The MSM301 is an accessory to the MS301. When connected by its single cable, it adds 3 more circuits, for a total of 6, to the MS301. The new circuits have all the functions of the original three, and are operated in the same manner. The MSM301 is powered by the MS301 and so does not add extra power to the system. It does allow the operator to communicate independently with three more circuits. Because each circuit of the MS301 and the MSM301 are capable of being either intercom or IFB channels, the need for a whole separate IFB system may be eliminated. The MSM301 occupies one rack space.

• Powered by MS301 to which it is attached
• Does not increase amount of current available, only the number of independent communications circuits
• The Status Bar of LEDs indicates that the unit is receiving its 24 volt operating current from the MS301 (green), and the trouble status of any of the circuits (red)
• On the rear panel there are DIP switches to allow you to choose between ducking and muting the program audio in the IFB mode, and for lifting the termination circuit of each circuit individually
• The MSM301 automatically maintains the 200W termination impedance when linking, but there may be applications where one of its circuits is connected differently