Jburidan - Per Jim McShane (one of two local tube sellers) the type 3 is a wonderful tube as long as you didn't get the last from the factory. The last ones had mis-aligned heaters which caused the anodes to get cherry red (typically in a few hrs) before arcing over resulting in premature failures. Probably not many left. I have 2 quads of type3 and 3 quads of type2. Except for the type3's being slightly lighter (thinner glass) and the lack of spot welds on the anodes they sound the same to me.
So I do agree there may be a handful of bad type3's still out there there are a lot more good ones left. The type1's were the worst by far.
So I do agree there may be a handful of bad type3's still out there there are a lot more good ones left. The type1's were the worst by far.