Ah, another forehead-slap moment. Lower resistance means lower wattage, duh.
I reviewed the photos that I took while experimenting, and it's clear that increasing the resistance stretches the left half of the image, while decreasing resistance squeezes the left half.
Changing the resistance also changes the overall width somewhat. And it does not really cure the non-linearity I'm seeing. The far left edge is still squeezed, etc. And there is an additional variable -- the value of the .22 cap added to increase the overall width.
Finding the best setting looks like a very iterative process:
-- Try new resistor value
-- Adjust the width, horizontal linearity, and horizontal drive controls for best linearity
-- Try another resistor value
-- Adjust all the etc.
-- Repeat, repeat (maybe also adjusting the value of the .22 width-coil cap to see how that effects everything)
That would be simpler with a direct-view TV, which you could plop onto the workbench and easily view while adjusting. Not so much fun when you are crouching on the floor to make adjustments and peering around to view the results in a little serviceman's mirror on the other side of the cabinet.
OK, enough whining already! I hope to make some progress this weekend.
Phil Nelson
Quote:
Originally Posted by old_coot88
Phil, it might be worth trying the old "seven seconds off & back on" test. Does the raster come back at full width, or is it slow filling out? If unusually slow, are there any peculiarities with the lin during fill-out?
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P.S. I did try the seven-second test suggested by old_coot88. The raster comes back at full width. You can hear that the HV spools up slightly after everything else, so there's a brief interval with no raster. But when it reappears, the image is at its full width.