Please note that you do the cleaning at your own risk!

Because the (webcam) lens has been removed the CCD is no longer continuously protected against dust, and when bright objects (sun, moon, planets) the dust particles on the sensor show up as ugly big blobs.

First: PREVENT that the CCD gets dirty

CLEANING the CCD: I have (alas) done this often so I have some expertise ....

I experimented with Pritt Poster Buddies - a kind of adhesive gum - as I had read that others had successfully used Blu Tack to pick up dust particles from the surface of the CCD, but with disappointing results: Pritt Poster Buddies leaves small particles behind, and that is exactly what we do not want.
So I will continue to use Q-tips !

How to clean the CCD of the ATK16IC camera

Please note that you do the cleaning at your own risk
and that opening the camera might void the warranty!

A closer look at the CCD of the ATK16IC camera, which is protected by optical glass against dust. Should any dust migrate behind the optical glass just remove the ring holding the optical glass and turn the camera upside down, gently tap on the backside of the camera and the optical glass will fall out (so be careful !!).
Now you can reach the CCD; to clean I use Q-tips and my clip-on magnifier for visual inspection.
More about sensor cleaning [the interesting stuff starts on page 11 ...]
Steve Chambers recommends: To test the 16IC you could use a M42 thread camera lens stopped to f16; you can use it in daylight: just aim it at a plain surface (wall, paper etc).

I found out that while imaging the Sun with my PST and ATK16IC combo the 'donuts' are very nicely visible on the Preview screen. And of course the results of a cleaning operation can immediately be verified: it is nice to be able do this it in daylight :o)