[Amps] 4-250a mounting

[Peter Chadwick]

As I understand it, the filament structure is the same as the 3-500Z. Not sure about filament to grid spacing, but I have had some go grid to filament short when hot, and that's with them mounted vertically. Depending how many tubes you have, it could be worth trying. Rich Measures may have some historical knowledge of 3-500 failure modes which could be applicable. I think personally, I'd avoid it, but that's partially because I don't have a lot of spares!

73
Peter G3RZP