WebSDR is a great tool for people to use, for all sorts of reasons. Personally, I use it to listen to military communications, however you can use it for whatever you feel fits you!
Understanding the site, Pt. 1
The first thing you’re going to want to do is head here. Once you’re on the Utwente WebSDR, you’re going to be presented with a screen that might look quite confusing at first, but do not worry, it is quite simple to use! Ignore everything that is above the waterfall (the waterfall is the blue/black screen that shows activity on a frequency). If you’d like to use a name for the chat on the website, input your name in the text box above the waterfall, if not, ignore everything that is above it like I mentioned.
Now, below the waterfall you’ll see multiple options, multiple things to select and adjust, but we’re going to start from the left and work our way to the right. On the left, below the waterfall, you’ll see a box to enter numbers. In here is where you’ll input the frequency you’d like to listen to. I use WebSDR to listen to military comms, so I’d enter one of the military frequencies in this box here. If you know a channel you’d like to tune to, input that channel here. Below that you’ll see CW, LSB, USB, AM, FM and AMsync. When I listen to mil comms, I use USB. But, depending on what you’re listening to, you might need to adjust this. If you’re having a tough time hearing something on a specific channel, try adjusting your selection here until you can hear it.
Below this you’ll see a volume slider, and a mute button, fairly self explanitory. In the box on the right, you’ll see at the top a filter. The filter depends entirely on how audible what you’re listening to is. If I’m listening to military communications, and I can’t quite hear what I’m listening to, sometimes I’ll adjust the filter wider until the communications become more audible. Most of the time I try and keep my filter at around 3.37 kHz to 3.75 kHz. Below the filter you’ll see an option for squelch, autonotch and noise reduction. Personally, I only use Squelch. Squelch filters out all of the background static that you’d typically hear on a radio. If you’re some kind of crazy person and can handle that static noise all the time, feel free to leave squelch unchecked. In regards to the other two, I don’t use them.
Below this you’ll see an audio recording selection. If you click start, it’ll begin to record everything you’re currently listening to. When you’re done recording, click “stop” and then save and your audio recording will begin downloading. If I upload the audio recording typically I use a website call Vocaroo, which can be found here. Next to that box, you’ll see an audio meter area, which simply shows the levels of audio coming through at that time. Then finally you’ll see your waterfall zoom, which is simply a control for the waterfall which is seen above.
If you’d like, you can use your mouse to drag across the waterfall, using your scroll wheel to zoom in and out, to discover some other stations. If you get into the lower numbers, you can find some neat stuff! I’ve listened to BBC Radio before simply from using Utwente WebSDR.
Understanding the site, Pt. 2
Once you’ve gotten a good understanding of the top portion of options, we’ll move onto the second list of options right below them. Starting with “Waterfall settings”. In here, you’ll see options to zoom out, zoom in, max out, band and max in. Typically I don’t use these buttons, as I use my mouse for all controls on the waterfall. I keep my speed at slow, the size at medium (sometimes large), the view is kept at waterfall, brightness is kept default, and I don’t select anything on the last window.
Moving onto “Memories”. I rarely use this, so I’m not 100% sure what everything here does, best to just leave this one go. The users tab simply shows how many users are currently on the site. Chatbox is self explanitory, it’s a chatbox. If you type in the chatbox and have a username, you’ll see your message pop up in the chatbox. Please, be respectful to the people on the site! Logbook is useful if you’d like to log something you’ve heard, however, people don’t always use this so sometimes it’s difficult to catch certain things. But, if you’d like to help out the site and the people using it, log something you find interesting!
Station info is a tab where you’ll be able to scan websites for information on the station you’re currently tuned into. Simply click one of the sites, and then either wait for the site to pop up on Utwente, or click the hyper link right below the database selection area. S-meter plot simply shows activity on the frequency at a given time. In advanced I leave everything the way that it is, I don’t adjust anything here.
What frequencies should I listen to?
If this is a question you have, then you need to ask yourself “What do I want to listen to?”. If you’re going to primarily use the website to listen to military communications, your primary frequencies are going to be as follows.
4724, 6739, 8992, 11175, 13200, 15016 and 6712 (RAF Croughton).
If one of these doesn’t work, try another, until you’re able to find a station that comes in clear. It all depends on the time of the day, and the weather. There’s also loads of reported discrete frequencies as well, which can be found here. I cannot verify that those discrete frequencies actually are still used though.. just gotta mess around with ‘em and see if they work. That link is also great at explaining what exactly these communications are. Here’s what exactly HFGCS is capable of providing.
- General Phone Patch and Message Relay Services
- Automatic Line Establishment
- HF Data Support
- Command and Control Mission Following
- Emergency Assistance
- Broadcasts (EAMs and “Skyking” messages)
- HD Direction Finding Assistance
- ATC Support
- E-Mail connectivity to NIPRNeT and SIPRNeT
As you can see, HFGCS is used for a wide variety of things. Just because you hear an Emergency Action Message (EAM) or a “Skyking” broadcast, doesn’t mean the United States is about to nuke a country. Also, do not attempt to understand what these messsages mean. Not only is it a giant waste of time, as the only person that knows what an EAM message means is the person receiving it, but it’d also land you in a hell of a lot of trouble. Just don’t do it.If you’ve got any questions at all regarding HFGCS and WebSDR, do not hesitate to reach out to me on Twitter via DMs, or Discord (Doge #1337) and I’ll gladly help you out!