Hantek DSO2C15 about 37kHz impulse signal problem

figiel

I have big problem with impulse switch signal, about 37kHz on every measurement which should be free from it.
Looking for the source of the interfering signal first I check it in my basement (place without any electric devices, separated via 25 cm of reinforced concrete), then I went to a professional laboratory.

Result: source of this switching about 37kHz signal is... your Hantek DSO2C15!!!
Signal disappears when I turned off your oscilloscope (controlled by other professional oscilloscope).
It seems that the converter in the oscilloscope power supply is the source of the problems.
Of course I tested original and several others oscilloscope probes.

Have you encountered this problem with this model?

pu6k1n

Look here https://4pda.to/forum/index.php?showtopic=1018961&st=4140

figiel

pu6k1n replied at 2024-1-20 06:04
Look here https://4pda.to/forum/index.php?showtopic=1018961&st=4140

Thank you - but I have difficulty reading russian.
Could you point specified page of this forum (over 200 pages)?

pu6k1n

The fact is that this frequency is generated by: 1. Switching power supply; 2. The converter powers the backlight of the LCD monitor.

pu6k1n

The first point can be eliminated by converting the switching power supply to a linear one; diagrams and photos are available on the specified forum. We cannot eliminate the second point. The root of your problem is probably a pulse source.

figiel

Thank you for your answer