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Assuming the wiring to each stage is correct and the tubes are conducting and the tube dc voltages are present, then evaluating the IF alignment can begin. Replacing the capacitors and altering the wiring dressing, will dramatically affect the staggered tuning. There is a lot of gain in the VIF strip and if the tuning of two stages coincide, the strip will likely oscillate resulting in a total loss of picture.
To determine if the VIF is oscillating, measure the dc voltage across the detector load resistor with no signal input. There should be no DC (less than one volt DC). You need to test this first. Reducing the contrast control will increase the bias on the first stages (there is no AGC in the ts630). If the IF is indeed oscillating, you will reach a point the dc across the detector load will dramatically drop. It is important that the IF strip is not in oscillation before proceeding.
Next, rough alignment is first achieved by injecting a signal stage by stage and tuning each of the staggered stages to what is recommended. Then as each stage is tune to its recommended frequency, you would use the sweep generator to review the combined stagger tuned response.
Follow the RCA published data for the ts630 and it will say essentially the same thing.
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