Hi there! Today I'm going to be talking about the wonderful world of shortwave radio monitoring!
First off, what is shortwave? Shortwave is part of the radio part of the electromagnetic spectrum, it is between 3MHz and 30MHz. It is usually referred to as the dark web of radio. This is due to the very many "weird" transmissions taking place, either 24/7 or intermittently. One of the most famous examples of a "creepy" shortwave transmission is of "The Buzzer". It buzzes away, 24/7, only stopping when the operators (the Russian Western Military District) need to transmit a voice sample. Here's a sample.
But that's far from all that you'll see on the bands. Number stations are another prime example. Huh? What's a number station? Number stations are shortwave transmissions from foreign intelligence agencies to spies in the field of foreign countries. They carry encrypted messages in form of groups of numbers, using either automated voice, Morse code, or a digital mode. The encryption methods used by most number stations is widely believed to be the one-time pad (Explanation from Priyom). A very popular one is the Polish operated station "Oblique" formally known as E11, it gets its name from the usage of the word "Oblique" in messages. E11 is a remnant from the cold war, and is still active to this day. It sends messages on every schedule once every month. But that doesn't mean that it doesn't transmit when it schedule indicates a transmission, it will transmit, just a null message, a message without the message. If you want more detail about this station you should check out the page on Priyom about it: Here it is!
So how do you listen to shortwave? Well, the chance is very high you might not have a shortwave radio, so what are your options? Well, there are quite a few, my personal favorite is the RTL-SDR (I use their v3 variant), it's cheap, easy to get and comes with (albeit not very good) HF (Shortwave) support out of the box. You will however need a new antenna, as the included one (if you buy the bundle that is) isn't meant to recieve shortwave at all. I got a magnetic loop antenna, which works wonders for me, they're also easy to get as everyone and their dog makes one so getting one isn't an issue at all. While they aren't the peak of antennas, even at their price point, they're very easy to set up. Another antenna is the mini-whip, which requires a bit more knowledge in things like soldering, but will elevate your listening experience even further for the same, or even less money. Another good thing to buy for things like an RTL-SDR is an upconverter. Since the RTL-SDR has no native HF support, we can emulate it by shifting the shortwave bands to the bands the RTL-SDR does support natively. A good example is the Nooelec Ham-It-Up. But what about a different reciever? You can obviously go with a desktop reciever like the ICOM IC-R8600, but if you want one that can plug into your PC the SDRplay is a good bet, it has native (and good) shortwave support built in, but does cost more, and you're not out of the woods yet, as you will need an antenna that can pick up shortwave.
But what if you don't want to spend any money? Well, have I got the treat for you! There's a free shortwave radio on the internet (Multiple even)! It is completely free of charge and has all the prerequisites for a good listening experience. Just head on over to http://websdr.ewi.utwente.nl:8901 and start listening away! It's shortwave with less of the disadvantages. If you want to know when number stations will transmit and where, you can do that over at https://priyom.org.
But that wraps up my post. Next time I'm talking about this I want to go way more in depth in the spying cases surrounding number stations, and how they work in general.
Thank you for reading this, and have a great day/night!