You might try moving the tubes from one channel to another. Just because a tube lights, does not mean that it's working.
Usually, the cathode resistors do the duty of fuses, they are designed to fry instead of the output trannies or tubes. You can usually tell visually if this has happened, but if you don't know what you are doing, don't be messing around with the bottom off, there are lethal voltages in there. Death would really ruin your Christmas, take it to a repair shop if in doubt.
Usually, the cathode resistors do the duty of fuses, they are designed to fry instead of the output trannies or tubes. You can usually tell visually if this has happened, but if you don't know what you are doing, don't be messing around with the bottom off, there are lethal voltages in there. Death would really ruin your Christmas, take it to a repair shop if in doubt.