RCA CTC-5 Deluxe Chandler Restoration

[Penthode]

Originally Posted by trinescope

My 5, although basically working, could probably use a wholesale replacement of the carbon resistors, since I've already had so many of them that were either off value when I started, or have gone bad over time and caused new problems. My HV probe is a Fluke, and the kind used with an external DMM, and seems to be accurate. The big issue is how the HV just drops off suddenly if the brightness control is advanced too far, and, according to others here on this board, is a normal characteristic of the CTC5. In any case, IMO, the 5 really isn't a good "daily driver" because of the weak HV supply and the fact it just isn't very bright with the original AXP tube, not to mention convergence drift with the DC static adjustments instead of the magnets everything else used.

I use the CTC5 regularly and it delivers excellent color pictures. The Deluxe Chassis has wider bandwidth Chroma demodulation so it provides a bit more color detail.

The HV drooping issue was a concern which was mainly addressed by selecting a new horizontal output tube and replacing the vacuum tube HV rectifier with a solid state replacement.

Two issues I see is the dimness of the 21AXP22 which is overcome watching the set in a darkened room. The other is poorish black level clamping which I feel may have been exacerbated by the contrast control modification.However I do not see it any worse than subsequent chassis's CTC7, CTC9 etc.