PURPOSE: To achieve excellent impedance matching, with a simple operation only by the replacement of an auxiliary cable having a capacitor at the terminal, when the frequency band of FM waves is changed.

CONSTITUTION: One end PA side of a cable main body 21 is connected to a main cable connected to an antenna via a jack 22. The other end PB side of the cable main body 21 is connected to a relay cable via a plug 23. Capacitors 24, 25 of small size equivalent to a capacitive open stub are connected to the jack 22 and the inside of the plug 23. Thus, excellent impedance matching can be obtained even if an FM frequency band changes, by changing the length of the auxiliary main body 21.