Hameg HM 203 double trace problem

[BFX]

I'm not sure that IC201 is wrong. Here is photo.



The same signal on both chanels.
Only attu on channel 2 is set to 0.1V

[Andy Watson]

Looking pretty!

Should be easy to find the problem with channel 2 since you've got a working channel to compare it against.

[David Hess]

The leading edges do not look right to me.  The overshoot might exclude a probe compensation problem.

As subtle as that is it points to a major problem.

[BFX]

Ok boys, problem solved 

David Hess: yes it's probe compensation problem.

Here is some updates to solve major problem


And oscilloscope works well


Tomorow final calibration and testing .... and finish.

[BFX]

Here is some interim results of calibration.
I'm surprised form this, it's realy nice:)
I don't shorten parallel connection of resistors on input and it's beautiful to see to interference. 


from owon 8202


from hameg 203-1

It's measured on second corrected channel. It's same time base and same attenuator settings.

[David Hess]

So the overshoot was in the pulse generator.  That looks good to me.

[BFX]

yes it's my old homemade poor generator   
but in this case it is easy to see that the oscilloscope works very well

here is screenshot from scope (before I was lazy )