[old_tv_nut]

The waveform you are getting looks like very distorted NTSC color bars to me (maybe clipped and inverted). Are you using NTSC color bars?

If so, maybe your fine tuning is off or you are actually tuned to the wrong channel. There is no color subcarrier showing, which could be caused by this.

The scope vertical setting specified is curiously low, as .02 V/div would indicate about a 0.1 v p-p video signal is expected at TP A7. This may be correct (I don't know), but many video circuits use a video level around 1 V p-p.