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The I and Q bars will be useful, but caution on the 100% amplitude saturated color bars. It is not possible to modulate them linearly on the RF, because the peaks of the chroma represent 33 percent over-modulation; this is why later bar generators went to 75% amplitude bars. The over-modulation affects both the RF modulator in the generator, and the envelope detector in the receiver, particularly on the yellow and cyan bars, in unpredictable ways. The NTSC standard was set up this way to make the chroma signal less noisy, under the premise that these high levels would seldom be reached with real picture signals.
If you are going to use color bars through the tuner input to check the matrix in a CT-100, for example, you should use the 75% bars and adjust for rectangular waves of 75% amplitude compared to the 100% white bar. If your set has been jeeped to add a composite baseband video signal input, the 100% bar video can be used there without problems.
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