[kaltarrr]

I'm looking for instruction manual for Pentax-F 28-80/3.5-4.5.
If somebody has one or knows where I can get it - please help.

[Dangermouse]

I don't think Pentax deliver manuals with lenses? What do you need to know?

I have that lens (non-SMC version) and it operates just like any other Pentax AF zoom. Only difference in operation between it and the newer DA lenses is that you need to make sure the aperture ring is set to A (press the small red button to allow you to turn it that far) in order for the camera body to control the aperture.

If you're using it with an older Pentax then pressing the same button will allow you to set the aperture manually - it basically functions to lock the lens in Auto mode.