On my St-70 V2 tube plate seems to glow on one corner of vertical plate. After shut off the "burn" then looks like a water stain...if I am describing it right. i.e a small stain on the corner of the plate.
Kinda weird. My resistor is reading very much in range of 15.6 -15.8 ohms. The other is reading well within 1000 ohm range.
any thoughts
thnx