increase the picture-stability DP70 projectors

To increase the picture-stability Rosbeek Techniek has rebuild some DP70 projectors. Tests with an stroboscope teaches us that the standard belt-drive construction introduced some modulation in the drive system of the projector-head. Besides this modulation is manual tapping extremely heavy caused by friction of the belts especially with tread up an 70mm film. With the use of a servo motor as direct drive described in the following pictures, tapping the projector is electrically as wel as manually much easier. Picture stability increases dramatically with the use of a servo motor of course in combination with perfect adjustment of the complete projector head.