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Ferrite Core Products
Ferrite Mix Selection & Shapes — Choose the Right Core for Your Noise Path
Not all ferrite cores are created equal.
Whether you’re dealing with coax radiation, AC line hash, DC supply noise, or control-cable coupling — the right ferrite mix and shape make all the difference. Palomar Engineers offers a complete line of ferrite rings, snap-ons, slip-ons and bulk packs — each tuned for specific frequency ranges and installation styles.
How to Use This Page
Start by identifying your noise path (coax shield, DC supply, AC mains, control lines). Then choose the correct mix type for the frequency range of the interference, and finally select the shape style (ring, snap-on, slip-on) that fits your installation. Use the table below as your quick guide.
Mix & Shape Selector Quick Table
Ferrite Mix
Effective RFI Range*
Best Shape Types
Typical Applications
Mix 31
~1-300 MHz
Ring, Slip-On, Snap-On
General coax feedlines, HF rigs, antenna common-mode suppression.
Mix 43
~25-300 MHz
Ring, Bead, Slip-On
Higher HF, mixed systems, ballast/LED interference suppression.
Mix 61
~200-2000 MHz
Ring, Snap-On, Bulk Beads
VHF/UHF feedlines, TV cable RFI, high-frequency switching noise.
Mix 75
~0.15-10 MHz
Ring, Large-ID Toroid
Low-frequency suppression; power supply loops, large coax runs, HF amp feedlines.
*Effective ranges are for the interfering signal, not necessarily the antenna or system operating frequency.
Why Mix Choice and Shape Matter
Choosing the correct ferrite mix and shape ensures you block the real noise path in your station: the unwanted common-mode currents riding on your cables. A core that’s too “high-frequency only” may let low-frequency noise through. A case that’s sized too small may saturate under power or not present sufficient impedance. Palomar cores are selected for real-world use in amateur and commercial stations — high choking impedance, wide bandwidth, rugged construction.
- Snap-On: ideal for quick retrofits on existing cables or portable work.
- Slip-On: permanent installation on feedlines, harnesses or control cables.
- Ring-/Toroid-Style: best when you can loop the cable multiple times or wrap for maximum impedance. Great for power or large coax runs.
Installation Tips
- Use the largest inside-diameter core you can fit around your cable or coax — this reduces saturation risk and improves performance.
- Wrap multiple turns if space allows — each turn increases choking impedance significantly.
- Place cores as close as possible to the noise source (e.g., switching supply, antenna feedpoint, or AC panel).
- Even if your system uses high power, a Snap-On kit is often your fastest improvement — then consider adding rings for long-term suppression.
Start Your Ferrite Upgrade
Ready to stop noise and reclaim your signal clarity?
Explore our full line of Snap-On, Slip-On and Ring-Style cores. Browse All Ferrite Core Products ›
Palomar Engineers — Ferrite Application Experts since 1965.
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Ferrite Core Products
Ferrite Mix Selection & Shapes — Choose the Right Core for Your Noise Path
Not all ferrite cores are created equal.
Whether you’re dealing with coax radiation, AC line hash, DC supply noise, or control-cable coupling — the right ferrite mix and shape make all the difference. Palomar Engineers offers a complete line of ferrite rings, snap-ons, slip-ons and bulk packs — each tuned for specific frequency ranges and installation styles.
How to Use This Page
Start by identifying your noise path (coax shield, DC supply, AC mains, control lines). Then choose the correct mix type for the frequency range of the interference, and finally select the shape style (ring, snap-on, slip-on) that fits your installation. Use the table below as your quick guide.
Mix & Shape Selector Quick Table
| Ferrite Mix | Effective RFI Range* | Best Shape Types | Typical Applications |
|---|---|---|---|
| Mix 31 | ~1-300 MHz | Ring, Slip-On, Snap-On | General coax feedlines, HF rigs, antenna common-mode suppression. |
| Mix 43 | ~25-300 MHz | Ring, Bead, Slip-On | Higher HF, mixed systems, ballast/LED interference suppression. |
| Mix 61 | ~200-2000 MHz | Ring, Snap-On, Bulk Beads | VHF/UHF feedlines, TV cable RFI, high-frequency switching noise. |
| Mix 75 | ~0.15-10 MHz | Ring, Large-ID Toroid | Low-frequency suppression; power supply loops, large coax runs, HF amp feedlines. |
*Effective ranges are for the interfering signal, not necessarily the antenna or system operating frequency.
Why Mix Choice and Shape Matter
Choosing the correct ferrite mix and shape ensures you block the real noise path in your station: the unwanted common-mode currents riding on your cables. A core that’s too “high-frequency only” may let low-frequency noise through. A case that’s sized too small may saturate under power or not present sufficient impedance. Palomar cores are selected for real-world use in amateur and commercial stations — high choking impedance, wide bandwidth, rugged construction.
- Snap-On: ideal for quick retrofits on existing cables or portable work.
- Slip-On: permanent installation on feedlines, harnesses or control cables.
- Ring-/Toroid-Style: best when you can loop the cable multiple times or wrap for maximum impedance. Great for power or large coax runs.
Installation Tips
- Use the largest inside-diameter core you can fit around your cable or coax — this reduces saturation risk and improves performance.
- Wrap multiple turns if space allows — each turn increases choking impedance significantly.
- Place cores as close as possible to the noise source (e.g., switching supply, antenna feedpoint, or AC panel).
- Even if your system uses high power, a Snap-On kit is often your fastest improvement — then consider adding rings for long-term suppression.
Start Your Ferrite Upgrade
Ready to stop noise and reclaim your signal clarity?
Explore our full line of Snap-On, Slip-On and Ring-Style cores. Browse All Ferrite Core Products ›
Palomar Engineers — Ferrite Application Experts since 1965.
