The First Thing New Ham’s Often Ask: What Is An UnUn? And What Is It Used For In Antennas?

The Short Answer Would Be That an UnUn Is a “UN balanced to UN balanced” matching transformer. It is used for non-resonant verticals like 43 foot or 33 foot Or Wire antennas like an End-Fed 1/2 Wave Multiple Length Wire Antenna.

Here Is a 250 Watt Home-Brew That I Made In about an Hour.

Part List:

1 X FT240-43 Ferrite Toroid Core 43 Material (Mouser Electronics)

1 X SO-239 UHF PANEL JACK S/CUP SO-239 (Mouser Electronics)

12 Gauge Insulated Solid Copper Wire

No. 6 Screws/ Nuts/ Washers/Wing Nuts And Ring Connectors

1 X Mica Capacitors 100pF 500V 5% (Mouser Electronics)

1 x 4 in. x 4 in. x 2 in. PVC Junction Box (Home Depot)

1 x 1/2 in. Liquidtight NM 90-Degree Connector (Home Depot)