I found a link to a procedure to refocus a 3-CRT rear-projection TV, and I wonder if it will work from the front controls of my TV?
Wow, what a dinosaur! I found one online that sold at auction for $5.00!
From the photo of the control panel you sent, you can display an internally generated crosshatch pattern, which is necessary to make any adjustments. There are recessed set-screws to adjust something horizontal and vertical in the red and blue CRTs so they coincide with the green, but I don't know if they adjust position or zoom. Also, I assume you can adjust the focus of the CRTs directly on the lenses. The procedure you found online does not look all that helpful for your situation.
But even at its best, this thing is no match for even a mediocre modern flat panel. The screen is 4:3 with a compound curve and probably very high gain, so there's only one viewing location that's going to look any good at alland it's never going to look very good compared with modern TVs. Honestly, unless you're a serious gearhead who enjoys fiddling with old equipment, I wouldn't waste my time.
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