Determine the received strength of a transmitted signal
To gauge shortwave pirate radio activity in 2018, I analyzed the Shortwave Pirate loggings forum of the HF Underground (http://www.hfunderground.com). A computer script parsed the message thread titles, as well as the timestamps of the messages. This information was used to produce some statistics about the level of pirate radio activity. Of course, as Mark Twain has written: “There are three kinds of lies: lies, damned lies, and statistics.” A fourth might be pirate logging message titles. Don’t expect all the numbers to exactly add up. Still, let’s see what we can learn.
There were 12,785 messages posted to 2,216 unique threads. Activity levels are essentially flat, down slightly from 2017, but still at historically high levels. Back in the 1990s, it was not uncommon for an entire month to go by with only a handful of pirate stations logged. If you want to know when the “golden age” of shortwave pirate radio was, I would say it is right now.
Ideally, each thread represents an individual pirate station transmission. Also ideally, each message posted to a thread represents one logging. In reality, there is some error involved. Let’s dive in.
First, we can look at the transmission mode used:
AM leads USB, with the other modes much less often used.
Next, we can see how much activity there is for each day of the week:
As expected, weekends are by far the most active, but there’s still pirates to be found during the weekdays.
We can also look at the number of logging threads per month, to gauge activity:
There was a bit of a late summer / fall slump, but a very active holiday season.
We might be interested in knowing the best time of the day to try to hear a pirate station. Here’s a plot of the start times of the logged broadcasts, binned
by UTC hour of the day:
Most activity is in the evening as expected. But there’s still a fair amount of morning/afternoon activity. Not much in the wee overnight hours.
Here’s a graph showing the number of broadcasts per day of the year that were logged:
Finally some graphs of logging threads per frequency:
And zoomed in vertically to see the less commonly used frequencies:
6925 is the place to be, and most activity is on 43 meters, but there’s still a fair bit elsewhere. Old Time Radio on 6770 AM really sticks out.
If you’re interested in hearing pirates, the best ways to keep up to date on what is being heard is via the HFUnderground.com message board, as well as the real time Rocket Chat. Rather than finding out about a transmission after it is over, you can tune in while it is still on the air. Also visit our Facebook group.
And of course, your loggings and other posts on the HF Underground are most welcome! This is how we find out what stations are being heard.