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
MAXI-CHOKER Features:
- Uses proprietary Multi-Mix, Multi-Core, Multi-Turn(TM) ferrite technology for maximum choking (up to -48 dB common mode noise rejection) and maximum bandwidth
- Choose 1.5 KW, 3 KW PEP or 5KW PEP for heavy duty digital modes up to legal limit, 50 ohm SO-239 connectors In/Out, 1-61 MHz, usable to 100 MHz
- Suppresses transmitter coax feed line radiation when installed at antenna feed point or reduces common mode receiver "noise" when installed at radio end of coax.
- Available with ground stud/static bleeder option for solving tough RFI issues
- Available with dual stud/wingnut output for ladder line interface
- Works for all coax fed antennas from 1.8-61 MHz (160-6 meters) - excellent for multi-band beams, verticals, dipoles and highly unbalanced off center fed antennas.
- 2-5 times more common mode noise rejection, wider bandwidth and higher power then competing filters (excellent replacement/upgrade in performance for MFJ-915)
MAXI-CHOKER feed line chokes are used to suppress common mode current carried on the outside of the coax braid which is often responsible for receiver noise and RFI in the receiver/transmitter. These chokes are very useful for suppressing RFI common mode current at the antenna feed point, at 1/2 wavelength intervals along the coax feed line and also at the entrance to the radio station. This choke is available with a SO-239 input/output and ground/static bleeder stud (optional) for attachment to a ground rod. Use an isolator every 1/2 wavelength for the antenna operating frequency (include velocity factor in calculation). Use the ground lug option for long coax antenna feed lines (over 1/2 wavelength at the operating frequency of any antenna system in the near field of the coax).
Need a smaller power rating but with same, great common mode suppression? Try our 500 watt PEP rated Mini-Choker HERE
Production Note: Maxi-Choker may be in Black or White color depending upon available inventory at time of shipment.
Production Note: "N" connector models are custom made per order - please allow 2 weeks for manufacturing prior to shipment. You can also get the regular SO-239 version and the optional UHF PL-259 PL259 Male Plug to N Female Jack Straight RF Connector Adapter : UHFMTONF
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).