New oscilloscope from Fnirsi DPOS350P

[onefabis]

A big request to the programmers at fnirsi who worked on this device: completely redesign the spectrum analyzer block—it doesn't perform its functions at all! This is completely unacceptable! I don't understand why bloggers partially approved this feature. At frequencies of hundreds of kilohertz, the peak detection error is tens of kilohertz!
At least create an FFT function in this mode as a replacement for your spectrum analyzer—after all, you managed to display this function correctly in oscilloscope mode. Move the program code to spectrum analyzer mode.
What does it even show in this mode? We see hills.

Developer is here, his nickname is yangyao. Simply send him PM with your setup, use case and results. Nothing more, just: setup -> steps to reproduce measurements -> spectrum analyzer errors.

[ptluis]

A big request to the programmers at fnirsi who worked on this device: completely redesign the spectrum analyzer block—it doesn't perform its functions at all! This is completely unacceptable! I don't understand why bloggers partially approved this feature. At frequencies of hundreds of kilohertz, the peak detection error is tens of kilohertz!
At least create an FFT function in this mode as a replacement for your spectrum analyzer—after all, you managed to display this function correctly in oscilloscope mode. Move the program code to spectrum analyzer mode.
What does it even show in this mode? We see hills.

Bloggers are sponsored by brands so they won't speak the truth. Only independent ones that bought the equipment from their own pocket are able to give a real and true opinion. My experience with fnirsi is that you get what you see, if errors do exist you have to accept them and keep living your life. Or the best and recommend solution is to return it. That's what I did. I bought it mainly for the FRA but once I realized that the FRA and Spectrum analyzer don't operate properly, I return the joke ASAP. The more returns they get the better, maybe they realize that buyers are tired of being lied.
Also don't expect a new firmware because dpos350p was already abandoned and it was assumed by the developer. They are designing new decoration toys.

But not all is bad with fnirsi, some devices are decent ones, but not the scopes, they are too expensive. They should cut the price of dpos350p to around 70 bucks, that's a fair price for the quality of the unfinished, incorrect functions, and enough for nice graphics and basic operation.

[onefabis]

but not the scopes, they are too expensive. They should cut the price of dpos350p to around 70 bucks, that's a fair price for the quality of the unfinished, incorrect functions, and enough for nice graphics and basic operation.

Could you name any scope that has similar form-factor? I mean tablet-like scope with 6-10inch touch screen? I know Micsig, but their tablet scopes are really expensive. Anything else in similar price? I bought DPOS350P in 200 bucks, but I can't find something similar from other brands. I already have 55 bucks Richmeters 703S (ZOYI), but this one is not a tablet-like scope. Rigol DHO800? It's bigger than DPOS350P for me, however it has so much features and have 12 bit ADC, big memory, android. But its launch time and size... It should be somewhere in a lab environment even if it smaller than my Hantek dso2d15. So what's your alternatives?  Even ALIENTEK DM40B(C) with 3.5 touch screen costs about 100 bucks with much less bandwith and samples

[ptluis]

but not the scopes, they are too expensive. They should cut the price of dpos350p to around 70 bucks, that's a fair price for the quality of the unfinished, incorrect functions, and enough for nice graphics and basic operation.

Could you name any scope that has similar form-factor? I mean tablet-like scope with 6-10inch touch screen? I know Micsig, but their tablet scopes are really expensive. Anything else in similar price? I bought DPOS350P in 200 bucks, but I can't find something similar from other brands. I already have 55 bucks Richmeters 703S (ZOYI), but this one is not a tablet-like scope. Rigol DHO800? It's bigger than DPOS350P for me, however it has so much features and have 12 bit ADC, big memory, android. But its launch time and size... It should be somewhere in a lab environment even if it smaller than my Hantek dso2d15. So what's your alternatives?  Even ALIENTEK DM40B(C) with 3.5 touch screen costs about 100 bucks with much less bandwith and samples

Well, it depends on your intended use for an oscilloscope. Let me put it this way: what do you prefer:
1. An ugly oscilloscope that displays real signals and does what it promises.
2. A beautiful oscilloscope that displays incoherent information, making you, the user, doubt your own capabilities because you simply can't understand the information displayed?

 I know Fnirsi has people reading this forum, and all the criticism I post is aimed at them to wake up and fix the damn functions.

 It's unfortunate that a product like the dpos350p had such a focused promotion on the FRA and the Spectrum Analyzer, and then they sell the product with bugs making those functions useless when they are easy to fix, and they only don't do so because they're lazy.

If no one complains and the products aren't returned, they'll never release fixes. If all buyers accept defective products, Fnirsi will continue releasing more defective products without worrying about the equipment's proper functionality.  I'll buy a dpos350p again the day they fix all the bugs mentioned in this thread. Until then, they can keep them, as I prefer a device with less functionality but one I can trust.

Recently I bought a ds4t252 from dreamsourcelab, it doesn't have FRA or dedicated spectrum analyzer, but it has a functional fft, its surprisingly accurate, it has decoding, 2M deep memory (against not real 64k on dpos350p), holdoff trigger and most important developers continue to work on improvements. it costs around 100€. Is it for you? well I don't know because only you know your needs.

[onefabis]

1. An ugly oscilloscope that displays real signals and does what it promises...

Recently I bought a ds4t252 from dreamsourcelab...

Looking at the ds4t252, yeah, UI is really ugly. What the hell is this?

I hate that ugly fonts that ruin all UI experience in most "translated" devices that mostly developed for a China market, not a worldwide. 50 MHz bandwidth, 4.3 inch screen with pixelated font... Hmmm...

As I remember in my Hantek dso2d15 was FFT presented as well, never used it because its features showed that this was a joke from Hantek. As for FRA, I'm using 0404 E-MU (it's enough for me to measure audio devices), I think this is enough for me. Don't understand why scope developers put everything in this device. I'll be glad if Fnirsi developer will fix FRA and Spectrum analyzer in a future, but even without that I don't think it will be worse, allowing to measure oscilloscope data

[csuhi17]

but not the scopes, they are too expensive. They should cut the price of dpos350p to around 70 bucks, that's a fair price for the quality of the unfinished, incorrect functions, and enough for nice graphics and basic operation.

Could you name any scope that has similar form-factor? I mean tablet-like scope with 6-10inch touch screen?

Micsig VATO2004.
And you can attach a tablet as big as you want

[onefabis]

Micsig VATO2004.

It's twice expensive than DPOS350P and I need to find a tablet for that device and 12v power supply. And that's portable solution? Are you serious?
Come on, guys. Tablet-like device with not so tiny (3-5 inch) touch screen that will not cost more than 200$?

[ptluis]

1. An ugly oscilloscope that displays real signals and does what it promises...

Recently I bought a ds4t252 from dreamsourcelab...

Looking at the ds4t252, yeah, UI is really ugly. What the hell is this?
(Attachment Link)
I hate that ugly fonts that ruin all UI experience in most "translated" devices that mostly developed for a China market, not a worldwide. 50 MHz bandwidth, 4.3 inch screen with pixelated font... Hmmm...

I see, then what you need is option 2, a beautiful oscilloscope 

[ptluis]

Micsig VATO2004.

It's twice expensive than DPOS350P and I need to find a tablet for that device and 12v power supply. And that's portable solution? Are you serious?
Come on, guys. Tablet-like device with not so tiny (3-5 inch) touch screen that will not cost more than 200$?

You're wrong, VATO2004 includes an internal battery if you choose to.You really want to convince yourself and others that dpos350p at 200 bucks is a beautiful and wonderful piece of equipment. On the one I bought and return ASAP those lights on the side are horrible, the fan crazy loud, the measurements not stable and out of reality, the frequency counter short precision (try measuring 33.465843 MHz and you'll see the precision), etc, etc, but because it's tablet format, battery operated, etc and only 240 bucks you think it's a good buy?  but the important things, meaning working functions, precision, doesn't matter? so go ahead keep it or buy it. Your decision. My opinion on this device is based on the unit I bought paid with my own money so I give my real opinion.

Regarding the ds4t252 his software is different, some find it ugly, others different, or others good looking, his concept is 3 touch operation and what matters is that I can trust in the information displayed, put it in my pocket, use it anywhere up to 6 hours or more, silent, doesn't overheat, etc and if you want 150MHz bandwidth you have ds4t1012 model.

 Since you got a dpos350p try triggering an AM sine wave signal carrier 10MHz, mod sine wave 300Hz at 80%, then you see what you bought for 200 bucks.

[Mahagam]

I see, then what you need is option 2, a beautiful oscilloscope 

Let me fix it:
I see, then what you need is option 2, a beautiful toy, looking like oscilloscope 

[csuhi17]

I often wonder how and what other people use their oscilloscopes for.

The Fnirsi pushes the limits of sampling, measuring a 350MHz wave with 950 MSa/s.
The accuracy of the measurements is questionable, but it's up to everyone to decide how much precision they expect from it.
Is 2% enough or 0.001% necessary in all kinds of ways.

I only expect what they write in the manual from a cheap device.
But the Fnirsi often lies about its parameters... I'm used to it, I've already used three scopes from them. Now I'm going to play around with the 2C53P again to see if I can figure something out with the new firmware...

The trigger functions are so basic, basic edge trigger and nothing else...

The users don't use them or don't know that there are "holdoff" "PulseWidth" "N Edge" "TimeOut" etc. functions?!

For the display settings, to be able to turn off interpolation, or dot mode or straight line.
Persistence function that works properly. So that I can set the time like the big ones.

Pass/Fail function?!

The measurements are also the same for all Fnrisi scope, but it hasn't improved since the first version, there is no time measurement between channels, etc.

According to the manual of the newer 2D15P have some new, there are already a few calculation measurements in it, but there are no phase between waves etc.
It also has other features what is a big plus.

If you take 350MHz out of the description and replace it with the real 95MHz.
And you take that into account
A basic oscilloscope, with inaccurate measurements and unreliable bugs that most likely haven't been discovered yet.
Without a lot of simple but useful functions!

The ridiculous spectrum analyzer function.

Just like a working FRA function.

So far the best signal generator I've seen in a Fnrisi product.

And the Tablet format

Is it worth 200 USD to you? Although I can buy it for 300 USD... This is the cheapest to me...

The VATO would have been 370 USD, or there was a place where it was 270, I don't know why it's so much cheaper.
+ tablet for 50 USD is expensive or use your phone?!

How do you use the scope, like the analog one and that's all, don't you use its digital capabilities or are those functions so pointless and would it just be a waste of resources?!

People keep saying how cheap it is, but if you add everything up, it turns out that it's not cheap but expensive.

Owon TAO is twice as expensive at 600 USD, but its features are light years ahead, even though it's a much older device, it's much more reliable.

This is also true for the Micsig, but it has fewer features.

What you pay for and what you get is not a good ratio with the Fnrisi scope.
And this is valid if the device works without fatal errors.
I mean that it randomly freezes and sometimes the settings get stuck, for example, I set the channel to DC coupling but in reality it stays on AC. I'm looking for where the error is...

But the fact that the measurements are sometimes good and sometimes bad is unacceptable.
I know how much and in which direction my Owon handheld scope can only measure and I take this into account when using it.
But if it randomly breaks down, then it can't be calculated.

But if you use it as an Analog scope, Fnirsi is a good to buy.

[onefabis]

Since you got a dpos350p try triggering an AM sine wave signal carrier 10MHz, mod sine wave 300Hz at 80%, then you see what you bought for 200 bucks.

Grandchuck already posted it here #500 message in this topic. So what's the point?

[PlainName]

I often wonder how and what other people use their oscilloscopes for.I often wonder how and what other people use their oscilloscopes for.

I have a decent one on the bench so something like this is for when I am out and about, probably trying to figure out why the electric gates aren't working (again!). As such, I'm not so much interested in absolute accuracy. Just knowing it is more or less 5V would be enough, and seeing interference on a power rail without knowing how many nV it is would be fine. Of course, at some point I might need to know that stuff, but then I have Micsig which will measure all that. It's just that the Micsig is a bit too big and heavy to cart around unless necessary.

The FRA not being super accurate wouldn't be a problem since I would most probably want to know things are occurring in the right range or it's not happening. I think typical issues would fall into that scenario - in the field it's more likely that something isn't happening rather than that it happens but at slightly the wrong frequency or voltage or whatever.

OTOH, I do need reasonable trigger functions in order to make sense of the noise which is otherwise on the screen.

So, in theory, this scope might be suitable for me since it would meet most of my requirements for that kind of usage (and, as I say, I have better kit if it turns out I need better features). But the price is to high for the requirements, I think. And Fnirsi have lost me as a customer through their throw-away product philosophy where the only way to fix bugs is to buy a new product with its own bugs.

Sure, I am a sucker for great looking toys, but $200 is too much to leave on a shelf.

[csuhi17]

If you just need a few quick checks, there is a smaller pocket scope for that.

I had the Sigpeak, but I'm really sad that I lost it.
It was a good little scope, I could test almost everything with it.

If you don't use extra functions, just the basics, then an Owon multimeter, the HDS160, might be enough.
But there are other brands with similar designs that are better than the Owon.

[PlainName]

I am currently using a Zoyi ZT-703S. Not perfect but great for the price and does what I need.

[onefabis]

the frequency counter short precision (try measuring 33.465843 MHz and you'll see the precision), etc, etc...

Done! So what's the problem here?

[PlainName]

Output is 1V, display is 1.15V ?

[ptluis]

Since you got a dpos350p try triggering an AM sine wave signal carrier 10MHz, mod sine wave 300Hz at 80%, then you see what you bought for 200 bucks.

Grandchuck already posted it here #500 message in this topic. So what's the point?

Some of the points are:
The ugly can trigger the signal, the beautiful can NOT
The ugly can do proper FFT, the beautiful can NOT
The ugly can decode I2C, UART, SPI, the beautiful can NOT
The ugly have 1mV vertical scale, the beautiful NOT
The ugly have 2M memory depth, the beautiful NOT

the beautiful has FRA but useless, unstable, wrong phase implementation, values are always woobling, we never know what's the truth.... its a joke!

The Spectrum analyzer another joke seems like we're in the atlantic ocean, I had to take a pill against sea sick, The SA capture lots of noise, display fake harmonics not existent in the input signal, again a complete joke!
But hey! its beautiful! Colourful

The point is: Useful vs useless that's the point!

[ptluis]

the frequency counter short precision (try measuring 33.465843 MHz and you'll see the precision), etc, etc...

Done! So what's the problem here?
(Attachment Link)

Limited frequency counter, different voltage amplitude since it was commented previously

[onefabis]

Output is 1V, display is 1.15V ?

Yes, it was captured with it's own probe. Do you know that it isn't the best one, right? Here is my own probe, even it is not the best one, it's better than the kit one. I don't know what China (especially portable one) scope could do reliable voltage measurements on all voltages and frequency values. Even if you test in a lab with good generator, good probes, noise free environment, what do you expect to see on a real device with different elements with different resistance, are you really sure that you'll have 50 Om termination on the wire while you connecting the scope probe? What you can rely on? 

Limited frequency counter

What's the limit are you talking about? Do you want to see more digits aftre the dot symbol in the frequency counter, or something else?

The ugly have 1mV vertical scale, the beautiful NOT

DPOS350P have 2mV vertical scale, do you really need it?

[ptluis]

Limited frequency counter

What's the limit are you talking about? I want to see more digits aftre the dot symbol in the frequency counter, or something else?

You can't really check a TCXO frequency with only two digits after the dot or a crystal resonance frequency. You can only guess or do the math manually.

[Grandchuck]

Output is 1V, display is 1.15V ?

Yes, it was captured with it's own probe. Do you know that it isn't the best one, right? Here is my own probe, even it is not the best one, it's better than the kit one. I don't know what China (especially portable one) scope could do reliable voltage measurements on all voltages and frequency values. Even if you test in a lab with good generator, good probes, noise free environment, what do you expect to see on a real device with different elements with different resistance, are you really sure that you'll have 50 Om termination on the wire while you connecting the scope probe? What you can rely on? 

I set up the Fnirsi generator for 1 Vpp squarewave and took some measurements with the Fnirsi and with a SDS2000X HD as shown in the table below.  No probes were used.  When I do use probes with the Fnirsi, I do not use the ones it shipped with.

[BillyO]

You can't really check a TCXO frequency with only two digits after the dot or a crystal resonance frequency. You can only guess or do the math manually.

It's a toy oscilloscope.  If you need to accurately check a TCXO to 8 digits I'd recommend a good frequency counter with a GPSDO reference.  You might get a good used HP  53132A and a GPSDO for around $700 if you look hard enough.  Accurate frequency counters are not cheap and it is unrealistic to expect one in a toy scope.

[onefabis]

Yeah, I don't understand how that gradually changed: First, Chinese device manufacturers got users used to the idea that a measuring instrument should be affordable and cheap. Then they got them used to the idea that an oscilloscope should do everything well: 3-in-1, make coffee, and even clean the apartment Then they pushed the idea that these devices can also be accurate. That last point I don’t believe, because professional equipment must go through calibration (I don't mean that magic button on the screen) and certification, and certainly shouldn’t be measured "on the fly" with some unmatched probes.

[PlainName]

If we want to be really picky, the 33.46 in the display should be 33.47 since .xx5 should round up, not down