Having also been brought up on valves (and don't remember that type either !), I'm puzzled by Nos 9 and 13 taking top left as 1, They appear to be the same with the grid leads reversed, but what is the thing connected to the cathode ?
Rob
Have you skipped a row?
Assuming you're still refering to
Possibly you're referring to Nos. 14 and 19?
The valve is a beam tetrode, such as a 6V6, and the 'thing' is the beam plates.
You are right about the transposed grid connections. All the other valves have double- sided grid connections (actually, one grid connection is missing) so that the user can delete the unwanted ones. Presumably the original designer felt the need to have two diagrams because of possible confusion with the internal connection up the right hand side.
,
I've drawn the double diode triode and the beam tetrode symbols much as I remember them.
Perhaps these will be more easily recognisable? I hope so!
RS offer a free one called DesignSpark
Painters10
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