Picture Tube Brightener

[old_tv_nut]

These do not increase brightness of a good tube. They contain a transformer that raises the filament voltage. That increases the cathode temperature, temporarily increasing the electron emission of a worn tube with weak emission. They also make the cathodes wear out faster, so they are definitely a temporary fix for an old tube that is near the end of its life.

[TVTim]

Originally Posted by old_tv_nut

These do not increase brightness of a good tube. They contain a transformer that raises the filament voltage. That increases the cathode temperature, temporarily increasing the electron emission of a worn tube with weak emission. They also make the cathodes wear out faster, so they are definitely a temporary fix for an old tube that is near the end of its life.

Ah! Now I know. Thank you!