Question for the monitor experts

Ace20

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How important is low resistance on tube ground (aquadag) to the neckboard / frame? I am trying to track down a video noise issue on a Sanyo 20ez and noticed the ground strapping wires on the tube are a little corroded and it's done some damage to the aquadag on the tube. Using a meter it's still making a connection but it looks to have about 2k ohms of resistance depending on where I measure. I haven't got easy access to another tube to compare but is it usually a perfect near 0 ohms connection?

I've been down the rabbit hole with this one as I've already recapped the chassis, tried another power supply, another game board, all new pots on chassis and game board then going from Bob Roberts weave (I think he means wave) page replaced the LA5112 and 2SD1090 with new ones from arcadepartsandrepair and no change.
 
The Aquadag on a tube essentially turns the tube itself into a huge filter capacitor. It is critical in most deflection circuits for correct operation. Congruent with your symptoms, a tube will generally still operate without the Aquadag-ground strap combo, but you will get weird issues due to lack of filtering. I would definitely clean it up not only where it contacts the tube, but where the ground straps contact the frame. Best of luck, these kind of problem will drive you mad!
 
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