Add a ferrite filter to the digital ballast AC line input and ballast cord output and suppress ugly interference to surrounding electronic devices (yours and your neighbors)! Order 1 set for each ballast.
You get a ring filter (1.4" ID) for the AC power line and a snap on filter (3/4" ID) for the lamp cord. Wrap as many turns as possible on both cables as close as possible to the ballast.
Ballast shown is a Lumatek LK400.
All ballasts in a particular location must have a filter otherwise RFI may not be suppressed to a measurable value. Suppresses RFI in range of .15-10 MHz.
A simple ferrite ring filter on the DC power line can help suppress the RFI noise affecting the victim device or keep the DC power cord from acting as an antenna and radiating RFI into other victim devices. This kit is also useful on laptop computer supplies, routers, cable modems, wireless phone charges, etc.
Installation is quick and easy: Just wrap the DC power cord through the center of the ring filter as many times as you can and reinstall. For best results with long DC power lines, use one at the ring filter at the wall wart end (to prevent the wall wart power supply from using the DC line as an antenna) and another at the DC plug end (to prevent the electronics in the powered device from using the DC power cord as an antenna). Typical installation is shown below:
The filter suppresses RFI in from .1-100 MHz. Inside diameter is 3/4 inch/19 mm.
Since most households and office environments have multiple wall warts we offer the Wall Wart RFI Filter kit in bulk quantity packages.
Known RFI Generators include Roku/Sling-TV power adapter - Interference heard in the AM broadcast band and harmonics. Also many ethernet Cable/DSL modems, cell phone chargers, computer power adapters have the same issue: using the AC or DC side of the power supply as a radiating antenna. RFI solution is to use a linear power supply, change adapters or wall wart ferrite filters