Rated 5.00 out of 5 based on 2 customer ratings
(2 customer reviews)


Common Mode Choke / Noise Suppressor / Line Isolator

The common-mode filter or choke may be one of the best-kept secrets…

  • Covers 3-30MHz
  • Power 5kW *ICAS
  • Choking Impedance 4600-6800 Ohms
SKU: CMC-330-5K Category: Tag:


CMC-330-5K Common Mode Choke / Noise Suppressor / RF Isolator

CMC-330-5K-webThe best Common Mode Choke for 3-30MHz on the market. There is no such product available matching performance of CMC-330-5K. Perfect to cure RFI/EMI problems. Great noise suppressor! It is a cure for noisy locations, reduce the noise floor of your receiver by several S-units instantly.  If you have unbalanced antennas such as OCF dipole or your antennas close to your home, adding one CMC330-5K will greatly reduce RF Interference problems on your equipment and 120/220V wiring inside your home. We do not claim “one size fits all” but actually, we design, measure and make such products. Our CMC-330-5K has huge Resistive values of Common Mode Choking Impedance from 3 – 30MHz, click the chart on the side for actual measurement data.

Unlike other companies, we do not claim unrealistic impedance values or frequency coverage. Most important, the value of CMC-330-5K Common Mode Choking Impedance and its Resistive (Rs) part is always higher than Reactive part (Xs) over the working bandwidth. This parameter, Rs>Xs ensure that our CMC will NOT increase common mode currents as could with inferior coaxial cable chokes.

Only chokes with Resistive (Rs>Xs) CMI- Common Mode Impedance stops and dissipate unwanted RF or noise coming to your equipment for sure.

CMC-330-5K Features:

  • Two large 2.4″ (61mm) Ferrite cores for maximum Choking Impedance and bandwidth.
  • SO-239 PTFE (Teflon) Connectors which produce no impedance bump but the continuity of coaxial cable where the choke is inserted, it helps minimize leakage of RF in multi/contest stations setups.
  •  PTFE (Teflon) insulated coaxial cable used, reduces RF leakage and can handle a lot more than legal power (1500W) in the USA. Rated at 5kW ICAS
  • Enclosure with mounting flanges for easy installation inside or outside the station setup. It has been tested for UV (Ultra Violet) exposure for past eight years with no impact on a material.


 1.85 2900  
  • Zmag-Impedance Magnitude     
  • Rs-Series Choking Resistance      
  • Xs-Series Choking Reactance

CMC-330-5K-CMI- Common Mode Impedance

CMC-330-5K-CMI- Common Mode Impedance

*ICAS = Intermittent Commercial and Amateur Service

Additional information

Product Data


Impedance data

data, data2, data3

2 reviews for CMC-330-5K

  1. Rated 5 out of 5

    Frank EA6ABK

    Hi Dany….
    with CMC-330-5K the problem of RF is over… thank you very much for your advice …. Merry Christmas !!

  2. Rated 5 out of 5


    I’ve had one of these for several years now. Not one issue and the VSWR and load impedance does not change going through these. I’ve been using another company’s product and I don’t think it can handle the power as well as not being well behaved in the VSWR/impedance arena so I’m going to order another CMC330-5k and toss the other device. Thanks guys. Great product.

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