PURPOSE: To ensure the free selection and application for a ribbon feeder of 300Ω or a coaxial cable of 75Ω through a switching operation of a changeover switch.

CONSTITUTION: With use of a ribbon feeder 22 of 300Ω, a changeover tongue bar 41 is turned to be connected to a fitting receiver 46. Thus the matching of impedance of 300Ω-75Ω is attained by the function of a balun 21. As a result, an external antenna is connected to a TV picture receiver. When a coaxial cable 27 of 75Ω is used, the bar 41 is turned to release the matching to a fitting receiver 45. Then a slotting hole 43 is turned to the inserting direction of the cable 27, and a core wire 27a is put through the hole 43 for connection. At the same time, a shielding wire 27b is held between the holder pieces 33 and 34. Thus the matching is attained for the impedance of 75Ω-75Ω without receiving the effect of the balun 21. In such way, an external antenna can be connected to a TV picture receiver.