CurtPalme.com Home Theater Forum

[gholt]

I have a Barco 800 that has been operating fine, but today I noticed that the red parts of the picture were fuzzy. I put up a grid and noticed that the lines, especially the horizontal lines, are thicker than usual on the red (only). I checked the mechanical focus to see if it could have been bumped, and couldn't improve the focus mechanically.

Before I go any further in messing around with the tube installation level focus procedures, is there something else that I should be checking?

Thanks in advance.

[Curt Palme]

Yes, check the electronic focus pot on the side of the set, on the same side as the blue tube. It's on the board with the yellow LEDs that light up when the set is powered up. The top three controls are focus, one for each tube, the bottom ones are the master brightness controls (don't touch those).

You should be able to dial in the focus with that control, and touch up the G and B as well.

If it drifts again, then that focus board is bad, the CRT socket is bad on the red, or the red tube is bad.

Cheers!

[Curt Palme]

Yes, check the electronic focus pot on the side of the set, on the same side as the blue tube. It's on the board with the yellow LEDs that light up when the set is powered up. The top three controls are focus, one for each tube, the bottom ones are the master brightness controls (don't touch those).

You should be able to dial in the focus with that control, and touch up the G and B as well.

If it drifts again, then that focus board is bad, the CRT socket is bad on the red, or the red tube is bad.

Cheers!

[gholt]

Thanks Curt. I should have thought of that! It worked perfectly, and the focus seems to be holding. Thanks again!