RF Touch lamps are RF-operated devices that often cause, or are susceptible to, EMI problems. They have a free running oscillator that is very broad and rich in harmonic energy. This oscillator is hooked up to a touch plate that changes the frequency of the oscillator when a hand is placed near the plate. Unfortunately, this plate also acts as an antenna, radiating some of the energy of the oscillator, or picking up nearby radio signals. When the former happens, it can interfere with other services. When the latter happens, the circuitry inside the lamp reacts the same way that it would when the plate is touched -- the lamp changes states from "off" to "on".   Although cases of moderate interference can sometimes be cured by using a "brute-force" type AC-line filter and/or a common-mode choke, most cases will require internal modification to the lamp. For a number of different reasons (you may be blamed if anything EVER goes wrong with the lamp or house wiring) you do not want to perform this modification on equipment that is not your own. Remember -- house AC power is dangerous. These modifications must only be performed by qualified service personnel!

• Touch Lamp RFI Cured ...And Again! (65,536 bytes, PDF file)
  QST May 1993, p. 78
  Technical Correspondence
• Hints and Kinks - Low-Pass Filter Cures Touch-Lamp Interference (65,536 bytes, PDF file)
  QST April 1995, pp.72-73
• Additonal Hint and Kink items

The Lutron FAQ Page provides information about light dimmers, including RFI.