[old_tv_nut]

I'd describe it as follows:

The CTC-5 does not have diodes to clamp the dynamic waveforms at the center like later sets, so in the CTC-5, points halfway between the center and edge stay motionless while the center moves the opposite of the edges. The trick is to rough in the DC in the center, then adjust the dynamics to get parallel R, G, and B lines, then fine tune the DC for best overall (and then maybe retweak the dynamic a tiny bit).

Hope your DC control pots are in good condition and not burned just at the proper setting point like mine were (both originals and replacements from a parts donor).

100 ohm carbon pot with tap at 25 ohms IIRC. Really pushing the limit on low total resistance for a carbon pot. I made up a substitution with 6 wirewound pots and three switches to pick a tap just above or just below or at the nominal tap point. If I was doing it again, I'd be tempted to try subbing a later cloverleaf with permanent magnet DC adjustments, but I don't know if the coils would be right for the dynamics.