4:1 Unun for Multiband Verticals and Random Wires – 1kW

This is a unun (unbalanced to unbalanced) transmission line transformer designed to match 200Ω to 50Ω intended for use only with unbalanced antennas such as long wires and verticals multiband.

With 9.5m (31feet) to 13.1m (43feet) you can have excellent match of 5/8 wave antenna’s vertical length, angle of radiation is just 16 degrees making it an even better DX antenna.

– This concept is used by commercial branches such as ZeroFive antenna, S9 antenna ….

Concerning a counterpoise, you can use just a single ground rod or single ground radials or many, when cut to approximately 1/4 wavelength of the lowest operating frequency will make the antenna more efficient and easier to adjust.

“If you want to work DX, but you just can’t afford a tower and beam. You’ll be very pleasantly surprised at its performance.”

Type:                                                  4:1 Current Balun

Frequency:                                        1 – 52Mhz

Input Impedance:                            50Ω

Output Impedance:                          200Ω

Typical insertion loss:                     Less than 0.05 dB

Power Handling (CW/AM/SSB): 700w /500w/1Kw

Core Type:                                         FT240-43 by Fair-rite® Co.

Wire type:                                          Enamel copper wire 1.6 mm (AWG 14)

Insulation type:                                PTFE

Package Contents: You get what you see – Photo 2 is an illustration of a setup unit – unit does not come with wires.

FT240-43 core by Fair-rite® winding with Enamel copper wire 1.6 mm

Assembled and tested