Abstract: A method and apparatus for operating a frequency division multiplexing (FDM) transmitter within a common communication channel is disclosed. The carrier frequency for each separate channel is adjusted for minimizing intermodulation interference. The system randomly allocates each separate channel within the available bandwidth to provide an initial set of separate channel allocation and corresponding carrier frequencies. Thereafter carrier to intermodulation ratio (C/IM) on each channel is measured and the worst channel with the lowest carrier to intermodulation ratio (C/IM) is removed. The system then repeatedly inserts a channel in available unoccupied bandwidth to produce the largest minimum carrier to intermodulation ratio (C/IM). The deletion and insertion continues until no improvement in minimum carrier to intermodulation ratio (C/IM) can be achieved for said random allocation of separate channels.

Abstract: A single integrated machine for editing, dubbing, mixing, transferring and resolving on and with a sound motion picture film. The machine contains a first two track audio tape section, a second two track audio tape section and a film transport section including an audio stripe read head. All three of these sections are mechanically coupled together to provide a frame by frame correspondence between audio tracks and film track. The audio tracks are all electronically coupled together to permit transferring of sound from any one audio track to any other audio track on a frame by frame basis. One of the audio tracks is used as a cue track to provide cue signals for the location of scenes and for the transfer of any portion of a scene from one audio track to another selected audio track.