Author Topic: FNIRSI-1013D "100MHz" tablet oscilloscope (Read 428284 times)

gadak · « **Reply #2100 on:** March 13, 2024, 09:22:27 am »

Calibration went without errors. Autoset mode underestimates real voltage values

gadak · « **Reply #2101 on:** March 13, 2024, 10:08:36 am »

Try the following manipulations, set the voltage, for example 13 volts and connect to the first and second channel of the oscilloscope, press autoset and see how the second channel will react. The marker of the second channel rises to the very top, and there is no possibility to sign it on the screen. Only by disconnecting the voltage from the noise of the second channel and pressing autoset again, the situation stabilizes and the marker goes down to the initial position. If you re-apply voltage to the second channel and do not press autoset, then the voltage value is measured correctly.

Atlan · « **Reply #2102 on:** March 13, 2024, 10:57:13 am »

If the trigger is chosen for ch2. Does it behave the same?

engineer.r152 · « **Reply #2103 on:** March 13, 2024, 01:12:53 pm »

I confirm that there is such a problem with CH2, it behaves the same with the CH1 or CH2 trigger enabled

gadak · « **Reply #2104 on:** March 13, 2024, 01:49:52 pm »

It is not important to make any adjustments to the voltage range or sweep time. Channel two is not subject to any adjustment or modification.

Atlan · « **Reply #2105 on:** March 13, 2024, 03:10:12 pm »

Maybe I'll look at it tonight.

Just connect any DC voltage and press autoset?

Changing the trigger from ch1 to ch2 will not change the behavior of ch1. Ch2 is fine and ch1 moves the flow up?

Atlan · « **Reply #2106 on:** March 13, 2024, 08:32:05 pm »

test it. 0.024j

gadak · « **Reply #2107 on:** March 13, 2024, 10:42:53 pm »

Yes, just by connecting a DC voltage and pressing autoset.

gadak · « **Reply #2108 on:** March 13, 2024, 11:49:03 pm »

No problem on firmware 0.024j. I have a question why offset on the second channel is 16 and on the first channel -2 after calibration? But the difference between the real voltage values is 0.8 volts. The real value is set to 14 volts, for example, and after pressing autoset the oscilloscope shows 13.2 volts.

Atlan · « **Reply #2109 on:** March 14, 2024, 08:35:47 am »

During calibration, the offset should be 0, the offset changes only in DC mode after pressing autoset. The max and min values are measured, and the necessary signal shift is calculated from their difference. You have a lot of interference on channel 2. The fact that it has such a deviation must be due to that or a bad value in the program.

gadak · « **Reply #2110 on:** March 14, 2024, 09:32:54 am »

Maybe you can tell me how to reduce the interference on the second channel?

Atlan · « **Reply #2111 on:** March 14, 2024, 09:52:10 am »

The 13.2V is the value measured by the V-cursor or a number in the measurements.

_AVP_ · « **Reply #2112 on:** March 14, 2024, 02:44:54 pm »

FW0.024J - not correct touchscreen coordinates for choose probe mode (1x,10x,100x). They are upper, at "V/A mode". I think video is unnesessary. Also temperature on calibration screen displays as 99*
But there are very good news! Device starts 10/10 times without "SD Error" like on any FWs 21 and older. Do you remember I posted videos? I only updated FW without any other actions! Respect!

Atlan · « **Reply #2113 on:** March 14, 2024, 04:29:38 pm »

That's because it's a developed version.
The errors were important, so I preferred to fix them, even if the channel menu is not finished.

This firmware was not ready, and I forgot what modifications I had already made. I fixed the detected error when measuring in DC mode, so I recorded it, later the error with the shift of channel 2 was detected and it was somehow corrected.

gadak · « **Reply #2114 on:** March 15, 2024, 02:25:03 am »

This is the value of Vrms

tokar · « **Reply #2115 on:** March 18, 2024, 03:02:31 pm »

v0024j.
Calibration was carried out on the latest version (voltage source - battery):
300mV - 300.1
600mV - 600.2
1.5V - 1.498
3V - 3.001
7.5V - 7.500
15V - 15.04
-----------------------
I built a table and graph of the nonlinearity of an oscilloscope voltmeter. Maybe someone will be interested.

Atlan · « **Reply #2116 on:** March 18, 2024, 04:05:00 pm »

Yes, DC voltage calibration is done to the Vavg value. For the elimination of jumping values from the AD converter.

Atlan · « **Reply #2117 on:** March 20, 2024, 10:48:54 pm »

Fixed menu switching 1x - 100x
And some graphical improvements to the appearance. v0.024k

engineer.r152 · « **Reply #2118 on:** March 21, 2024, 05:39:57 am »

It would be great to display the value in amperes in the cursor menu when switching to current mode.

Atlan · « **Reply #2119 on:** March 21, 2024, 07:30:09 am »

V/A is not functional. DO NOT USE. There are still many things to be done.

tokar · « **Reply #2120 on:** March 21, 2024, 10:07:45 am »

https://youtu.be/q6wImOeBrfY
The autoset does not work correctly when selecting the operating frequency and period.
In the video the frequency is 1MHZ, you can see collisions and incorrect frequency meter readings.
This happens at any frequency and signal shape.

Atlan · « **Reply #2121 on:** March 21, 2024, 11:18:58 am »

If peak to peak is less than 1V (rms 350mV) then it does not work. I'll look into it.

tokar · « **Reply #2122 on:** March 21, 2024, 12:49:19 pm »

I applied a 2v RMS square wave signal, the situation did not change.

Atlan · « **Reply #2123 on:** March 21, 2024, 04:47:34 pm »

I found the problem. I'll have to figure out how to fix it.

tokar · « **Reply #2124 on:** March 22, 2024, 05:54:39 am »

Yes, indeed, with a 1:1 divider and a signal above 350 mV RMS, auto-tuning in frequency and period begins to work more or less stably. Thanks to Atlan for the tips and improvements.


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Author Topic: FNIRSI-1013D "100MHz" tablet oscilloscope (Read 428284 times)

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