How do you fix the convergence on a big screen television?

Answer

Gosh! Big answer, but I'll give you the outline. I assume this is an old Barco-type 3 CRT projector with three lenses and tubes - one red, one green and one blue. If not, I'm not sure why the question is being asked.

Disclaimer: This is a tricky procedure that should ONLY be attempted by someone who has been trained to do this. You try this AT YOUR OWN RISK - both to the EQUIPMENT and to YOURSELF and others around you!

In outline, switch of red and blue (you will find gun switches on the control panel along with the other dozens of contrrols!)

Switch on the grid (there will be a "grid picture" generator built-in) then use first the static then the dynamic controls to get the grid as square and even as possible on the screen.

Next, add the red tube (gun). Using the static position controls first, get the centre of the grid to line up, then thebrest of the static controls to aligh the rest as best you can. Next use the synamic controls to adjust the linearity top, bottom, left right etc - and finally use the corner controls to get those aligned as well.

Turn off red, turn on blue (make sure the room is totally dark - seeing the blue alignment is always a problem). Do the same for the blue.

If you absolutely can't get the alignment right (and remember it changes with picture size and distance from the screen - so don't move it once you're done!) on some older projectors, there are "move the whole picure" controls on the necks of the tubes themselves. BE CAREFUL - you're playing with around 128,000 volts around there!

This might be useful . . . http://www.curtpalme.com/SetupDVD.shtm

Steve.

First answer by ID1483367046. Last edit by Bssohal. Contributor trust: 0 [recommend contributor]. Question popularity: 9 [recommend question]