A Handful of tips and Pointers in Sourcing Cores for Baluns and Transformers

Sourcing Cores for Baluns and Transformers

We’ve collated just a handful of the very many online outlets of ferrite cores for baluns and transformers. We’d highlight the word ‘FERRITE‘ as iron powder cores are only really suited for a handful of applications. For most projects, a ferrite core will be the order of the day especially for higher power variants.

There’s more info here on how to construct your own 1:1 Balun/Choke balun [50 ohms to 50 ohms] and a 4:1 balun transformer [200 to 50 ohms]. The later being good for matching a loop antenna.

A 1:1 Choke Balun using an Amidon ‘K’ [240-52] type ferrite ring with 12 turns of RG-303 premium PTFE coax. Note how the winding transposes and flips under the core at the halfway point. This reduces capacitance between the windings.

QuBits: UK based. Good for the amateur although the range is fairly limited. eBay sales.
Ham Goodies: UK based aimed towards essential ham radio related components.
Mainline Electronics: UK based. Long standing UK name. Limited range. eBay sales.
Sinequanon: UK based. Lots of pro-grade hard-to-find NOS [New Old Stock] RF components at great prices. Online shop with easy ordering. Only a small limited stock of ferrites.
Ferrite Shop: EU based [Netherlands] offer all the main ferrite cores for the amateur operator including cable clamps, toroids and cores. Easy online ordering.
RF Micowave: EU based [France] good selection and other professional RF components. Easy online ordering.
Mouser: US based but national satellite sites. Big international company. Many large cores and typical ‘ham-cores’. Great range. Similar to RS but way better. Worldwide delivery.
Fair-Rite: US Based manufacturer. B2B site. Probably the world’s best know manufacturer. No online ordering
Amidon Associates: US Based with a huge range. Online ordering. Data sheets available.
Magnetics: US/Hong Kong based. B2B site. No online ordering. Great range. Lots of unusual bespoke cores.
Palomar Engineers: US based. Excellent ham range including baluns and tech advice.
Micrometals: US based. B2B site. No online ordering. Big range.
Ferroxcube: US Manufacturer. B2B site. Lots of technical info for designers.
Worldlist of Ferrite Manufacturers, courtesy of Walter PE1ABR
Toroids.info: A good data source with technical info on many common balun and transformer cores. Three great F/L/C/Z online calculators.