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I would not go replacing caps following assumptions. THe problems you are facing are due to defective components, but you need to properly troubleshoot the set before you can come to a conclusion as to what part is really at fault. Do you have a schematic and a receiving tube manual? If so you can compare voltage readings on the tubes with what is in the schematic. If something is terribly wrong (ie 2v where it should be -10) it can be easily determined what is causing it. I can send you a scan of the IF and video sections of the CTC-16 chassis if you can give me an email address.
Unless you like throwing money at caps you may not need, you really need a good capacitance tester that measures leakage. Simple digital multimeters aren't good enough because they do not supply enough voltage to cause the suspect cap to malfunction. A real capacitance tester will put anywhere from 1-1000v through a cap to ensure there is no leakage. Sometimes you can use an old VTVM and use it on the AC function to measure leakage on a capacitor. An ESR meter is good as well, but only really for electrolytics and no for film mica, or ceramic caps.
The ceramic and films caps do not fail as often as electrolytics, but they do fail. If there is smearing on a black and white picture as well as color, I would look to video and IF circuits. YOu can take out the bandpass amp, color amp and 3.58 tubes to render the color circuits inoperative. This may better help you to isolate the video smearing problem.
The vertical shrinkage is attributable to drifting grid resistors on the vertical output tube, and faulty electrolytic (big silver can on the vertical board) As a precaution if I experience that shrinkage problem I will shotgun the board with all new caps and check the resistors on the board for drift. Its ok to see a slightly lower resistance than the printed value while in the circuit board. However, if the value taken is more than 10% of its actual printed value, the I will replace it.
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Jordan
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