[old_tv_nut]

If it's any consolation, I have never been satisfied with the luma drive level on my CTC-5. It seems the chroma sections have much more capability. It's on my "some day" list to revisit this issue, but now that it's been brought up, maybe someone else here can comment.

One thought: check the AGC and make sure you have the proper video level at the video detector. Also try substituting video output tubes. In the Magnavox set I had, I found that the output tubes varied quite a bit and you could get more gain out of some than others. I think the luma channel is really pushing to get enough gain out of the final tube.