The Ferrite Ring Combo Pack is a convenient solution for troubleshooting RFI/EMI from unknown frequencies or multiple frequencies that require multiple suppression mixes. Included in this combo pack are ten 2.4″ OD/1.4″ ID ring toroids as follows:
Mix 75 effective from .15-10 MHz including AM Broadcast band – quantity: 3
Mix 31 effective from 1-300 MHz for general purpose – quantity: 4
Mix 61 effective from 200-2000 MHz for cell phone, WIFI, HDTV, Cable TV interference – quantity: 3
Home Theater/Audiophile RFI Kit
The Home Theater RFI Kits are specifically designed to cure most home theater systems triggered by Radio Frequency Interference problems from AM, FM, CB and Ham radio stations. The kits contain ferrite toroids (“Ring” shaped) for the AC power cord protection and “Snap on” ferrite beads for HDMI, audio, video and speaker cables. The ferrites are selected to eliminate RFI from 1 to 1000 MHz. The ferrites are easy to install, don’t require modification of the protected equipment and work in almost all cases to suppress annoying interference issues.
The ring toroids are useful for AC/DC common mode choking with multiple turns as shown below
 AC Cable on F-240 Toroid – 7 turns |
 DC Cable on F240 – 4 turns |
The ring toroids can also be used on coax or signal lines as shown below:
 RG58 12 turns on FT240 |
 Ethernet Cable on F-240 Toroid – 7 turns |
For RFI/EMI wrap as many turns as possible for higher choking (under 30 mHz).