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
Inverted L antenna with radiator and counterpoise for simple installation - choose 80/160 meters and 1.5KW/5KW feed line choke included inside weatherproof enclosure. Separate counterpoise and ground connections
* Complete package - just add coax
* works single band with ease
* can be configured as vertical or inverted L configuration
* Choice of 1.5K, or 5KW PEP rated choke to suit power needs
After many requests we have created a compact, special interface box with internal feed line choke and separate connections for counterpoises (not grounded) and ground connection. The 1:1 choke keeps RF current off the outside of the coax braid and on the antenna where it belongs. The extra choking action also means that the coax feed line will not act as a radiator causing unnecessary RF interference (RFI).
80 M radiator/counterpoise is 70 Feet (you get 1 each) - adjust length to your favorite frequency
160 M radiator/counterpoise is 130 Feet (you get 1 each) - adjust length to your favorite frequency
Antenna is tuned to you favorite frequency by shortening the counterpoise (roll it up or cur length) while keeping the radiator length constant.
Choose 1,5KW PEP or 5KW PEP options.
1.5KW and 5KW are in 4" x 4" x 2" enclosure. 1.5KW is 3 pounds, 5KW is 5 pounds. 2 antenna insulators are included.
ADD CMNF-1500 (1.5KW) or CMNF-5000 (5KW) common mode noise filter at radio end of coax to reduce common mode noise up to 6 "S" units on long coax runs!
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).