CTC-5 21AXP22 convergence

[old_tv_nut]

Well, today I redid the purity and convergence from scratch again, starting with the edge magnets fully retracted (as before). The purity is now 100% better than before (still some white field non-uniformity), and the convergence has got a bit worse in the NE and SW corners. All in all, the color picture now looks much better.

I've got a another observation: off-channel, the snow and audio noise is very weak, and the AGC is cranked to max gain without getting any tearing or distortion. Is this normal for the Super chassis, or should I go looking for weak tuner/IF tubes? If I could get more signal out of the detector, it would help the generally weak drive that this chassis has. Have not put a scope on it yet to see what's actually there.

[Penthode]

The Super and Deluxe share the same tuner, video IF and luminance amplifier. If the agc is cranked to maximum and overload is not reached and you confirm a good level RF input, gain must be lost somewhere.

My CTC5 had low gain which simply was a bad 3rd VIF tube.

Even though my set had a quiet previous life, I found the video IF alignment off. A touch up further increased gain.

I now find the agc control set about mid-point. Cranking it up further sends it to overload.