Did you end up trying the resistor swap? IIRC it was originally recommended by grantspain to give the chassis a heater resistor that more closely matches that found on a MS9.
I did not. I'll probably try it.
The problem is that a smaller ohm resistor will put more voltage to the heater which could reduce the life of the tube if it's more than 6.3V what these tubes are specced for. Yes, you get a brighter picture, but you're also shortening the life of the tube.
Without accurately measuring the voltage it's all guess work. I don't own a RMS meter so I don't know if that gives at least a ballpark figure. The schematic in the elektrotanya link is for a meter than converts the heater voltage into light and then measures the intensity. It's pretty novel.
I think increasing the heater voltage will exponentially reduce tube life. It’s a good thing to do if you have literally no other options.
If the voltage is less than 6.3V, that's not good for the tube either. Like I said, without accurately measuring the voltage, it's guesswork.
2930 / 31 seem to reach lower emissions faster than many other monitors, so I wouldn't be surprised if the voltage is more than 6.3V with these chassis.
I did the resistor swap. It's definitely brighter.
I'll leave the resistor in.
My Cabs: Blast City | Blast City | Egret 2| Egret 3| Windy II | Neogeo 6Slot | Centipede Cab/cocktail| TMNT | DkJR
It's just a regular 2.2 ohm 1W flameproof resistor. I picked it up from a local electronics store.