CTC-5 Westcott restoration

[SwizzyMan]

Holding at 230ma. Went to adjust it and the slug is frozen in the coil. How do I free it up without removing the chassis from the cabinet?

[old_coot88]

If 230 ma. is a correct reading it's gonna cook the H.out tube in short order. It ain't too easy on the flyback either.

[Electronic M]

You free the slug by trying to turn it while heating the coil with a heat gun or hair dryer, or if the lin coil wires are reasonably thick and your adventurous you could hook a "D" cell battery across the lin coil and let the battery heat it like I did successfully on my CTC-4. Wax melt is likely what is holding it.

[SwizzyMan]

The lowest I can get it is 220ma which is OK according to the service manual. What do you guys think?

[miniman82]

I think you can get it lower, but I also think it doesn't matter much on a 5. The flyback primary just doesn't have a low enough DC resistance to make much power (or heat), which is also the same reason it will never draw enough current to make decent HV at the secondary. Run it for a good half hour, then power down and check flyback temp with your hand after HV discharge. My guess, it won't even be warm to the touch. I did everything I could to mine trying to push more out of it: installed a drive control and cranked it to max, installed a HV pot and cranked it to max, put in the strongest testing 5U4 and 3A3 rectifiers I could find, nothing helped at all. Since you can't change the primary resistance in the flyback, the only other thing likely to help is increasing voltage to the circuit. You might try using silicon rectifiers in place of the 5U4's, but I still don't think it would make much difference. The 5 just is what it is, and we have to deal with it.

[SwizzyMan]

Originally Posted by miniman82

I think you can get it lower, but I also think it doesn't matter much on a 5. The flyback primary just doesn't have a low enough DC resistance to make much power (or heat), which is also the same reason it will never draw enough current to make decent HV at the secondary. Run it for a good half hour, then power down and check flyback temp with your hand after HV discharge. My guess, it won't even be warm to the touch. I did everything I could to mine trying to push more out of it: installed a drive control and cranked it to max, installed a HV pot and cranked it to max, put in the strongest testing 5U4 and 3A3 rectifiers I could find, nothing helped at all. Since you can't change the primary resistance in the flyback, the only other thing likely to help is increasing voltage to the circuit. You might try using silicon rectifiers in place of the 5U4's, but I still don't think it would make much difference. The 5 just is what it is, and we have to deal with it.

Got it down to 200ma by decreasing the line voltage by 2 volts to 113 or so. Still pushing about 21.45 Kv nice and bright. I think it is ready for service.

[SwizzyMan]

Here is the finished product. My camera makes the picture look a bit washed out in some photos. It is perfect in person though. And there is a picture of me with the TV after we just picked it up.

[Username1]

Looks good ! That's the way I got mine home too !

.

[SwizzyMan]

Not quite satisfied with the color temperature. While trying to do a proper temperature setup I ran into some difficulties. The manual says to turn the green and blue background controls 30% up from being at counter clockwise. And to turn the contrast control to the halfway position. I know what all this means but how could I tell where 30% is on the screen controls and where halfway on the contrast control is?

[Radiotronman]

That looks great! It's inspired me to start my ctc9 very soon!

[old_tv_nut]

Originally Posted by SwizzyMan

Not quite satisfied with the color temperature. While trying to do a proper temperature setup I ran into some difficulties. The manual says to turn the green and blue background controls 30% up from being at counter clockwise. And to turn the contrast control to the halfway position. I know what all this means but how could I tell where 30% is on the screen controls and where halfway on the contrast control is?

They are asking to set mechanically at a certain fraction of full travel (which should be somewhat less than a full circle max). So, just try the full mechanical range to see how far the control can turn and then set it an estimated halfway or 30% of the way as instructed. These are just starting points to get you somewhere with visible light on the screen.

[old_coot88]

When our shop entered the color market with the CTC-15, we went to 'RCA School' put on by the distributor, where we learned setup procedure from factory reps. They
had us do the whole procedure with both the blue and green Drives at max . Then as a final touchup, back either one (or both) down a bit to get desired 'temp'. The reps may have been "off the book" regarding the Drives, but that's the way we leart it and always did it.

Or, book procedures on earlier chassies may have been different.

In those screen shots of you CTC-5 running, it looks like the contrast is a mite low.

[SwizzyMan]

Did what you suggested old coot. Picture looks a lot better. Only problem is that the chroma hue drifts while the set warms up for 10 minutes then goes away but still very very slowly drifts. The contrast is no longer an issue here. The camera caused the bit of washed outness if you will.

[dtvmcdonald]

Dave's is the correct saturation, the picture is just too blue.

But to all of you with these old TVs, let me admonish you,

PLEASE!! PLEASE!!!

One word!

Doilies!!!

[Electronic M]

Originally Posted by dtvmcdonald

Dave's is the correct saturation, the picture is just too blue.

But to all of you with these old TVs, let me admonish you,

PLEASE!! PLEASE!!!

One word!

Doilies!!!

Doilies are for old ladies! If you want to protect the finish of the cabinet top get a piece of glass cut to match the size and shape of the top and glue some small thin felt pads to the side of the glass that will be resting on the cabinet (one at each corner)....It is much better at preventing scratches and water marks, was used on fine furniture of the period, and looks 300% cooler.