A pickup system includes CCD 25 driven by different frequencies. Each of the CCD 25 can be driven with a predetermined frequency even by using an attachable/detachable camera head or an electronic endoscopy. Furthermore, a signal processing clock of a video processing circuit 29 can be processed by one type of clock. The drive signal of the predetermined frequency supplied to the CCD is generated via an oscillation circuit CXO 155, a frequency divider circuit 132, and a timing generator T.G 131 in the video processing circuit 29. A CCD signal output from the CCD 25 is supplied to a line memory 139 in a floating circuit 135. The write-in clock WCK of the line memory 139 used has been divided into a frequency corresponding to the CCD 25 used in the frequency divider circuit 132. The read-out clock RCK of one frequency is used regardless of the CCD 25 used. Thus, signal processing in a secondary circuit 136 after the line memory 139 can always be processed by a common oscillation clock.