Ok first off you should get a service manual as they really do not cost that much.. Yes I totally agree with you that your set most likely needs a good cleaning and some minor adjustments. Please get the service manual. This will show you or explain to you exactly how the set comes apart and how to do an electrical focus alighnment as well as cleaning the set. You should not ever have to do an optical focus unless the set gets dropped or someone messes with the optic. Please refrain from adjusting the lens, as if you do mess with them you could mess up the outer parameter focus as well as the spot focus. good luck and let us know how this turns out for you.
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