Unfortunately wackymacs is right. You have killed something on that analog board, and possibly also damaged the crt (bright flashes emanating from within a crt are a very bad thing). Debugging that new problem (which is almost certainly more complex than the original one) on top of what you were already trying to do is asking a lot. You're better off getting another unit, and performing a transplant.

And if you need to solder anything in the future, please be sure to inspect your work very carefully before reapplying power. Haste is costly.