What: Pepco – Radiofrequency Interference Issues
When: September 15, 2000 8:00 AM
Our guest speaker, Mike Martin, is THE interference investigator for PEPCO (Potomac Electric Power Co.) He provides commercial and residential customers with resolution assistance for RFI and TVI issues. It is common for folks to assume that a problem is caused by the power company or by local broadcasters but that is not always the cause.

Mike has made his presentation to our chapter before, but his knowledge and methods have developed significantly since then. Through PEPCO and his own company, RFI Power Services, Mike provides training and inspection services to power and telecom utilities, cable companies and legal concerns nationwide. He is a fulltime employee of PEPCO, one of the few utilities to provide such services on a full time basis. During our meeting, Mike offered tips on being able to detect the onset of problems, such as arcing, before they become major problems such as the ignition source of a building fire.

Here's Mike's "How To" for locating RFI or TVI in the home. He assures the skeptics among us that with his technique, he can find almost any problem in a short amount of time. If you have questions, contact Mike at RFI@Pepco.com.

All steps should be performed while interference is active!

  1. Go to your main circuit breaker or fuse panel with a battery powered AM radio tuned between stations so all you hear is the offending noise. (If at night or in an enclosed room, be sure to have a working flashlight)
  2. If the noise is present and corresponds to the disturbing interference, shut off all power to your premises by turning off the MAIN circuit breaker or equivalent enclosed device. (DO NOT ATTEMPT TO REMOVE CARTRIDGE FUSES or OPERATE EXPOSED or OPEN-TYPE DISCONNECTS IF PHYSICAL CONTACT WITH ELECTRICAL CIRCUITS IS AT ALL POSSIBLE.) If the noise on the AM radio stops while the power is off, the source of the interference is within your own residence.
  3. Restore the main circuit breaker. Don't forget to reset clocks after the interference source is located.
  4. Assuming the noise stopped while the electric was off, you can now locate the circuit supplying the power to the noise source. While monitoring the battery powered AM radio as before with the noise present, turn off and on the individual circuit breakers one at a time until the noise stops. Leave off the breaker that stops the noise.
  5. You must now determine what has been turned off by going from room to room, if necessary, checking outlets, appliances, and lights for the absence of electricity. The offending noise will be something on this circuit. Turn the breaker back on and wait for the noise to return.
  6. With the noise back on and using the AM radio to monitor, return to the area of the noisy circuit and unplug everything on this circuit one at a time until the offending device is found.
Things most commonly found to cause interference are:
  • Door Bell Transformers
  • Electric Blankets
  • Heating Pads (of all kinds)
  • Recessed Ceiling Lights
  • Furnace Control Circuits
  • TV Top Amplified Antennas
  • Aquarium Heaters
  • Screw In Photocells
  • Low Energy (screw in) Florescent Lights
  • Touch Control Lamps
  • Clean Air Machines (table top and furnace type)
  • Light Dimmer Controls
These devices, when causing interference, are in violation of Federal Communications Commission rules, regulations and are a nuisance to you and your neighbors. It is important for your own benefit to have the offending device repaired or replaced to insure normal safe operation. Most radio and television interference sources are arcing. This arcing will get hot and could create a fire hazard. Your interest and assistance is sincerely appreciated. For more information about RFI & TVI contact:

PEPCO's Interference Investigator, Michael C. Martin
Tel 301-967-5230 Pager 301-767-1362 E Mail RFI@PEPCO.com

Please include with all inquiries: Name, Address, 10 digit Phone