Update the firmware of Hantek2D72/2D42/2C72/2C42

Fred2C72 · Post time 2021-10-30 13:40:28

Hello everybody. Can anybody here help me fix the problem with my Hanteck DSO 2C72?

Here is the situation. When I use it the first time i bouht it, it works without any problem. Then for one month more or less i did not use it. Then it comes a time again that i need to use it on my work but to my surprise my 2C72 scope is not behaving as it should be. To cut the story short, here is the summary fault i found.
1. Generator Out(Square Wave Output) = No Output.
2. Coupling ( booth channel 1 and 2 acts the same).
a. AC Coupling = The trace always go to TOP of the screen.
b. DC Coupling = The trace still goes to the TOP of the screen.
c. GND Coupling = The trace goes to the Center of the screen.
I just want to add also that if i switch on the measurement, i get some measurement even though i did not connect any probe on the scope. For example if i set the channel 1 V/D to 1x with the reference set at the center, i get a reading of 5.000V. if i change the V/D to 10x i get 50.00V reading, if i set to 100x i get 500.0v and so on. If i set the coupling to GND,the trace goes to the center and the voltage measurement goes to 0.0000v which i think is correct.

Here is my System Info
Model: Hantek2C72
Soft: 2020070701
PCB: 0000000001
FPGA: V07

I hope somebody here is able to help me fix my scope problem. I am an electronics technician but i'm not familiar with the circuitry of an oscilloscope specially the front end.
PS: I did try reprogramming also the scope but that didn't fix the problem.

Thanks for your help.

Fred2C72 · Post time 2021-11-14 14:02:36

Fred2C72 replied at 2021-10-30 13:40
Hello everybody. Can anybody here help me fix the problem with my Hanteck DSO 2C72?

Here is the sit ...

Anybody here able to help me with this problem please...

Fred2C72 · Post time 2021-12-20 16:22:18

Edited by Fred2C72 at 2021-12-20 17:02

WITGIT7 replied at 2021-12-7 12:05
Your firmware is old.
Check this out.http://hantek.com/en/ProductDetail_1_13174.html

Thank you so much for your response sir.. i will try to update my oscilloscope firmware and i report back what will be the outcome.

Update: I have already updated my oscilloscope firmare to the latest version. But the problem still persist. If i try to calibrate,nothing happens. It says calibrating, but you cannot hear any clicking relay.
When i bought this the first time, if i calibrate this i hear a clicking relay, but now no more relay clicking. So i think this is really a hardware issue.

Fred2C72 · Post time 2021-12-20 16:24:01

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 ...

Mine is 2C72 sir.. Do you think it will cause issue if i update to the latest version?

Fred2C72 · Post time 2021-12-20 16:30:30

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.

Fred2C72 · Post time 2021-12-23 16:33:04

amy replied at 2021-12-23 13:35
Test the voltage at these points after the oscilloscope is turned on.

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?

Fred2C72 · Post time 2021-12-23 16:47:14

Edited by Fred2C72 at 2021-12-23 16:57

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.

Fred2C72 · Post time 2021-12-24 10:28:56

Thank you sir..i will update again after i replace the chip. hopefully it will fix the problem. thank you for your help.

Fred2C72 · Post time 2021-12-24 13:21:45

Edited by Fred2C72 at 2022-3-22 17:30

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.

Fred2C72 · Post time 2022-4-16 10:17:38

amy replied at 2021-12-23 13:35
Test the voltage at these points after the oscilloscope is turned on.

After waiting for a very long long time for my order from Aliexpress to arrived(Ordered = January 6, Received = April 16) I've finally fixed my poor oscilloscope by replacing the chip with a code"LTRA".
TP Voltages
1. +5V = +4.9V
2. -5V = -3.7V
3. +3.3V = +2.9V

Thank you so much sir for providing me the TP voltage, I've managed to find the faulty components. I hope it will last long this time because it's not easy to buy a replacement chip here in my place.