Question 1

How much power will a balun made from an FT140-43 handle?

Accepted Answer

The maximum power has to do with the permeability of the material and the field strength your coil generates. If you exceed the maximum power, you won't damage the unit, but will incur losses as the ferrite material is saturated and cannot support an increased magnetic field.

I'm using a single FT140-43 for a 49:1 UNUN (16 gage wire) running at 10 watts max for portable field operations, and it works very well for this application. According to my calculations, it could handle up to 37.5 watts CW or 60 watts SSB. If you need more power, I would recommend stacking two FT140-43s, and you could double the power, i.e. 120 watts SSB / 75 watts CW. If you're looking for even higher power, I would look at using an FT240-43 or FT240-52 core.

Question 2

What is the country of origin?

Accepted Answer

Faur-Rite Brand (the manufacturer) FT140-43 are manufactured in China.

Question 3

Where do you put these , on the wire or somewhere else ? I see some say wrapping the wire , do you run it in and out of the ring ?

Accepted Answer

Yes you run it in and out of the ring as many times as it can.

Question 4

Can this be used for long wire unun balun? some sites suggest t-130 hence the question.

Accepted Answer

Yes. I wrapped mine with #12 antenna wire as a choke between my elevated radials and earth ground. Major improvement to my signal strength. K5AE

FT-140-43 Ferrite Toroid Core - Amidon | 43 Material

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