END FED 4B short mk3

Code: 307/CU2
In stock

End Fed EFHW wire antenna for bands 7-14-21-28 MHz, fed at the end by coaxial cable, total radiator length 12,5 m, mk2 version - movable massive radiator mounting

Detailed information

Product detailed description

Wire HF antenna with radiator fed at the end.
The antenna is fed by a 50 ohm coaxial cable.
The transformer circuit is mechanically designed to allow high variability in different mounting conditions. 

mk3 version - movable solid mounting of the radiator, mounting of the antenna with clamps on the pipe up to 50 mm diameter

The radiator is single, end-fed and electrically designed in ½ lambda length or multiples thereof.
It connects to the transformer circuit.
The usable bands are according to the selected emitter.
4B short - 7-14-21-28 MHz - emitter length 12,5 m, includes coil
4B - 7-14-21-28 MHz - emitter length 20 m, does not include coil
5B short - 3,5-7-14-21-28 MHz - emitter length 24 m, includes coil
5B - 3,5-7-14-21-28 MHz - emitter length 42 m, does not include coil

- 7-28 MHz bands
- emitter length 12,5 m
- coil included
- antenna cable according to the selected variant
- transformer element END FED
- compensation capacity 100 pF / 10 kV
- power load 300 W PEP max (on digi, FT8 etc. max 100 W)
- weight 1 kg
- the mounting is variable thanks to the mechanical design of the Unun
- PL connector (UHF)
- stainless steel fasteners

The transformer circuit can be mounted variably in different placement conditions - using plastic or metal pull-tabs on a pipe, railing, mast, etc., it can just be hung or screwed to a surface.

The antenna should be supplemented with a Link Insulator, connected as close as possible to the antenna.
This will prevent shell currents and interference (RFI).

Depending on the specific mounting design, the use of an antenna tuner on some bands should be considered. The quality of the ground, surrounding objects and environment, the height of the ends of the radiator, the shape of the radiator extension (horizontal, angled, cranked, etc.) have an influence.
Optimal mounting conditions are: horizontal at 10m height, power supply with a coaxial cable of the length of the impedance repeater to the lowest band used. Impedance repeater = ½ lambda x truncation factor (for the specific cable used)