What Balun / Ferrite ?
We're often asked what type of Balun or UnUn is required for a given situation along with questions about Ferrite Toroids, their mix-types and how many turns are needed.
Much of this information can be found on the respective product pages although this selection page serves as a quick+simple way to get to the best solution for your needs.

Build vs Buy - Why?
Amateur Radio is, after all, a technical hobby that encourages construction where possible - but this isn't always practical with some projects.  You may have to purchase more materials than you need to make it cost-effective, you may not have the suitable tools, space or equipment required to build+test.  Winding 8-12 turns (especially RG142 coax) around a toroid is more of a physical skill than a technical one - and you'll know exactly how after you try it for the first time!

Just what is inside that box?  Does it say?  Does the seller know?  One size doesn't always fit all solutions - and this is why we have a few Balun options plus this page to help you decide.

Baluns and UnUns

• My aerial is a coax-fed Dipole for a single band (but I might use an ATU on other bands) with up to 100-watts
  100-watt 1:1 Balun
   

• My aerial is a coax-fed Dipole for a single band (but I might use an ATU on other bands) and I'm using more than 100-watts
  400-watt Dipole Balun  
   

• My aerial is a Doublet (fed with balanced line) or is a G5RV - I'll be using up to 100-watts across the whole of HF
  100-watt 1:1 Balun
   

• My aerial is a Doublet (fed with balanced line) or is a G5RV - I'll be using up to 1000-watts and/or operating mostly below 15MHz
  400-watt Choke Balun for ATU/G5RV  
   

• My aerial is an off-centre-fed Dipole
  4:1 Current Balun  
   

• My aerial is a full-wave loop
  2:1 Loop Balun  /  4:1 Current Balun
   

• My aerial is a random end-fed wire which I'll use an ATU to deal with - max 250-watts
  9:1 UnUn  
   

• My aerial is a half-wave wire or I have a 20m/40m of garden - max 250-watts
  End-Fed Halfwave Coupler

Ferrite Toroids

Home-brew is a great way to get exactly what you want from a project as well as learning along the way.
We sell a range of ferrite toroids than can be wound with either RG316, RG142, RG58, Mini8 etc to form a Choke Balun.

Our Ferrite Toroid comparison chart may also help you decide:

Here's a line-graph we made using data from Fair-Rite based on a single ferrite bead.  This outlines the typical Resistance of each type of Ferrite mix over a range of frequencies.  This data serves as a simple visual guide rather than a definitive answer to "What type do I need?"...

Although this is quite a basic plot, a longer look will show that a 31-mix offers the best "all-round" solution unless you have a specific frequency range in mind. Bear in mind that with 2.4" ferrites, the Resistance will (hopefully) be >1500-ohms and differences between ferrite types will be greater than the few Ohms you see here!

[this page was last updated Thursday September 21, 2023]