Cannot get perfect focus - multiple colors and multiple lines
The perfect focus starts but stops at 22% when it goes from one color to the next. when watching a football game there are 2 lilnes, one green one red.
Televison & Video - Akai - PT4298HD Rear Projection Television
Answers & Comments
The problem is that the convergence board needs to be rebuilt. The board is located up and to the left looking in the back of the unit. It has two large Sanyo stk392-040 amps mounted to it and a grouping of 3.9 ohm 1/2w fp resistors in the yoke return circuit out in front of the amps. It's likely one or more of these will also need to be replaced.
If you're going to attempt this yourself you need to be VERY good at soldering and desoldering and toy should have a good VU meter to check the resistance and tolerance of the components out in front of those amps... Also think about adding a fan to the face of that board with a 9v regulator operating off the 20v +/- line feed. This will substantially keep the amps cooler and less likely to short out again.
If you would like to justa have this done our shop rebuilds these units for $225.00 dollars which includes shipping back to you...
Hope this helps!
Bill
William Rayburn, CET
Premium Technologies
PO Box 442
Long Beach, WA. 98631
360-642-4993