amy replied at 2021-12-9 09:24
Please try to perform self-calibration (Menu->Calibrate).
If the problem still cannot be solved, ...
I already performed a self calibration sir before i make a post here. I tried it several times, but every time i did a self calibration, the oscilloscope hang on a particular sequence and never finished the calibration. so i think it is really a hardware issue.
if anybody can provide a service manual or schematic i will try to locate the problematic components.
Its so sad that my oscilloscope didn't last that long. Its only more than a year since i bought it, and now it is not working.
WITGIT7 replied at 2021-12-8 14:26
However make sure to what you are updating.
It broke my 2D72. Stopped showing me the signal. Downgr ...
Hahaha that's because you don't know anything, I updated my 2D72 with the latest firmware and then I did a self-calibration and using the function generator that comes with the same oscilloscope I started testing and it works perfect, even now I can take out and add different measurement parameters in the measurement chart.
Thank you so much for trying to help me fix the problem sir. I really appreciate your help.
I will open again my scope sir and i will test that point you have given.
One note sir, maybe this will help you point me to the exact location of the problem. Right now the condition of the scope is,everytime i powered on, i did not hear any relay clicking. As far as i know when this scope is still working normal, everytime i powered it on, the relay clicks.
Do you think the relay is busted on my scope sir?
Update:
I measured the TP as per the photo sir and here is the result.
+5V TP = 4.929V
-5V TP = 0.196V
3V3 = 2.950V
This is the measurement sir with respect to Ground.
What is the name of the 5 pin chip responsible for generating the -5Volts supply? It has a marking code of LTRA on my scope sir. Maybe you can give some info on this chip.
I checked on Ali Express, but i was shocked on the shipping fee of the chip,,very expensive
Update:
I have ordered one on Ali Express,and you know what, shipping time is just crazy looooonngggggg... It will take 3 months before getting my order,hmmmm . But what can i do than to wait.
Hopefully i will receive my order soon and revived my poor handheld oscilloscope.
Update again on my order on AliExpress..
Sad to say,after waiting for 3 long months,i did not receive my order.. Maybe it was lost during transportation..hmmmm..i need to find another store to buy the parts.
It is not about how much I know or don't!!!! it doesn't show any line and get freeze. Doesn't measure and doesn't show the waves. All other FW works no issue what so ever. Your mindset needs to get calibrated before you get in conversation to respect others in logic!