allright, guys. Made a recalibration with 1x. 1st channel still overcompensated on 2v/div(20v/div old calibration), 2nd channel still perfect.
in attachment result with 1x probe and 1kHz signal. I think that cap wich is parallel to trimmer cap 2(as in manual) is too small. Who knows wich type of caps using there?
May I ask why you mess with this oscilloscope probe factor. This have nothing to do here. When you are doing this front end internal adjustments do not mess with probe factor at all. (do not also mix it with probe head 1x/10x switch - this is other thing.
If you set oscilloscope 10x and set vertical adjustemnt to 20V/div it is exactly same as you set oscilloscope for 1x and and vertical setting 2V/div. Only what change is oscilloscope voltage level number.
For adjust oscilloscope attenuators LF compensation trimmers just follow instructions. Set oscilloscope probe factor for 1x and keep it.
Connect coaxial cable from signal generator output BNC directly to oscilloscope input BNC (in this case we do not need input normalizer). Also if your signal generator produce very fast square wave edges then need take care about ringing, but if it is typical slow edge "10-20MHz grade" function generator no need extra care - this is not rocket science).
Select 200mV/div. Set signal generator for 1.2V p-p square wave and frequency 10kHz. After then adjust trimmer (look instructions what trimmer) for perfect flat top and bottom, exactly. After then adjust signal generator level for 12Vp-p square and same frequency. Set Vertical level for 2V/div. Now adjust this other trimmer for perfect flat bottom and top square. Exactly. Then check these both again and do some fine adjust if need. Iterate so many times result is perfect. After then same for other channel.
After then do self calibration and
nothing connected to input BNC's.
After then if you use probes and example use oscilloscope 1kHz probe calibration signal. Set probe to 10x and oscilloscope probe setting also to 10x. In this point you adjust only probe head compensation trimmer for as perfect flat square as you can (it drift very easy!). And in this point if you are not satisfied this square wave do not touch oscilloscope internal adjustments for correction. Probe is probe and these are cheap not high class probes) If you now touch these you do whole procedure again starting from scratch.
Oscilloscope internal front end attenuators adjustment trimmers must not adjust using probes! As tautech told, here need use coaxial cable from signal generator output BNC to oscilloscope input BNC.
(this model) Oscilloscope analog front end have three voltage ranges and two of these have own attenuator circuit (I use here only thes big 1-2-5 steps for simplify) And of course these numbers are when oscilloscope input is set for 1X
1. 500uV - 100mV/div (there is no attenuator what need adjust)
2. 200mV - 1V/div (this range have attenuator what have also LF compensation trimmer)
3. 2V - 10V/div (this range have attenuator what have also LF compensation trimmer)
If you use other input multiplier of course these numbers are different (this multiplier affect only to displayed numbers and nothing else.
Input multiplier is just for show right numbers. 1x multiplier and 2V/div and 10x multiplier and 20V/div is exactly same circuit inside oscilloscope without any kind of change. Only display number change.
If you set probe attenuation for 10x it meand that probe divide your voltage from probe tip to oscilloscope input 10:1
This is why you need set oscilloscope so that it multiply numbers 10x for show right voltage.
Voltage levels in instruction is levels in oscilloscope input BNC.
In case you use right adjustment methods ( signal generator with good flat top and bottom square wave and right adjustment procedure and can not still adjust square wave enough perfect then perhaps your capacitors (what you have soldered) are not ok or you have damaged some other things there. But first, try adjustment with right procedure
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