For the aspiring radio hams is the medium wave band particularly interesting because in this frequency range to build the circuits are still quite easily and show no unconventional HF behavior.
The number of available stations is quite high, so that can achieve success very quickly.
There are different circuit designs, with both tubes, transistors and integrated circuits / ZN414.
Here is a selection of interesting links to medium wave receiver

Here you may find Circuit, Basics, Schematic Diagram and DIY Kit components for AM receiver (medium wave)