First let me say sorry I don't have a quick fix for this problem.
The problem you are describing is a very common one in CRT projection sets like yours. The convergence circuit has failed and will require component replacement in order to get the set working again. This repair should be done by a qualified technician, these sets can be dangerous to someone who does not know where not to touch, also it is very easy to cause more bad than good if you don't know what you are doing. Also the use of a digital multi meter and the ability to solder very well will be required. I cannot stress enough, you must be able to solder very well or can cause many problems.
If you have a meter and solder equipment and would like to complete this repair yourself please let me know and I will give you instructions on how to complete this repair. Parts can cost you anywhere from $50-$150 depending on where you buy them at. But remember I have seen quite a few people destroy perfectly good sets by not knowing what they are doing so just take that as a caution.
A good repair shop will run you somewhere between $300-$500 to repair this for you.
Let me first give you the warning: If you decide to repair this set yourself you will need to be careful, this set feeds the tubes with tens of thousands of volts and if you are not careful and do not know exactly what you are doing you can be hurt. There are also many different caps in the set that hold a charge and can hurt you as well. In addition I have seen many good people destroy their sets because they did not know what they were doing and either broke a circuit board or damaged some traces causing their sets to never work again. If you decide to go forward please take your time and if you are ever not sure on something please stop and ask me! Its better to take a day or two more to fix your set rather than destroy it
If you would like any additional information or have more questions please don't hesitate to ask!
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