Ok... 1. I do not own a soldering iron and have no clue how to solder anything. I can spell solder though! 2. My HOA would have a roaring fit if I started string 200 plus feet of wire in the trees! 3. My stereo does not have "jacks". Just little "holes" that you insert twisted wire into and then close the latches. and 4. It is most definitely the AM antenna wire loop. Says so on the loop, the stereo antenna "holes" etc. There's also a place for an FM loop should I ever find one of those. 5. It's in my house near a window and yes I've tried facing that loop all over the place. It's about 6ft fully unwound.
Perhaps I should see if I can find any tv antenna somewhere. That seems workable if I can just twist wires. By the way.. we have a newer (6-7 yr old) boom box (small, not the big one) that has a silver directional antenna. It also has a hard time getting certain AM stations. Oddly enough... our REALLY old (30 year old) alarm clock radio gets AM stations perfectly! Go figure.
I was hoping to find some store that has people who are old enough to know about old tech.