hantek dso5102p channel 2 not working

Qet

Good day, channel 2 on my scilliscope is not functionning properlly. Channel 2 on my oscilloscope is not functioning properly. It was very erratic and not measuring properly, some signal is getting through but the signal wave is very distorted, jittery and smaller/or or deformed of original signal.  I believe some components in channel 2 may be open or shorted.  I probed the signal at the inside of the bnc connector where it solders into the pcb and the signal is very small there even.  Can you give me some guidance on what components to check/relapse? I cannot find a service manual anywhere online. My oscilloscope is not 2 years old yet. Thank you very much. Thank you very much.

amy

Please input the same square wave to the two channels and compare the waveforms of the points at the same position of the two channels.If there is any abnormality, please upload some pictures to study.

Qet

Sorry it took so long for me to get back to you, Ive been very busy with school, I am uploading the test points for channel a and channel b for comparison.  the probes are set to X10 I am using a siglent  sds 1202x-e borrowed from a friend to take the measurements.
The following is channel A

Qet

Here is Channel B.  The pictures are uploaded in order with the test points.

amy

Sorry, I missed some information. Please input 600mVpp square wave to two channels of DSO5102P(probe ×1, volt/div of two channels is set to 100mV), and then compare and test the waveforms of the two channels at these five points.

Qet

I am sorry that I could not post again in such a  long time but I just wanted to let you know that I did find the issue, it was a open smt resistor on the board. All is ok now Amy. Thank you very much!!