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
Off Center Fed (OCF) Antenna Feed Line Choke for 1/4" coax (1.8-61 MHz)
Got an off center fed antenna fed with RG-8X size coax and having feed line radiation (RFI) problems?
This feed line choke will help solve the problem of feed line radiation (which causes RFI to nearby object close to you coax) as well as Improving antenna pattern by preventing your dipole from becoming a tripole
Simple to install as an extension to your existing coax feed line using a female to female barrel connector (available separately).
Install quickly, reduce your coax radiation issues and start working more DX with a better transmission (and reception) antenna pattern.
Also works with single or multi-band loop antennas using a 2:1, 4:1 or 6:1 transformer without a choke.
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).