I have a radio interference problem in a house. The problem appears only on the FM channels and there are two similar radios with the same problem. They are in different parts of the house and on different circuits. The problem is with fluorescent lights, only.
In the attached garage there are 6 x 4 foot, 4 lamp T8 fixtures. They have Sylvania Osram ballasts. They are on two switches and it doesn't matter which switch is on.
In the kitchen, there are 2 x 4 foot, 1 lamp T8 fixtures on one switch.
The house is about 3 years old and the problem has been there for the whole time, winter and summer.
The grounding is a ground plate and the system is properly bonded. All line, neutral and ground connections are tight.
I tried a .1 mfd capacitor in a garage fixture and in the panel, in all possible configurations (L-N, N-G, L-G, L1-L2) with no improvement.
With the radio outside and plugged it into an outside plug, the problem was still there, but the FM signal was weak. It is probably weak in the house, too, but it's bad outside.
I plugged the radio into a 100 foot cord and there might have been some improvement. Then, I plugged the 100 foot cord into the neighbor's house and the problem was gone. Both houses are fed from the same pole.
The neighbor has fluorescent fixtures that don't interfere with my customer's radio - a different make of ballast, though.
My conclusion is that the problem is in the wires, but now I'm out of ideas. The house is an hour away, so I can't go back unless I have a solution.
What did I miss?
Is there a filter I install on the panel?
Is there a filter I can plug the radios into?
