RCA XL100 portable with a dark screen

[zeno]

G-2 usually on the HV transformer or a seperate white block that
plugs into the CRT socket. Almost always its near the focus control.
Sometimes its called "SCREEN".
Be sure you have a good ground. Use either the CRT shielding
or the shielding around the IF stages. There also should be a
layout chart in the back to help you.

73 Zeno
LFOD !