Analog Code:FIC_02RV2.0_2-wire loop reverse battery signaling/ loop closure from customer/ reverse battery from LEC/ 600 ohms. Used for PBX-E911 trunks.*
Digital Code:FIC_04DU9.1KN_4-wire 1.544 Mbps (DS1) with Extended Super Frame
EUT STD:TIA-4965_Receive volume control requirements for digital and analog wireline handset terminals