An apparatus for maintaining tension of a transmission line in a tubular includes a first clamp segment configured to surround at least a portion of a transmission line and a second clamp segment configured to surround at least a portion of the transmission line. The second clamp segment has a first axial end and a second axial end. The first axial end is configured to contact an axial end of the first clamp segment, such that the first clamp segment and the second clamp segment are configured to apply a force in opposite radial directions to clamp the transmission line with respect to the tubular to lock a position of the transmission line with respect to the tubular.