what is a short wave radio and how do you get one
Please read at the link to save space here. Short wave was the original radio invented by Marconi, Tesla and I suppose others. It was used internationally because of what is called 'skip' - the broadcast signal could hit the ionoshpere and bounce back to the ground, then bounce back to the ionosphere and so forth.
Calling a 100 meter length signal today 'short wave' is laughable. Microwave signals and cell phones use a tiny fraction of a meter in length. But short wave can skip while the higher frequencies are 'line of sight'.
About SKIP: obviously the more power you use to drive the signal the more distance you can achieve. Short wave uses almost solely AM (amplitude modulation) and at night just the ground wave (before skip) can be extensive with enough power. Some of our oldest radio stations on AM are powerful, at night, with 50,000 watts (amplitude) of power.
Short wave radio receivers today are almost all digital, which makes finding the frequency you want much easier. A good receiver needs a long antenna; most digital receivers accomplish this - to some extent - with a small 'loop antenna' internally. However, the longer antenna that you can put up - at the desired frequency length - the better the reception.
This is more than I intended to post. If you have no knowledge of the medium you should study it, starting with the Wiki article. :^)