jack is to be fitted the socket 11 is integrally formed with a socket mount 11b as shown in fig2 b the cabinet 9 is integrally formed with a boss 9a when mounting the socket 11 on the cabinet 9 the socket mount 11b is fixed to the boss 9a by a bolt 13 while the fixed shaft 11a of the socket 11 is fitted into the hole 12 a holding member 14 in the socket 11 has a mechanical structure which is similar to the earphone jack for holding an earphone plug and a terminal 15 projects outwardly of the socket 11 an antenna terminal board 16 is provided and a conductive member 17 such as a lead wire or metal member has its one end fixed to the terminal 15 by soldering or the like a bolt 18 is provided for electrically connecting the other end of the conductive member 17 and the antenna terminal board 16 and for fixing the conductive member 17 and the antenna terminal board 16 to the cabinet 9 with the above construction by inserting the base of the resin cover 1 into the recess 10 of the cabinet 9 the antenna body can be held by the cabinet 9 simultaneously the plug pin 3 is inserted into the socket 11 to contact the holding member 14 in this manner the plug pin 3 is electrically connected to the antenna terminal board 16 through.