163 CONNECTION AND MAINTENANCE■ AntennaA key element in the performance of any communicationsystems is an antenna. Contact your dealer for more infor-mation regarding antennas and how to install them.■ Fuse replacementA fuse is installed in the supplied DC power cable. If a fuseblows or the transceiver stops functioning, track down thesource of the problem if possible, and then replace the dam-aged fuse with a new rated one.❑ Fuse rating: 10 AUSE the 10 A fuse only.■ CleaningIf the transceiver becomes dusty or dirty, wipe it clean with asoft, dry cloth.DO NOT use solvents such as benzene or alco-hol, as they may damage the transceiver surfaces.■ Options• OPC-1939 acc cableAllows you to connect to an external terminal.• HM-152/HM-152T/HM-148G/HM-148T hand microphoneHM-152 : Hand microphoneHM-152T : DTMF microphoneHM-148G : Self ground heavy duty microphoneHM-148T : Self ground heavy duty microphone with 10-keypadThe 10-keypad of this microphone can be used for theDTMF code transmission only.• SM-25 desktop microphone• SP-5/SP-10/SP-35 external speakerInput impedance : 4 øMaximum input power : 5 W (SP-5/SP-10) /7 W (SP-35)SP-5 : Large speaker for good audio quality.SP-10 : For all-round mobile operation.SP-35 : Compact and easy-to-install.• UT-108R dtmf decoder unitProvides pager and code squelch capabilities.• UT-109R/UT-110R scrambler unitsNon-rolling type (UT-109R)/Rolling type (UT-110R) voice scramblerunit provides higher communication security.