Hantek DSO5202P not working properly

Alx · Post time 2016-10-3 20:26:27

Edited by Alx at 2016-10-11 17:11

I recently purchased an DSO5202P oscilloscope.
I have tested it on 12V@150Hz, but it does not clearly show the square wave on the first channel.
I tested the same signal on both channels and on the second channel i saw the right square wave signal. On the 1-st channel signal is different - height of front is above the signal level and it exponentially lowering to the signal's back, the same situation on the back of signal but vise versa - it exponentially lowering to the zero. Probes were calibrated by the internal square wave(5V@1KHz). Looks like in has problem with vertical amplifier compensation on different frequencies because in internal square wave(5V@1KHz) it shows square signal in both channels, but in the 1-st channel level of sygnal is a bit lower. There was no matter of probes changing - no luck.
Give me some resolution. Please help.

Alexandr

Alx · Post time 2016-10-4 14:42:08

Если поменять пробники местами ничего не меняется.

Alx · Post time 2016-10-4 15:20:52

Да, измерил другой сигнал 12 вольт. Делители соответствуют и земля была подключена. Автокалибровку осцилографа запускал, длилась минут 5, после попробовал ещё раз - ничего не поменялось. Посоветуйте пожалуйста что делать, совсем новый осциллограф, а получается, что 1-м каналом пользоваться нельзя.

Alx · Post time 2016-10-4 15:35:03

Да скриншоты от сигнала 150Hz@12v. Ок, попробую изменить настройку подавление частоты свыше 20Mhz, очень надеюсь что в этом проблема. Завтра вам отпишу.

Alx · Post time 2016-10-6 19:48:00

The problem still exist. Hantek people, please give me some advice.

Alx · Post time 2016-10-11 14:34:01

The same signal. Pink is difference.

Alx · Post time 2016-10-11 17:10:47

Edited by Alx at 2016-10-11 17:17

Probes were adjusted in internal square wave(5V@1KHz) and shows right square wave. Only on 150Hz it shows wrong form of signal. And i switched probe from one channel to another - forms of signal didn't change.

Alx · Post time 2016-10-24 16:53:33

Just checked. The problem is only in Hz. In MHz and KHz it works fine.

Alx · Post time 2016-10-26 14:38:11

Do not understand what i should solder, could you explain?

Alx · Post time 2016-10-26 18:11:31

Edited by Alx at 2016-10-27 17:18

Could you give me links to datasheets for that components and places where i should replace it in scope?
I have found AQY280SX http://www.mouser.com/ds/2/316/panasonic_AQW,AQY280,282,284-347496.pdf is it correct?
Can't find what is U100.