Total posts : 45366
Most of the MW (Medium Wave) loops we see are usually fairly large, but I have a component AM tuner that has a small MW rectangular loop contained within 1/4″ plastic piping, dimensions 6″ X 2.5″. It is mounted to a swivel on the rear of the tuner so that the loop can stand out at right-angles to the back of the tuner, or swung flat against the back of the tuner. It also can be lifted off and has a 2′ wire so that it can be placed away from the tuner a little bit. It works amazingly well for reception.
I am thinking the same question about whether the shape of a loop makes any difference is possibly comparable to a question I had as to whether the shape of a loading coil made any difference, and somebody told me it did not matter. So I made the loading coil for my AMT3000 triangular, and it loads up wonderfully.