FT757.1 PK 232 TO YAESU 757GX YAESU 757 PK232 PIN 5 -------- PIN 4 PIN 6 -------- PIN 5 PIN 7 -------- SHIELD AROUND AUDIO LINE PIN 8..NC ON PK232 END PIN 8 -------- PIN 2 RX AUDIO CENTER PIN TO PIN 1 OF PK232 AND SHELL TO PIN 4..M. PHONE PLUG TO PLUG INTO EXT. SPEAKER OF 757