This is quite a nice chip, and has myriad uses, but we only need it to perform one function here. Since most game systems output the composite sync information along with the NTSC video output, and since most RGB monitors will not accept this extraneous info along with the sync, we need to remove the video signal. The LM1881 does an admirable job of this. It's a dead easy circuit - one small chip, two small capacitors and a small resistor. As the below pic shows, it's small enough to wedge into a DB-9 hood.