Title: Problem with HANTEK 6254BD. Large DC offset and unable to self calibrate [Print this page] Author: atsirigotis Time: 2018-6-13 14:03 Title: Problem with HANTEK 6254BD. Large DC offset and unable to self calibrate Dear Sir
I have purchased a HANTEK 6254BD USB oscilloscope and it has some problems that I don't know how to solve.
The first problem is that it has a DC offset on all channels. I see the offset when I connect it to the square pulse generator pins (probe compensator).
This happens not only when I use the probe compensator, but it also happens when I connect the channel to the function generator of the oscilloscope (using a T-connector with a 50ohm termination).
The most strange thing is that the offset changes (more or less randomly) when I change the vertical position. This is most annoying since I cannot use vertical scale below 50mV. The waveforms disappears above the upper edge of the screen.
I tried to self calibrate (this the second problem), but when I start a self calibration it never ends even after several hours (even after 6 hours).
Is the oscilloscope faulty? Or it needs a firmware update? Or I use an outdated software version?
Thanks for your time
Author: wolferl Time: 2018-6-13 18:14
same with my 6254BD - self calibration never stops... Author: atsirigotis Time: 2018-6-15 14:12
Update for the problem.
It seems that all the problems were created by the drivers. Before I was using a Windows 7 PC.
When I used a Windows 10 PC all worked properly.
However it seems that the oscilloscope offset is very temperature dependent.
Moreover, I would suggest an external power source (2A USB charger), if you are going to use it with a laptop.
Last, but not least, is there anyone that knows the format of the .drc files?
I have a very general idea of the waveform record format:
A 172 bytes header (unknown), then a 8200 bytes record per waveform per channel. Each record has each own header of 8 bytes (unknown).
The remaining 4096 words (2 bytes each) are the samples. The first byte of each word is the 8bit ADC count, while (I think) that the second byte has something to do with the data validity.