recently manage to get hold of a dunco enlarger. I believe it is the color head, it has 2 knob on the left adjusting exposure and on/off filter and 3 knobs at the right adjusting cyan magenta and yellow.

everything seems to be in order, but when I am doing some test strip, I doesnt seems to be getting any contrast when I am printing on multi grade paper. I have tried various method,
- adjust magenta and yellow on the enlarger
- switching everything off on the enlarger and use the ilford multi grade filter method
but all my prints turn out the same with no contrast.

I couldnt figure out what could have gone wrong. will need to consult all the expert here. I am hoping that it is just some minor stuff that I miss out or did wrong.