8 inch RCA

[jr_tech]

Possibly by removing the antenna, one can reach in with needle nose pliers and grasp the cardboard tube that surrounds the neck of the CRT well enough to turn it to adjust the trap. Otherwise remove the chassis from the can.

jr

[timmy]

The cardboard is used to move the magnet ?

[jr_tech]

Yes...Phil N says it far better than I can.

"On this set, the ion trap is adjusted by manipulating a little metal collar around the neck of the picture tube. A stiff paper sleeve is provided to let you do this without poking instruments down into the narrow space between the picture tube neck and its surrounding metal shield. The paper immediately broke when I tried to move it, however, so I ended up poking a long crooked-neck tweezers in far enough to reach the metal collar.

Sure enough, when I pushed the collar in, the picture immediately grew brighter. Working a bit at a time, I adjusted the trap so that the picture had normal brightness."

From https://antiqueradio.org/rca16.htm

jr