SETUP AND CONVERGENCE PROCEDURE
1.Use a knife to brake free the magnetic rings on the yoke, which are usually locked with red varnish. Bring the adjustment tabs on each pair of magnetic rings in line for the starting point.
2.Loosen the yoke clamp. Remove the yoke wedges and the tape from the CRT.
3.Connect a test generator to the video input.
4.Turn the monitor on. Switch the test generator to red field. Adjust the horizontal and vertical raster size, on the remote control board, for under scan. Let the monitor run for at least half an hour.
5.Check the auto bright control voltage with a DVM. Connect the DMM to GND and pin 8 of the LM324 920 on the video board. The voltage range is 4.0V to 4.4V. If out of range, adjust this voltage to 4.2V by using pliers to rotate the bottom knob on the FBT.
6.Degauss the picture tube and front part of the frame.
CAUTION: To avoid electrical shock,
take care not to touch the yoke conductors or push against the anode cap.
Always keep one hand free to avoid making a complete electrical circuit.
7.Adjust the yoke position, on the CRT neck, to the center of purity. One way to locate this yoke position is to make a felt pen mark on the CRT neck at the rear extreme of purity and another mark at the front extreme of purity. Make a third mark between the two marks and set the yoke to this position. Rotate the yoke to line up, the raster top line, with the top of the picture tube. Tighten the yoke clamp. Tilt the yoke side to side and up and down while watching the red field to verify that purity is good.
8.If the yoke position adjustment does not produce good purity, adjust the purity magnets. Tabs closest to the yoke winding.
9.Switch the generator to the red/blue grid. Adjust the 4 pole magnets (center pair)
for convergence of the red and blue guns in the center of the screen.
10.Tilt the yoke up and down for the best convergence around the edge of the grid. Insert the top yoke wedge. Tilt the yoke side to side for the best convergence around the edge of the grid and insert the rest of the yoke wedges. Secure the wedges with tape.
11.Switch the generator to the white grid. Adjust the 6 pole magnets (Pair closest to the video board) for convergence of the green gun. Step #10 and this step may have to be repeated for optimum convergence.
12.If the corner convergence is still not acceptable, shunts may be used to correct this problem.
Shunts are available from CERONIX. Shunt order number is CPM2011.
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