As I by example tried to point out in my previous post... different applications could very well require different grid choke designs...

in much of the discussion we've seen so far as re: grid chokes it has been seemingly assumed that all grid chokes are all built for a universal range of applications.

This is not the case... as the range or field of applications in vacuum tube audio can be so very wide... the best advice for any diy'er is to ask your magnetician... communicate with him\her and let them know what your doing. Then they can perhaps offer some constructive applications assistance.

but... don't confuse the notion... that all grid chokes are designed to work in all applications... or at least not optimally.

A grid choke for a source impedance of say 15K would be designed differently than a grid choke for a source impedance of 1.8K.

And any testing that fails to take this into account also fails.

msl