White nob either focus, H Stat ( convergence ) or G2. Look at the FBT
& see how many pots are on it. Usually 2 ( focus & G2 ). That will narrow
things down. It wont hurt to turn it & see.
If the other pot is the one almost under the anode connector it looks
like a high wattage pot maybe for hoz centering or width.
Cant help with color. It may need a Sony remote to get to it or the
right button push combo.
BTW does this take composite video ??
73 Zeno
LFOD !