[Penthode]

I created this new thread to discuss the video quality on a CTC5 I am in the process of restoring.

I have checked the RF/IF alignment and the response looks pretty good. But I am not satisfied with the picture quality. The picture looks soft. The scan focus is good and the CRT is bright without blooming.

The problem looks as if it may be the luma amplifier. There is no trace of any subcarrier getting into the luma channel (no characteristic dots)which suggests the frequency response must be rolling off pretty early. I adjusted the 4.5 MHz trap.

Perhaps it is the delay line? (No evidence of ringing). Or perhaps the peaking coils?

The service notes show the luma response rolling off after 2.5 MHz.

I am curious if others see the same on the CTC4, CTC5 or any color sets of that vintage? (I am referring to the post CT-100, 21CT55 sets).

Note: I have seen pretty sharp pictures on the CTC10 and CTC11 vintage sets. but not sets from the '50's.

Cheers, Terry