guess is this one being a true real time sample one, just my guess.

Yes, that's high sensitivity + reliable and fast trigger + real time sampling + high acquisition rate.

The best device in such a form factor and price!

[Atlan]

I would have liked a 7-inch screen, this is too small. Yes, it's fine for a pocket, but it needed a screen for control and display.

[0xdeadbeef]

This scope is really good at measuring differential voltages inside a circuit.

Sure, you can do that - with one channel - and it's still somewhat problematic. A scope running from a battery is not the same as an isolated scope.
If the ground of the scope is actually on a high level, the bare metal metal BNC connectors are a safety hazard.

Yes, that's high sensitivity + reliable and fast trigger + real time sampling + high acquisition rate.

Well, a scope without a "reliable" trigger is not a scope. Not sure what a "fast" trigger is. A trigger is a trigger. And again, the trigger system is about as basic as can be.
Side note: there is no trigger jitter specified. Actually, I couldn't find any specification for the accuracy of the time base, either.
"Real time sampling" is something that every normal scope does. Most modern scope also perform some kind of "equivalent time base sampling" for cyclic signals (and if the real time sample rate is not sufficient), but that doesn't change the fact that they are real-time sampling scopes.
And about the "high acquisition rate": again there is no (maximum) number specified for waveforms/s. Most modern scopes sit somewhere between 50k and 1 Million, so if I had to guess, the DsTouch scopes would be more on the low end of this.
But sure, the DS4T252 is probably better than most offerings in the ~100€ range. But this is mainly because most of them are total garbage or outdated.
Still, the form factor is the most interesting feature but also kinda limits the actual use cases. Fiddling around on such a small screen is problematic, protocol decoding is nearly useless due to the screen size, the limitation to two channels and the lacking trigger options.
I fear that even though it's kinda cool, I would mainly buy it to buy it but would rarely actually use it.

[ptluis]

Checking frequency of an old Toyocom TCO 64.000MHz. Just straight connection to the output. Haven't build the test circuit on datasheet.

The sample rate is exactly 200MS/s measured with cursors.

Spot on!

[0xdeadbeef]

Hm.

[ptluis]

Hm.
(Attachment Link)

What you mean by Hm? do you have any doubts?
I have these modules for many years maybe 20 or more and they are surprisingly accurate today. The same with Citizen ones. And this scope is really competent in measuring frequency. The one on the photo is still exactly 64.000MHz and is one of the modules I use for testing.
This is Made in Japan not those Chinese crap ones

[0xdeadbeef]

The data sheet seems to define the frequency stability as +/- 100ppm. That would be worse than any normal XTAL and make it pointless as frequency standard.
But maybe I'm reading it the wrong way.

[ptluis]

The data sheet seems to define the frequency stability as +/- 100ppm. That would be worse than any normal XTAL and make it pointless as frequency standard.
But maybe I'm reading it the wrong way.

The frequency stability of a TCO in ppm indicates the maximum acceptable deviation of its output frequency from its nominal frequency over a specified period or range of environmental conditions. But it's not mandatory that a deviation must exist at a certain temperature range for example, i always test it between 22-24 degrees C and compare it with my Siglent before any testing. And as you probably know Japan make the best modules, they are known for their precision/stability that's why they're expensive. Besides what will be my purpose in deceiving results? I'm just showing why I like this scope.

[0xdeadbeef]

And still, the absolute deviation is unclear. Even a OCXO trimmer with a GPSDO has some frequency error.
Besides, "64,000MHz" could means a few hundred Hz deviation. Which still would be a pretty low deviation, but most probably not "spot on".
E.g. 64000444Hz would also be displayed as 64,000MHz and it still would be a (rather good, but not great) 7ppm deviation.
Anyway, given that they brag about using an "EPSON high-precision low-temperature drift crystal oscillator", they could have specified the time base stability/accuracy in the data sheet.

[ptluis]

And still, the absolute deviation is unclear. Even a OCXO trimmer with a GPSDO has some frequency error.
Besides, "64,000MHz" could means a few hundred Hz deviation. Which still would be a pretty low deviation, but most probably not "spot on".
E.g. 64000444Hz would also be displayed as 64,000MHz and it still would be a (rather good, but not great) 7ppm deviation.
Anyway, given that they brag about using an "EPSON high-precision low-temperature drift crystal oscillator", they could have specified the time base stability/accuracy in the data sheet.

The DS4T252 its a 5 digit Frequency measurement on MHz scale meaning when you try to measure frequency on a MHz signal you can only get info down to KHz. In case of the 64.000MHz module with +-100ppm, the deviation accepted is +-6400Hz, meaning  Minimum frequency: 63,993,600 Hz
Maximum frequency: 64,006,400 Hz
so this module is within specs, so in perfect condition.

One of the features I asked DreamSourcelabs to add is a frequency counter.

[tol]

Hi, I've read the thread but I couldn't find any posts about how to open the device to replace the battery. Some people write that the enclosure is glued. Can it be opened without damaging it? After 3-5 years of use, when the battery finally dies, there may appear more interesting models and some people would prefer to buy a new oscilloscope rather than replace the battery, but still, I think many people would like to replace the battery instead of buying a new device, especially the owners of the more expensive DS4T1012 model.

And yet another question, is it worth overpaying for DS4T1012 for home and hobby use, or DS4T252 is more than enough? I've read the thread and some people write that the DS4T252 sensitivity is 1mV/DIV with hundreds  mVolts of noise, so I couldn't understand what's the use of such a sensitivity with such a high level of noise, when the noise will not allow to see the little amplitude signals anyway.  Does DS4T1012 also have such a noise? If it doesn't have such a noise, the 10mV/DIV of "clean" output may be even more preferable than 1mV/DIV of "dirty" output to find weak signals. Or if I don't understand something, please clarify.

[ptluis]

Hi, I've read the thread but I couldn't find any posts about how to open the device to replace the battery. Some people write that the enclosure is glued. Can it be opened without damaging it? After 3-5 years of use, when the battery finally dies, there may appear more interesting models and some people would prefer to buy a new oscilloscope rather than replace the battery, but still, I think many people would like to replace the battery instead of buying a new device, especially the owners of the more expensive DS4T1012 model.

And yet another question, is it worth overpaying for DS4T1012 for home and hobby use, or DS4T252 is more than enough? I've read the thread and some people write that the DS4T252 sensitivity is 1mV/DIV with hundreds  mVolts of noise, so I couldn't understand what's the use of such a sensitivity with such a high level of noise, when the noise will not allow to see the little amplitude signals anyway.  Does DS4T1012 also have such a noise? If it doesn't have such a noise, the 10mV/DIV of "clean" output may be even more preferable than 1mV/DIV of "dirty" output to find weak signals. Or if I don't understand something, please clarify.

To open the device search on YouTube for Kerry Wong video on the DS4T1012 he show and explain how to do it.

The differences between DS4T1012 vs DS4T252 are mainly bandwidth 150MHz vs 50MHz, sample rate 1GS/s vs 200MS/s, deep memory 16M vs 2M, vertical scale 10mV vs 1mV.  The functionality is the same, with the same results.

Regarding measuring mV signals, a few posts back I posted a photo showing a 2mV sine wave captured with DS4T252 at 1mV/div.

What model should you choose? well it depends on what frequencies your working at. The DS4T1012 is way more expensive and price close to a better rich features Bench scope like the new Owon ADS800A series or the Rigol DHO800 series.

One correction the noise floor on 1mV/div is around hundreds uV (micro volts) not mV.

[tol]

One correction the noise floor on 1mV/div is around hundreds uV (micro volts) not mV.

When exactly 1mV/div may be useful in real life? I mean, when we deal with digital electronics, even +/- 0.2 Volts in the signal doesn't make difference in most cases, and many chips don't care of 0.8 V difference, so I'm not sure if this 1mV/div sensitivity with 50Mhz is better than 10mV/div with 150MHz, although I don't need it either Just want to find out what model is the most useful for its price. 200MS/s is rumored to be not enough for 2 channels. I've got Zoyi ZT-703s and it has (kind of) 280MS/s, and it also seems to be not enough for its (kind of) 50Mhz bandwidth.