These type of problems are typical of a CRT monitor in need of service. Sooner or later every CRT arcade monitor will require some level of maintenance. And, probably again and again. It is just the nature of the obsolete CRT monitor.
Whenever I service a CRT monitor, I perform a complete overhaul. So, not only do I fix the immediate problem, but I also do the things that will help the monitor to run trouble free for some time to come.
My complete monitor overhaul includes at least the following, and more if required:
1. Repair of the immediate monitor problem.
2. Replacement of the capacitors. There are about 20 capacitors that with age will negatively affect the performance of any CRT monitor. This is a proactive measure that will keep the monitor looking good.
3. Clean the monitor of all dust. Due to their electro-magnetic fields, CRT monitors really are dust magnets. Dust traps heat and shortens the life of electronic components. I use high pressure air to get the monitor as clean as is possible.
4. Rejuvenate the picture tube. Rejuvenation will help make the CRT monitor's images look almost like new.
5. Inspect and repair all solder joints. Over time, the heat produced by the natural resistance of solder will degrade a solder joint to the point that it is no longer conductive. Thus, an open in the circuit will occur, and the CRT monitor will fail.
6. Adjust to specification the colors, brightness, contrast, and image heigth and width to improve the appearance, but mainly to increase the life of the CRT monitor. And,
7. Degauss the CRT monitor. As a final touch, I degauss the monitor with a degaussing coil. This procedure purifies the colors.
The overhauled CRT monitor will look almost as it did when it was brand new (except for any screen burn-in). And, should perform trouble free for some time to come. Plus, the overhaul comes with a 30-day full parts and labor warranty.
To avoid all the above problems and expense, you might consider upgrading to an LCD/LED monitor.
Email me now for a cost estimate to overhaul or replace your obsolete CRT monitor: firstname.lastname@example.org