4134S 4:1 Unun 5kW for Monopoles, Vertical & Long Wires

  • 9:1 UnUn
  • 1-5-54 MHz
  • 2kW power handling
  • Insertion loss <0.2dB
  • Studs on one side with wingnuts
  • Eyebolt on antenna side
  • Silver plated SO239 connector

Price excl VAT: £113.26
incl VAT: £135.91

1 in stock (can be backordered)


The DX Shop are distributors for Balun Designs

Heavy duty 5kW, 4:1 Unun designed for use with wire verticals, long wires and multiband monopole verticals. Utilizes stacked cores to deliver efficient broadband performance and high power rating across all HF frequencies. Works well with both internal transceiver and external antenna tuners.

This Unun is an excellent match for any of the 43 and 31-33 foot multiband verticals including the S9, ZeroFive, MFJ and DX Engineering vertical antennas allowing the use of full legal limit ++ power.

Although many customers report very good performance using just a single ground rod, the best performance will come from using at least 4+ ground radials or several elevated radials. In a temporary or emergency situation, a single counterpoise can be used when cut to approximately 1/4 wavelength of the lowest operating frequency.

Ununs are intended for use with unbalanced antennas such as verticals and long wires. They will not work with balanced designs such as dipoles or loops and use with a balanced antenna may cause erratic operation and/or damage to the unit.



  Core Material   Custom mix low permeability ferrite by Fair Rite Products for maximum bandwidth.
Cores are coated and sealed for long term durability.
  Winding Type   Stacked cores with single bifilar wire pair wound as 4:1 unun.
Downward impedance transformation by factor of 4. i.e. 200 ohms to 50 ohms.
  Winding Material   Single bifilar winding of 14-gauge Heavy build polyamideimide Allex 240 Winding Wire.
  Windings are inserted into Teflon tubes increasing total breakdown to 10,000 volts.
  Power Rating   1 to 35 MHz – 5kW, 7kW intermittent.  35 to 54 MHz – 4kW.
  Useable Frequency   1 to 54 MHz
  Insertion Loss   Less than 0.1db
  Connectors   SO-239 connectors are silver plated with Teflon insulation.
Studs and eyebolts are 1/4 inch.
  Hardware   All Stainless Steel
  Enclosure Type   NEMA rated 4x marine grade junction box for outdoor installations.
Cover utilizes integral neoprene gasket for weatherproof integrity.
 Dimensions  4x4x2 inches for main body of unit
 Additional Info  Very high efficiency.
Will not heat up or saturate at like many of the “less expensive” designs.