12at7 or 12au7

[dieseljeep]

Originally Posted by timmy

They are for the pilot tv so I was wondering why it don't have all that good of sound and picture, I have 12au7 in there so I'm sure it will improve with the right ones, it was designed for the at7 s.

I had to look at the schematic, the set uses three 12AT7's. The 12AU7, never did make a good tuner tube. Even if you have a 12AT7, that's a little weak, it's still better than using a 12AU7.
Once in a while, the tube sub guides, can lead you down the wrong path.