Description
CMC-154-3K Common Mode Choke / Noise Suppressor / RF line Isolator
This is the one and only true Common Mode Choke / RF line Isolator for 1-54 MHz on the market. It is the only product with over 7000 Ohms of CMI on 50MHz while maintaining a Resistive part of CMI for more than 50MHz of the frequency spectrum, actually, it has the same values all the way up to 85MHz.
- Multi-Zs™ Technology
- Perfect to cure RFI/EMI problems.
- Great noise suppressor!
- Common-mode attenuation is up to 39dB max. (measured in 50 Ohms systems)
It is a cure for noisy locations, reduces 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 CMC154-3K 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-154K has huge Resistive values of Common Mode Choking Impedance from 1.8-54MHz, 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-154-3K Common Mode Choking Impedance and its Resistive (Rs) part is always higher than the Reactive part (Xs) over the working bandwidth. This parameter, Rs>Xs ensures 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.
See the video of CMC’s in action at AC0HF station
CMC-154-3K Features:
- SO-239 PTFE (Teflon®) Connectors which produce no impedance bump but a 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 can handle a lot more than legal power (1500W) in The USA. It is rated only to 3kW because of the cable limit at the 50MHz.
- The enclosure is UV stable and could be used outside.
Use it as BALUN for YAGI, HEX beam, G5RV/ZS6BKW, Dipoles, etc.
Common Mode Impedance data Chart
| Frq.(MHz) | Zmag(Ohms) | Rs(Ohms) | Xs(Ohms) |
| 1.85 | 2500 | 1200 | 2200 |
| 3.7 | 3700 | 2600 | 2500 |
| 7 | 4800 | 3800 | 2800 |
| 10.1 | 5900 | 5250 | 2750 |
| 14 | 6500 | 6300 | 1700 |
| 18.1 | 6500 | 6500 | 700 |
| 21 | 6400 | 6400 | 360 |
| 24.9 | 6250 | 6250 | -18 |
| 28 | 6150 | 6150 | -140 |
| 50.1 | 7400 | 7300 | -1100 |
- Zmag-Impedance Magnitude
- Rs-Series Choking Resistance
- Xs-Series Choking Reactance
*ICAS = Intermittent Commercial and Amateur Service
Gennaro A. –
Perfect. It works well and like declared
Frank Lucia –
Not used yet.
Gerald Cornell –
Michael Donohue –
Andrew M. –
Seems to do a great job keeping the reflected power away from my equipment. Have had no problems.
Larry Staker –
ALAN C. –
Well worth the $$$. Well built, weather-proof & extremely rugged. Performs as specified and does the job!
Steve Graves –
Andrew M. –
It works as expected 🙂
Robert L. –
Anonymous –
Warren Greenberg –
I was having RFI problems and when I rebuilt the antenna after hurricane Milton, it solved the problem.
Mark B. –
Angelito J. –
Phil –
Philip –
It helped to remove some unwanted noise from the coax
Jeffrey Wyke –
I bought 2…..one placed at antenna, and another placed in shack after Tranceiver. The chokes removed several S-Units of noise, and perform very well. I recommend this product!
Timothy –
Anonymous –
The ferrites worked.I also have 2 of your EFHW’s. Had issues with mine initially but after trying several things including shortening coax,it seems to work better now. Fine tuning instructions may help some people like me,who prefer to buy antennas than build.
JAMES AGUIAR –
JAMES AGUIAR –
James W. –
Solid performance, rugged build – none better!