JK Audio Four IFB - Manual (Page 7)

7
Quick Setup Guide (continued)
11. To drop a call, rotate the Monitor selector switch to the
desired Line position. Line 1 = phone line connected to
the RJ-11 marked Line 1.
Press the Drop button.
This will drop (hang up)
the call on the selected
line. The corresponding
Line LED will go dark.
12. After use, be sure to turn off the power switch.
The battery will lose charge if the power switch is left
on and there is no AC power source present, even if
the unit is not in use.