In many areas of the UK, all of the HF amateur bands up to and including 20m are being blighted by interference from VDSL (Very high-speed Digital Subscriber Line)
This is the most widespread means of providing residential broadband internet services in the UK. Ofcom, which is responsible for investigating radio interference, says that it receives, on average, only six complaints per year on the topic and won’t take any significant action.
The RSGB President wrote a letter (1-page/385KB PDF) in the May edition of RadCom asking every radio amateur who suffers from VDSL interference to submit a complaint to Ofcom so that we can demonstrate the size of the problem.
How you can help
- Identify and measure the VDSL interference you are experiencing. You can read the guidance outlined (1-page/371KB PDF) in the RadCom article, or use the Lelantos software provided below
- Submit your complaint to Ofcom. It is better if each radio amateur uses their own words, highlighting their experiences and the effect of interference on them. However, we have provided a pro forma letter to help (2-page/24KB Microsoft Word document)
- Copy your submission to your local MP to raise the profile of the complaints. You are welcome to include a copy of the RadCom article (3-page/1.2MB PDF) as background
- Email a copy of your submission to us via firstname.lastname@example.org so that we can track the number of complaints and pursue them with Ofcom
Need some help?
You can email email@example.com and members of the EMC Committee will guide you through the process.
Note that the example .WAV files linked from this page are short, wide bandwidth (2Msps) spectrum recordings and not suitable for playback on normal media players – the files are intended as samples for Lelantos.
The presence of VDSL interference can be proven using a software tool called Lelantos developed by Dr Martin Sach, G8KDF—a member of the RSGB EMCC. It is a stand-alone Microsoft Windows application. If you have an SDR receiver and a PC running Microsoft Windows, you can download Lelantos below. Further details of how Lelantos works can be found in the instruction manual below and in the article referenced above from the November 2018 RadCom.
Download Lelantos software, sample test files and manual
The Lelantos software has been provided by the RSGB “as is” and the Society cannot be held responsible for issues caused by the software on your system. By following the links below you agree to download and install Lelantos at your own risk.
Right-click an item to download it to your computer—
- Lelantos manual (8-page/805KB PDF)
- Lelantos setup (5.54MB Microsoft Windows executable file)
- Example 6 to 14MHz RFIQ file (3.81MB WAV file)
- Example 11 to 13MHz RFIQ file (11.4MB WAV file)
- RadCom November 2018 article (5-page/3.1MB PDF)
- EMC Leaflet 15 on VDSL
- Lelantos119 Features Manual