Thursday, September 22, 2016

Interference (2), VDSL a HAM operators nightmare

Remember my post about interference last July? I did solve the problem for a while. But the modem/router did had a defect. We lost internet almost all evenings and I was not even transmitting! So, we got the newest modem a Experiabox V10. And back was the interference. Interference is worse when you receive it, but we have to live with it as this is going to be a big problem everywhere for radio enthousiasts. Even worse is the interference you cause when transmitting since we don't want to disturb people that have nothing to do with our hobby.

Orange light means no DSL signal
And so I went on with a lot of ferrite and tried everything I could. I solved the problem as far as only hick ups on TV and a internet connection that would get lost for a minute. Unfortenately still sometimes we lost the complete DSL connection and in that case we had to wait for 5 minutes to get TV, internet and phone back online. I was out of options and found a DSL RF protection filter at It did have a good review on several sites and this was my last hope for a solution. I tried to connect it last week but unfortenately the new Experiabox modem doesn't see any signal anymore with the filter connected. Tried to restart but still no signal till I disconnected the filter and plugged in the DSL wire directly in the modem. We had a internet connection again and I still had the problem.

Oh my, now we really had a problem. I'm not that clever with solutions curing RFI. This really needs a expert to solve the problem. So I checked some radioamateur forums and saw a post from another HAM that had the same problem with the same modem. And not only he had the problem, but some other HAMs as well. I got some feedback and found someone that could help as his interference problem, which was exactly the same, was solved completely. Not only at his modem but also at the modem of his neighbours. He found someone that could change the VDSL settings of the provider VDSL line, in their words: change my profile. It seems to be possible to place some HAM band notches on the signal, in other words the DSL signal is suppressed or is not using the frequencies we use as radioamateur. That would cost me some internetspeed but it would solve the problem. I contacted this person and he placed the notches. The interference disappeared magically and is completely over now. I can use 100W on all bands without disturbing TV, telephone or internet and the VDSL line is not disconnecting.

Problem solved you think? Oh yes, for now. But what if my provider changes the line profile again. And what about if I can't reach the guy that changes that profile for me? In the mean time I tried to find out why this remoterig RF-protection filter does not work the way they advertize? On the site I read the best way to ask something is via their forum. So I applied for a pasword but they need to approve. That was more then a week ago. I guess the guys in Sweden have a busy life.

Well I decided to register at the remoterig yahoo groups. The story is going to be too long for one post. So, more about it later...

Something to read about this.

It was all known 13 years ago already: DSL's dirty little secret revisited
PE4KH had a similair problem: Vectored VDSL and the influence of amateur radio transmissions
DH8BQA had a similair problem and basically did the same as me: Fixing issues: Remote Ops VDSL internet connection

I have the feeling I really got into something bad. I wonder when you are a new interested radioamateur and want to start on HF. You just got your license and then you bump into something complicated like this? I think I would give up and try another hobby....


  1. Hallo Bas, wat een gedoe allemaal. Gelukkig is het probleem dan opgelost. Ik heb ook een Experia Box v10. Geen enkel probleem hier. Dus even afkloppen. 73 Paul PC4T

    1. Hallo Paul, het ligt ook niet aan de modem denk ik. Het is de VDSL lijn die het internet brengt. Ik heb geen kabel maar een oude koperen telefoonlijn. Dat geeft natuurlijk problemen omdat die lijn uiteraard een prima antenne is voor de lage banden. Het probleem is eerst opgelost maar kan weer terugkomen. Ik zou graag een manier vinden om de storing zelf te verhelpen. Maar eenvoudig is dat waarschijnlijk niet. 73, Bas

    2. Ik snap het. Voorlopig ben je uit de brand, maar idd zou het fijn zijn omdat zelf te kunnen regelen. 73 Paul PC4T

  2. Hallo Bas, fijn dat voorlopig het probleem opgelost is.Gelukkigheb ik gekozen voor de kabel. Zowel telefoon, internet alsmede RTV. OOk die kon ik platleggen met 50W en meer. Gewoon een mantelstroomfilter/line-isolator in de kabel van de zender opgenomen en ben, ongeachte QRO vermogens van alle problemen af. En zelfs de ruis op mijn EndFed is minder geworden. 73 Hans, PE1BVQ

    1. Hallo Hans, inmiddels een line-isolator van je gekregen. Ik ga het uitproberen. 73, Bas


Thanks for your comment. Bedankt voor je reactie. 73, Bas