48 TO XK516D1 HF TRANSCEIVER (HF RECOMMENDED TRANSCEIVER). PN 964-0452-012. -042. OR -052: INSPECTION AND REPLACEMENT OF HIGH FREOUENCY (HF) MODEM NON-CONFORMING INTEGRATED CIRCUIT (VOICE BAND ANALOG INTERFACE). SERVICE BULLETIN MOS 05-N0V-2013 SB 965-0976-0XXX-34-38 . SERVICE BULLETIN R1 MOS - (s) SB A001-25-96 . SER