FNIRSI-1013D "100MHz" tablet oscilloscope

[Evi]

Цитата: pcprogrammer Сегодня в 08:25:25>What happens when you have the SD card in the scope and power it on?

Just normal start in stock FW

[pcprogrammer]

Sorry can't read Russian

But the fact that it starts the stock firmware means it does not see the correct boot header on the SD card. Why I don't know, because at a quick glance it looks ok in your hex listing.

[Evi]

I guess something wrong with the card structure

[pcprogrammer]

The fact that the stock firmware starts without errors means that the card works. The scope would fail with a "SD error" message when the card is not formatted correctly. You can see this by removing the card and then start the scope.

Without hands on it is very difficult to address these kind of problems.

[Sleo]

So, the question is:
are there kind enougth people, who can make card image from his Scope and upload here.

 Try this one. Done with Rufus based on mine 16 GB card, previously created with dd. I also tried to use HxD with no success.

[Evi]

Bingo!
I write image to 8Gb card until error. Then cancel.
Everything works!


Side effect: card did not recognized by PC.

[mobby_6kl]

You might look at the DSO2512G:

https://www.aliexpress.us/item/3256802899439203.html

Recent eevblog discussion:

https://www.eevblog.com/forum/testgear/new-2ch-pocket-dsosg-sigpeak-dso2512g/msg4506109/#msg4506109

Note that the video output is PAL not NTSC so you won't get color on NTSC monitors.

The Adrian Black video is here:

4/12 This $57 portable oscilloscope has a really cool feature (ZEEWEII DSO1511G review)
https://youtu.be/Uqrel5fQpK4

Adrian talks about the PAL/NTSC issue at 43:30.

Thanks, this is what I ended up going with. Seems like both reasonably cheap and useful enough, and if I end up getting a real bench scope later, it would be a useful portable tool thus minimizing "waste" Let's see.

[Evi]

Writing to 16Gb card gives full functional.
So, the technique have a rights to live.

[Evi]

The 2.5V bias on the input ground terminals is infuriating.
I suppose adding a -2.5V source to power the input OPAMPs would not be difficult.

[pcprogrammer]

Yep, but modifying it won't be easy.

Here is the schematic for the input part https://github.com/pecostm32/FNIRSI-1013D-1014D-Hack/blob/main/Schematics/Scope_Analog_Input.png

The 2.5V reference voltage you mention is only 1.25V, and is used throughout the design. To improve on it you would have to rip out the whole front end and create your own. It is not worth it in my opinion, because the rest of the sampling system is also crap.

[Evi]

Did it quick and dirty. The most painful operation was cutting grounds at OPAMPs.

The offset solution is not perfect, but it works.

The test signal is now displayed with the correct ground level.

[Evi]

Improved variant

[Evi]

Somewhere in this thread already mentioned the ability to switch the firmware.
I have automated the process.
The circuit is plugged between 3.3V and SD card supply pin.

[Evi]

Final and most stable offset Mod.

[dimorlus]

Is there a way to update software under Windows, possible on a SD card in a card reader? Maybe there is a ready SD image for win32diskimager-1.0.0?

[Sleo]

See reply #1480 on November 15, 2022, higher on this page. Image of 16 GB SD card made with Rufus.

[pcprogrammer]

I added the file to the firmware repository.

[dimorlus]

Ok, firmware works with rufus image. But when I connect Ch1 to the Test signal of the oscilloscope and press "Auto set" button, I see that both channels start to jump in vertical direction. It depends of the sync level, if there is no synchronization channels are not jumps. With the original SD card all ok.

[pcprogrammer]

Did you use the calibration function first?

[dimorlus]

Did you use the calibration function first?

After calibration shaking of the both channels (connected to the "Test 1kHz" only CH1) become less, but didn't disappear.

[pcprogrammer]

Well it is free and open source and comes as it is. You can always revert to the original firmware.

[dimorlus]

Sure, in any case, thanks a lot.

[illiac4]

Hi. Today i have turned on the the device and after few moments the screen turned off. Now it does not power on at all. It was not measuring anything when it turned off. Any clue what could be wrong?

TNX

[pcprogrammer]

Dead battery, voltage regulator, etc. It can be a lot of things that are at fault. You will have to open it up and measure voltages.

Take a look here: https://www.eevblog.com/forum/testgear/fnirsi-1013d-as-much-use-as-a-chocolate-fireguard/
That one still works but faulty. There are pointers on measuring the voltages in that thread.

[illiac4]

TNX it helped a lot. BAT is ok on MIC29302 3.3V pin i have 1,92V. I have injected 3.3v on that pin and it has turned on. I have measured on the same chip input and it is BAT input but output is 1,92. So i assume that the MIC29302 is defect. Will order replacement chips.