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MSM301 Master Station Expansion Module for MS301

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MSRP: $999.99
(You save $50.00 )

MS301 Independent Communications Circuit Expander Module

The MSM301 attaches to an MS301 to double the number of available independent circuits from 3 to 6. The new circuits: D, E & F have all the capabilities of the original 3, including program audio insertion and control and the ability to use each circuit as either intercom or IFB with program muting or ducking. Connection of the two units is via D-Sub connector and the short cable is supplied with the MSM301. As with the original 3 circuits, each of the new circuits has 2 XLRs on the rear for connecting stations. The number of stations connected any of these XLRs can be further increased by the use of an SB1 accessory.

Key Features

  • 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


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