I have an AM radio on an aluminum boat. The radio is shielded on
six sides by aluminum. I want to mount an antenna on the boat and
run coax inside and couple the signal to the ferrite rod in the radio.
I'm thinking about an active whip antenna with a 50 ohm output. If I
did this, I would have a coax with 50 source impedance at the radio!
How do I create a 50 ohm load at the radio over the AM band? The radio
has a 2-3/8" x 3/8" ferrite rod.

I would appreciate any other solutions to get a signal to my radio.

Mike