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I agree with oldtvman don't overlook the basics. Controls switches and tube sockets must be clean. Check for bad solder connections at the tube sockets, and the circuit board ground points. Try to do a gray scale setup. Turning up the strong gun probably will not tell you much. If you can not get proper gray scale, the crt may be to week. I don't think the horiz centering is the problem with the width. Width is effected by the horizontal efficency adjustment. In other words you may have given yourself a couple of clues. If the flyback is running hot, you are drawing to much current in the horiz output. This will cause insufficent width. You will verify this when you check the je6 cathode current. This could also cause low high voltage (dim picture, bad focus etc). You need to get that test equipment up to par. You will definately need to measure over 200 volts when working with tubes. Also be sure to check all the power supply voltages. 405 volt source could be low. Does the brightness control work? What about the service switch? I would expect a negative voltage on pin 2 of the 12by7. This comes from the grid of the blanker tube, a 6gu7 whose other half is the g-y amp in the demodulator circuit, through a 680k resistor.
Bill R.
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