[Heathkit] 6293 tube question

[Ken Kaplan]

I just got an RCA 6293 (lot 60-22) yesterday. I thought that they were visibly more robust than 
a 6146. I held it next to an RCA 6146 (lot 58-48) and compared what I could see of the 
internals and they look the same to me. The plate material is the same thickness as are all of 
the other visible internal pieces. Am I mistaken about visible internal differences or - drum roll 
- have I been scammed? The marking on the tube looks original (just like those $50's I have 
stacked in a shoe box - just kidding). Is there a way to visually verify its a 6293 and not a 
6146? No, I'm not getting out my glass cutter. Heath content? It's for my SB-110A.

73 Ken kb7rgg