JVC 330 Service Manual page 56

Chapter 2—Functional Descriptions
Figure 2-15 Video Processor Board, Block Diagram
Decoder
The optional decoder is a daughter board installed on the VPB. Since the VPB can
only operate on an RGB/sync signal, use of the decoder is necessary in order for
the projector to use a composite signal. The decoder takes a composite (NTSC,
PAL, or SECAM) or S-Vid input and converts it into an RGB Sync signal for
2-44 Model 330. 340SC, and 370SC Service Manual