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The Panasonic speed-o-vision would use a series circuit for the tube filaments. I believe there is a resistor to drop the filament voltage in the standby mode, sometimes a diode is used to chop off either the negative or positive portions of the AC waveform...this is used without a filter capacitor in the instant on circuits to achieve an effective reduction in power to the filaments in standby mode. If the instant-on diode shorts, the filaments would be on all the time at full power.
I usually remove the instant on diode or re-wire the circuit so that the power switch shuts off all power. I don't mind waiting for the set to warm up and I believe this is safer.
Usually there is a pretty good amount of filament glow and also some appreciable heat from the tubes in the standby mode.
When you say the tubes glow red do you mean the plates? Filament glow=normal, red hot plates=overloaded tube. It is normal to get a lot of heat from tube sets, especially from the power output stages. A typical tube b/w portable is 110 watts...there is probably 50 watts or less of actual power being used to do work and there is 60 watts or more of heat to heat the tube filaments.
Picture roll after warm up is likely bad capacitors in vertical circuit. If there is both vertical roll and horizontal lines that you cannot syncronize with either the horiz. or vert. hold controls then the problem is in the sync separator circuit, again possibly bad caps.
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