Wall Wart RFI Noise Filter

DC Cable Noise Filter for Large Gauge Wire - 3" ID

DCCF-3

DC Cable Noise Filter for Large Gauge Wire - 3" ID DCCF-3

(4″ OD, 3″ ID hole), RFI Noise Suppression Range: 1-300 MHz

Excellent for large cables or multiple cables – use multiple cores for higher choking. Also useful when you need high turns count for high choking with large cable - works on large gauge DC power cables.

Note: put both positive and negative cables TOGETHER through the filter so that their differential currents cancel but their common mode currents are suppressed.

$44.95 In stock
UPC:Does not apply
Brand:Palomar Engineers
MPN:DCCF-3
Type:New
Country/Region of Manufacture:United States
RFI Range (MHz):1-300 MHz
ID-B (in/mm)::3/76.2
OD-A (in/mm)::4/101.6
Height-C (in/mm)::1/25.4
Weight (oz/gm)::420 grams
Initial permeability::1500
DC Cable Noise Filter for Large Gauge Wire - 3" ID
Wall Wart switching DC power supplies that plug into the AC power line plug and provide DC power to laptops, routers, battery chargers, cell phone chargers, etc are a known source of broadband RFI (a.k.a dirty electricity) that effects many electrical devices including computers, radio receivers, HDTV systems, etc.  In many cases this extra RFI noise effects computer I/O speeds since they have to error correct the information packets many more times due to the noise interference causing packet errors.  A ferrite ring can often increase data throughput by reducing the error correction to normal rates.

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.

RFI-WW Installation

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