[ValveTones]

Thanks Bob, yeah the 3422 looks like a great choke, nicely spec'ed for many audio projects. Philco apparently used Jefferson for their transformers in the early days, and i must say, i haven't seen a nicer looking piece of iron. They seem to be extremely well constructed.  

The 3422 i can easily find a job for, its that other mut, the 3518 that i am wondering about.
With values like it has ( 150hy @ 10 mA and 4k dcr ) it would seem easy to assume it must be some space station part that i would never find a use for. 

However, being as though it is so nicely constructed, i would hate to get rid of it without knowing its purpose.
Maybe philco engineers did something really clever with this part, my aim is to find out if i'll be missing out on any glorious audio achievements by assuming (do to the specs) that this part is totally useless.

I've had to kick myself before getting rid of unknowns like this. Trying to exercise a different mindset you know.

BTW- i checked out that model 15 schem, and see that the 3422 was used in a capacitor input filter set up. 

I've been trying to figure out how to properly apply the choke input filter setup as i have several builds under class A consideration.   But need to figure out how to do this with a fixed value choke rather than a swinging choke.

Anyhow, Thank you Bob for your reply.