RF from failing fluorescent fixtures and DCS interference?

Fluorescent lighting ballasts are operating @ 20KHz, the MTH DCS is operating @ 900 MHz. Your cordless phone could step on the DCS signal, but I would doubt that the lighting would. Maybe something on the 115 VAC side could be causing your TIU to go whack-a-doodle; assuming the TIU and "failing" lights are on the same circuit.

I doubt the fluorescent lights could generate the RF interference given the broad difference in frequencies -- 900MHz vs. 20KHz, even when you factor in harmonics

I have a basement full of older T12 4' twin tube fluorescent fixtures. 10 of the fixtures are either above or very near to the layout. I have changed the ballast in some of them as they have failed. I have no problems with DCS signals. I haven't had a DCS error in the over two years that the current layout has been in place. The errors I got before that were due to the layout not being properly blocked which has now been corrected.

Remember that the DCS track signal is 3.27mhz, a lot closer than 900mhz.

For 10+ years, I've been using fluorescent lighting 8" above the tracks to illuminate a pair of completely covered freight yards with absolutely no ill effects on the DCS signal.

Test is easy:  turn of the fluorescents and see if problems remain.  I'm not so sure that failing fluorescents do not radiate signals over a wide range of frequencies

Try using regular incandescent light bulbs(floor lamps in a temporary set-up) and see what happens with the signal. As others have mentioned maybe no difference.

Lee Fritz

Thanks for all the replies so far.  By coincidence, a friend who is an EE (electrical engineer), retired from rocketry service, responded to my question by saying failing fluorescents can emit a wide range of RF frequencies, so his advice was simple: get rid of them and try LED replacement tubes that use the same fixture, rewired eliminating the ballast ("Toggled" is the brand I have used before, and will try here.)  FYI the same day I posted, with all fluorescents off, I left a PS2 locomotive live on track for about 5 hours without a hiccup; remote still controlled it without re selecting the engine first.  Not long after turning on the lights had a mystery stop while running down the track.

Will try rewiring a dozen fixtures on one circuit, and running with only those for lights for a good while to see if it cleans up the problem.  Few fixtures, not extremely close to track, might well not do this ( have 17 4 ft 2-tube fixtures in the large train room area); or fixtures maintained better than mine which have old tubes and ballasts and may be emitting a variety of "not normal" RF frequencies.  I have an open mind, and need to try it since there are so many potential confounding variables.  Will add more when the experiment is further along!