TN1029 - MM400 Series Bead Chain/Lanyard Replacement

This kit includes those parts and instructions necessary to replace a broken or damaged battery cap retaining cable assembly on any existing MM400, MM400a or MM400b Transmitter. With the exception of the first illustration, only the MM400b transmitter is used; however, the same procedure applies to all transmitters in the MM400 series.

Parts included:

  • MM400b Replacement Kit
  • Replacement drive screws (3 each, Lectrosonics part number 28828)
  • Replacement spacing washers (3 each, Lectrosonics part number 28809)
  • Replacement cable lanyard (1 each, Lectrosonics part number 35900)
  • Instruction set
  • MM400 or MM400a Replacement Kit
  • Replacement drive screws (3 each, Lectrosonics part number 28807)
  • Replacement spacing washers (3 each, Lectrosonics part number 28809)
  • Replacement cable lanyard (1 each, Lectrosonics part number 35900-1)
  • Instruction set

Tools needed:

  • Vise grip pliers
  • Small Vise (or two vise grip pliers)

Procedure:

  1. Ensure the unit is turned off. If necessary, remove the antenna and microphone. Unscrew the Battery Cap,
    and remove and set aside the battery.

    tn1029-graphics-1
  2. While holding the case snuggly, use the vise grips to grip the screw head on the case and with a counter-clockwise twisting motion, gently pull the drive screw from the case. Discard the Drive Screw, but set aside the spacing washer. Use the same procedure to remove the Drive Screw on the MM400 or MM400A case.

    repdrvscrw-cu
  3. Hold the Battery Cap snugly, or use a small vise or a second pair of vise grips, and grip the Battery Cap drive screw. With a counter-clockwise twisting motion, gently remove the old drive screw from battery cap. Discard the Drive Screw, but set aside the spacing washer.

    repdrvscrw-cu
  4. Slide the new lanyard cable and spacing washer on the new Drive Screw, then use a pair of vice grips to press the new Drive Screw into the MM400B case until it stops. Be careful not to scratch the MM400B case. The drive screw should not seat completely; if it does, the lanyard may not rotate freely. If the lanyard binds, or does not turn freely, pull the drive screw out a small amount in the same manner as the drive screws were removed.

    Important: The spacing washer must be placed between the cable lanyard and the battery cap & case as shown to function correctly.

    repdrvscrwcap-cu
  5. Slide the new lanyard cable and spacing washer on another new Drive Screw, then use a pair of vice grips to press the new Drive Screw into the Battery Cap until it stops. Be careful not to damage the threads on the MM400B Battery Cap. As with the MM400B case, the drive screw should not seat completely; if it does, the lanyard may not rotate freely. If the lanyard binds, or does not turn freely, pull the drive screw out a small amount in the same manner as the drive screws were removed.

    Important: The spacing washer must be placed between the cable lanyard and the battery cap & case as shown to function correctly.

    mm400b-capdrive2
  6. Reinstall the battery, antenna and microphone. The unit is now ready to return to operation.