PURPOSE: To increase the controllability of the TV camera as well as to extend the life time of the pickup tube by changing the TV camera from the pre-heating state to the full action state via operation of the channel selection switch of the TV picture receiver.

CONSTITUTION: The camera device consists of TV camera 1, multi-core cable 2, power source part 3, coaxial cable 4, TV picture receiver 5, antenna 6 and others. In this constitution, the low voltage is supplied to camera 1 from part 3, and thus the video signal is supplied to part 3 from camera 1 to be then sent to the idle channel of receiver 5 via RF converter 16. The DC voltage of rectifier circuit 13 is supplied to the heater of pickup tube 10 and full load 8 from cable 2 via relay 12 to actuate camera 1. When relay 12 has the adverse action, only the pre-heating voltage of the heater of tube 10 is supplied from constant voltage circuit 9 to secure the pre-heating state for camera 1. On the other hand, the signals from antenna 6 and converter 16 are switched via channel selection switches 21, 23 and 25 within receiver 5. Relay driving circuit 15 operates only when switch 21 is on to receive the image of camera 1.