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Below is a diagram of a 4.1 balun. Both the 4.1 and 1.1 can be wound in the same manner as you would using toroids but using ferrite rods. This diagram along with the photo on the first balun page should give a good enough idea of how to build a 4.1 balun.
![IMG00001[1].gif](images/IMG00001[1].gif)
I have made 4.1 baluns on both toroids and ferrite .My first attempt at a 4.1 toroidal balun was using a T130-2 with 18 bifilar windings of #20 enamelled wire . This gave slightly less than a 4.1 transformation. Using the same gauge wire and using 15 bifilar turns on a 6cm piece of ferrite rod gave me a better transformation. It wasn't critical for the application i wanted the baluns for but it was interesting to see the difference between the two.Experimenting with the turns on the toroid balun may give better results. For higher power the toroid would be the better option but for me using 5 watts the ferrite would do just fine. One tip i would give is to make the balun for a higher power rating than you actually need as you may in the future want to up the power of your station. I tend to simply stick with qrp in mind as i cant't see me wanting higher power anytime in the future.
Ferrite baluns
Below are two ferrite wound baluns. The top balun is a 4.1 using 15 bifilar windings of 20 gauge enamelled wire on a 6 cm rod. Below is a 1.1 current balun using again 15 bifilar turns on 6cm rod. These cost pennies to make up and seem to work well.You could make a box full of these for the same price as postage costs alone on a shop bought one.
4.1 balanced transformer
Below is my balanced 4.1 transformer i have made for my loop antenna. Its built using 2 stacked T130-2 toroids with 20 bifilar turns of #20 enamelled wire on each toroid. The paper tags are to keep track on the windings.
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