Triac stopped Internet
LA6WNA
Posts: 138
Hi. Last week I discovered a for me new experience. RF noise from a 230v AC triac regulator caused my ADSL line to slow down, and at last compleetly stop.
Earlier I`ve called the Internet prowider because of slow connection, and they measured the line and told me that there was some kind of noise at the line. They could not tell me what kind of noise, or where it came from. Only that this could cause slow connection. Last week the router stopped compleetly and just resets end resets all the time. Then I decided to do some more investigation.
Before I found the source to the trouble, I`ve disconnected almost everything in my house, Problem still there. Then I connected the scope to the mains supply, and there I could see a spike in every sine cycle. Just like the phase cutting triac regulation. Then I remembered a 1700W regulator in the house.,, Jepp, thats where the problem where.
When I disconnected this one, Internet came back.
So, end of story; I made a RC snubber circuit over the triac and added a ferrite inductor between the triac and the load and now I got my 5mbit Internet connection back again.
Any others out there that had similar problems?
Earlier I`ve called the Internet prowider because of slow connection, and they measured the line and told me that there was some kind of noise at the line. They could not tell me what kind of noise, or where it came from. Only that this could cause slow connection. Last week the router stopped compleetly and just resets end resets all the time. Then I decided to do some more investigation.
Before I found the source to the trouble, I`ve disconnected almost everything in my house, Problem still there. Then I connected the scope to the mains supply, and there I could see a spike in every sine cycle. Just like the phase cutting triac regulation. Then I remembered a 1700W regulator in the house.,, Jepp, thats where the problem where.
When I disconnected this one, Internet came back.
So, end of story; I made a RC snubber circuit over the triac and added a ferrite inductor between the triac and the load and now I got my 5mbit Internet connection back again.
Any others out there that had similar problems?
Comments
Congrats on finding that.
Once we had an FM broadcast radio in a lab that would sometimes not work. The station we were listening to would just disappear. And most of the others as well. We always meant to open it up and see what was wrong. Before we did someone noticed that whenever a particular piece of equipment was turned on the radio would go dead.
Turned out that that equipment had a 7805 voltage regulator in a big TO-3 package that was oscillating and blasting out RF all over the FM band.
Never thought a 7805 would have the bandwidth! high inductance ground connection I assume. There'll be radio hams trying to QRP with
one now!
I use two main methods to find such noise; HF-radio where I can hear the noise and ocilloscope where I can see it.
That 7805 regulator ocillating was new to me, but it surely could happen. Guess it where in combination with cap`s and inductors in the circuit, and then the most unexpected things could happens. With so many radiovawes in the air, one thing is for sure; one day some of them will interfere with eachother. We`ll have to live with it.