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Once the raster looks good play with fine tuning and adjacent channels to see if you can get decent video strength and sound...
If the set uses intercarrier sound circuit topology, and has no video and weak sound and uses a germanium diode for a video detector that can be a symptom of it's failure.
If you have a purpose built RF and video test pattern generator and you can't get RF on any channel you can try injecting video at any plate or grid between the video detector and the CRT. If you don't have a purpose built generator, but do have a video source connect a pair of .1uF 600 volt caps in series with the hot and shield leads of the video source (to help prevent frying your source) cable and try injecting near the output of the video detector and first video amp stage.
Have you cleaned the tuner contacts?...If they are dirty they can prevent signal flow from getting past them.
Are you familiar with what a non horizontally and vertically synced picture looks like? ( horizontal and diagonal stripes)....it looks like garbage to the unfamiliar, but tweaking the hold controls (and sometimes coarse horizontal osc freq) will often get good picture out of an unsynchronized mess.
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