? I picked up a dozen 3 bulb fixtures at the local habitat and installed them in my shop . Since the fixtures had no tubes I installed Sylvania Substitube LEDs . The lights work great , instant on and plenty of light . Only problem is , I have zero radio reception with the lights on . I have put ferrite filters on everything to no avail . My question is , can I eliminate the ballasts , possibly replacing them with LED Drivers ? Would that cure my woes? shop radio is a must have and I don't want to go incandescent.

  • It depends on the model of led tubes you purchased , some can use the ballast and are bypass compatabIe. I would check to see, I purchase ballast bypass lamps but the last batch could go with or without, no noise without, have not tried with.
    – Ed Beal
    Jan 17 '18 at 23:17

You bought LED replacement "tubes" which are called plug-n-play and allow you to not mess with the ballast -- but also require you retain the ballast. You are now married to the worst of both worlds: the EMI/RFI output of the legacy ballast, which could be considerable for a magnetic ballast, and also whatever EMI is coming from the new LED "tubes", which can also be considerable if they're cheap.

If you really want to go LED, you would be better off going with LED direct-wire replacement "tubes", and bypassing the ballast. You may want to consult the Sylvania documentation and see if they are capable of also operating in direct-wire mode; some are dual-mode like that. Don't just give it a whirl.

Otherwise pull down your fixtures, see how they are wired (instant vs rapid start, 1 vs 2 wires per lamp end) and get direct-wire LED "tubes" which are compatible with your lamp wiring. And bypass the ballast. Be sure to consult the factory to learn what kind of EMI the LED "tubes" will be emitting if any.

Plan "B" is to find a quality ballast with known very low EMI, and change that ballast, then either try your LED "tubes" or just use real fluorescent tubes. The light from them is superb these days, better than LED.

Plan "C" is that they make DC power supplies with the same formfactor as fluorescent ballasts. I scored several hundred of them on eBay for nothin'. Then get LED strips, two 5m rolls of 3528s should replace 3 fluorescent tubes, and cut them to fit in the fixture and power them off that DC supply. Obviously, the EMI output of the power supply will be the ruling factor; DC LED strips have no EMI at all unless you dim them.

Lastly, check your grounding. If your grounding is less than tip-top, it will greatly increase EMI. If the grounding is not tip-top, make it so, remembering that Code now broadly allows retrofitting of just a ground wire.

  • Some are both ballast bypass and will work with some ballast , without the model we don't know. If these were commercial ballast they have a higher RFI or noise ratio than residential rated ballast.
    – Ed Beal
    Jan 18 '18 at 1:39
  • The source of the RF causing this much of terrible EMI cannot be the ballast but the LED tube itself. One end of the tube have a switching current regulator and the long strip of LED in the tube is acting as antenna. Any emi filter out side of the tube won't help at all. Nothing you can do expect buying a FCC certified better quality tube. Jan 18 '18 at 2:40
  • @soosaisteven that wouldn't surprise me generally, but Sylvania should be better stuff than that. Of course any such LED "tube" has an uphill battle since it doesn't have a ground, and doesn't even know which terminal will be hot and which neutral. I don't have those kinds of "kill my radio" problems with real fluorescent tubes, even though there is Hf on those. Jan 18 '18 at 4:25
  • @Harper you are right on - the worst of both worlds. And even 'name brand' LED's can be just as bad RF wise as the El Cheapo's..
    – Ken
    Jan 18 '18 at 5:27
  • The term, ballast being increasingly misused. Lately I have seen few LED products designed to operate on mains voltage. The advert bluntly saying ballast is built-in, another was saying no ballast is required. I'm sure both statements are referring to constant current regulator but strangely the advert so much in affection with the classic term which generally is an inductor. Jan 19 '18 at 11:49

The problem is switching power supplies. In my area the radio signals are weak but sufficient as long as they don't have to compete with other RF sources. The new electronic ballasts for fluorescent tubes have very high EMI and turned my radio into a white noise generator. It can't be shielded or filtered because the tube itself is the transmit antenna. The electronic ballasts would have to be redesigned to lower the EMI sufficiently. I tried several brands of direct wire LED. None solved the problem because even these have switching power supplies but they weren't as bad as the electronic ballast.
My under cabinet lights run on 12V. The power supply is a switcher type. It practically wipes out the radio for the whole neighborhood. I'm going to replace it with a big heavy 12V transformer power supply.

The only solution for now is to go back to old fashioned magnetic 60Hz ballasts for the fluorescent tubes. Radios in cars have switching power supplies inside the radio itself and the manufacturers work very hard to make sure they don't interfere. So it can be done. But I have given up on electronic ballasts and LED tubes and am changing my fixtures back to old fashion fluorescent tubes and magnetic ballasts so my radio will work again.

  • You should be able to solve this problem by getting a better ballast that doesn't emit as much RFI/EMI... Mar 15 '18 at 11:45

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