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OpenHantek / OpenHantek6022

OpenHantek6022 is a DSO software for Hantek USB digital signal oscilloscopes 6022BE / BL. Development OS is Debian Linux, but the program also works on FreeBSD, MacOS, RaspberryPi and Windows. No support for non-Linux related issues unless a volunteer steps in!
GNU General Public License v3.0
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Offset on channel 1 with DSO-6022BL #104

Closed UweGo closed 4 years ago

UweGo commented 4 years ago

I have an offset error with DSO-6022BL (FW0207) and OpenHantek6022(3.1.1) on Linux. There is no offset error with Hantek software with Windows. I short-circuited the probes to ground and readout the DC offset with different settings. Channel1: 200mV x 10 = 600mV= 500mV x 10 = 600mV= 2V x 10 = 960mV= 5V x 10 = 1,92V= 10V x 10 = 2,83V= 20V x 10 = 2,83V= 50V x 10 = 2,83V= Channel 2 200mV x 10 = 278mV= 500mV x 10 = 278mV= 1V x 10 = 278mV= 2V x 10 = 388mV= 5V x 10 = 576mV= 10V x 10 = 297mV= 20V x 10 = 307mV= 50V x 10 = 299mV= There is no difference in this behavior if I plug the oscilloscope in from time to time. Compiled on Linux Manjaro Linux version 5.4.44-1-MANJARO (builduser@development)
AMD64 gcc-version 10.1.0 QT 5.12.0 MESA 20.0.7 Caicos [Radeon HD 6450/7450/8450 / R5 230 OEM] Start message: qt5ct: using qt5ct plugin qt5ct: palette support is disabled qt5ct: D-Bus global menu: no

Channel 1 and channel 2 connected to GND. Openhantek_6022BL

Channel 1 connected to cal. output. Channel 2 connected to GND. OpenHantek_6200BL_2

Same settings as before with Hantek software on VM-Virtual-Box.

Hantek6022BE_VM-Ware-2

Ho-Ro commented 4 years ago

The Hantek DSO-6022Bx hardware has a quite big offset error due to the brain-dead HW design. Therefore it is necessary to calibrate the zero offset, the device provides a factory offset calibration in the EEPROM.

  1. Did you calibrate the scope before using it?
  2. Do you have a calibration file?
  3. What is the content of the scope's calibration EEPROM?
  4. Did you calibrate the Hantek software on VM-Virtual-Box?
UweGo commented 4 years ago

(4.) I didn't calibrate the Hantek software on VM-Virtual-Box before. It confused me. The original software didn't show an offset. (1.) I run this in a terminal: calibrate_6022.py -e Setting up scope...

Calculate zero adjustment Apply 0 V to both channels and press Measure offset at low speed for gain 10 Measure offset at high speed for gain 10 Measure offset at low speed for gain 5 Measure offset at high speed for gain 5 Measure offset at low speed for gain 2 Measure offset at high speed for gain 2 Measure offset at low speed for gain 1 Measure offset at high speed for gain 1 eeprom content [ 8 .. 39 ]: b'8f878f878f878c858a838781878187818f878f878f878c858982878087808780' eeprom content [ 40 .. 55 ]: b'ffffffffffffffffffffffffffffffff' eeprom content [ 56 .. 87 ]: b'837383738373cf613b618845884588456aff6aff6aff91ffb8ff80ff80ff80ff'

After that there is no zero offset with OpenHantek. A calibration button in the OpenHantek software would be great ;-)

sheerun commented 2 years ago

could you do calibration in client software instead of eeprom? it's cumbersome to update it

Ho-Ro commented 2 years ago

@sheerun: please check #189

sheerun commented 2 years ago

Thank you! Could you please put example .ini file in the readme as I can't easily run get_calibration.py on macos? I think I could write it manually

Ho-Ro commented 2 years ago

Please have a look at the issue #189, this comment provides some links to ini files.