To Build a UN-UN you need the following Items
Amidon Ferrite Toroid model T 200-2 ( 0-30 MHz )
Amidon Ferrite Toroid model T 200-6 ( up to 50 MHz )
about 2.4 metres of insulated copper wire 0,75mm
Direction: Fold the 2.4 metres of copper insulated wire in two. Mark the wires' end so to recognize them when the windings is done.
Wind 13 to 19 turns of the bifilar wire ( more turns better response to lower band ).
Connects the wire to the box terminal and the UHF connector ( SO 239 ) see the pics. READY