Vertical Line - Raytheon Porthole 1602

[Electronic M]

Try pulling the audio detector tube (assuming it is a parallel heater set*) and see if the interference goes away. If it stays it is in the audio amp (or it's power supply), if it is gone check the RF/IF system....Though I'd fix the horizontal issue causing the line first....A lot of power goes through the H output tube and if it is set up real wrong (such as in your pic) it is possible for the tube to generate an RF pulse strong enough to be picked up by the tuner and interfere with the picture and or sound.