DIY Goodies

Balun 4: 1 for asymmetric dipole

Hello today we will do a balun 4: 1 for asymmetric dipole.

It is time up to me to make an “adult” antenna I stopped at such a calculation.

http://www.cqham.ru/ant85_39.htm

As you can see it requires a transformer that reduces the resistance of the antenna by 4 times from 200 ohms to 50 ohm transformer this name is “Balun”.

I bought toroid rings  http://www.ferrite.com.ua/.

We will need a big one production of the Amidon company T130-2. Wrap 18 windings of PEV 1.0mm according to the following scheme.

We test at a load of 200 ohms.

Everything is normal let’s asseble it PVC pipe case.

Seal upper contacts using rubber linings.

Here the result.

Installed on it’s workplace.