that the power of the adapter 10 is inputted into the camcorder as the battery adapter mode signals batt ext of the low electric potential is applied to the battery adapter detection terminal p1 the central processing unit 17 recognizes the low electric potential of the battery adapter mode signals batt ext and judges whether or not the operation mode of the camcorder is terminated by the vcr control signals vc and the camera control signals cc which are inputted to the input terminal p6 as a result of the judgement if the operation mode is not terminated the central processing unit 17 outputs charge signals of the low electric potential to the base of the transistor q24 of the battery ground voltage output circuit 15 through the charge terminal p2 and thereafter the transistors q24 and q23 are turned off respectively so that the charge loop does not occur as a result of the judgement if the operation mode of the camcoder is terminated the first voltage output circuit 12 divides the battery voltage or the adapter voltage into the resistances r31 and r32 and outputs a predetermined voltage to the voltage detection terminal p3 of the central processing unit 17 thereafter the central processing unit 17 which generated the output of the first voltage circuit 12 judges whether or not the voltage acv of the adapter 10 is over 9 v if the result is over 9 v the central processing unit 17 outputs the low electric charge signals to the base of the transistor q24 of the battery ground voltage output circuit 15 through the charge terminal p2 thereafter the transistor q24 which receives the charge signals of the low electric potential which is applied to the base thereof.