RF problem with VFD help

Hello list.
I have an inverter 220 single phase 40 amps draw at full load, it
generates alot of RF noise on the AM radios.

To eliminate this noise problem seems to be more of a challange then I
had hoped for but I have to eliminate this. I have installed a 1" pipe
in the ground about four feet down and then removed a screw from the
condute inspection cover from the hydro meter and ran a wire from the
meter cover down to this grounding rod. This helps some. I also grounded
the machine to the breaker box since it is about 20 feet from the box I
took the liberty of using alot heavier wire then is required. I also
installed the inverter in a steel NEMA box. I have two options that I
know of left. Build a filter or use an isolation transformer.

The transformer is expensive so I looked through some electronics books
and found a low pass filter which is suposed to pass 60 HZ



220 single phase in __________L1_____I___________ SINGLE PHASE OUT
I
I
C1
I
I
220 single phase in __________L2______I____________SINGLE PHASE OUT

C1=0.01 UF
L1 & L2 1MH

The capacitor is no problem but where can I get a coil that will pass
the 40 amps?
Is there a better way to eliminate this RF?

Thanks
Stan