HF LPF at antenna balun
 

I would like to add a simple lowpass filter to a T2FD antenna I have. My
QTH is about a mile from several FM and TV xmitters and I'd like to scrub
them off before they even hit the 9:1 balun while in the 490ohm balanced
domain using a simple filter. ( like two coils and two caps )

Anybody have a link to make the calculations of the components?

Is there a better way?