One of the most popular antennas today is the end fed long wire antenna due to it ease of installation, portability and stealth in various installations. It can be a condo dweller’s only access to the world of ham radio or the best alternative for a backpacking SOTA (Summits on the Air) mountaintop expedition.

The antenna is simple to deploy, folds up easily for transport, and weighs under a pound, yet, with the proper length of wire, can work the 80-10 meter bands easily with the built in antenna tuner of most current day transceivers. You will need several components for a successful deployment of the end fed antenna and these are shown in the diagram below:

Impedance Transformer - End Fed Long Wire Antennas The antenna impedance matching components (BOX “Z” above) to match the antenna impedance to the coax line impedance (usually 50 ohms). For non-resonant end fed antennas, the typical feed point impedance is 300 to 600 ohms and a 9:1 impedance transformer (e.g. 450 ohm average antenna impedance to 50 ohm coax, also know as a 9:1 unun). For do-it-yourself antenna builders, 9:1 impedance transformer information is HERE

With end fed antennas, the coax is meant to radiate as part of the antenna system (serving as the “ground” or counterpoise) and therefore you need to use a Feed line Choke (BOX “FC” above) to suppress the common mode current on the outside of the coax feed line so it does not enter the radio and cause garbled communication.. The Feed line (FC) acts as a stop sign for RF current flowing back on the outside of the coax. The higher the choking resistance of the feed line choke, the less the coax braid RFI common mode current, and the less noise enters the radio. Feed Line choke alternatives are HERE.

Radio System - End Fed Long Wire Antennas The radio station is also a key component of the antenna system and has two functions: transmit and receive. Matching the transmitter to the coax feed line is often done with an antenna tuner and receiver systems should be installed to maximize signal to noise ratio. Reducing receiver noise is critical for weak signal reception and the use of coax noise filters AND receiver power supply lines (AC or DC) noise filters is usually needed for optimum reception. Reducing RFI generated by the radio station (you are the SOURCE of RFI) or received by your radio station (you are the VICTIM of RFI) is an important aspect of radio station operations. Palomar Engineers has many solutions for RFI problems – Click HERE to develop alternative strategies depending on your particular situation.

Want to compare End Fed Antennas? See: End Fed Antenna Secrets (PDF)

The “Bullet” End Fed Long Wire Antenna

The key to end fed antenna success is the matching network interface between the long wire antenna and the coax feed line and feed line choke at the transceiver. Palomar Engineers employs a dual core matching system that offers wide bandwidth (1-61 MHz), 500 watt PEP rating, and a connection for a counterpoise or ground if desired.

The antenna can be used as a sloper, “L” with a vertical section and a longer horizontal section, or as a random horizontal antenna between two trees or supports.

Our network matching network is called the “Bullet” because of it shape and its effectiveness at taking down or contacting distant (DX) stations all over the world under the right conditions. The Bullet uses all stainless steel connectors and a dual core ferrite 9:1 unun for higher power rating then many competitive products.

We sell the Bullet components separately so you can add you own wire type and length or you can purchase a complete antenna system including wire and end insulator.

End Fed Long Wire Antennas

Store/Antenna Products/Complete Antenna Systems/End Fed Long Wire Antennas

End-Fed Long Wire (EFLW) Antennas

Non-resonant, end-fed off-center operation with a 9:1 unun and a coax-braid counterpoise. Place the feed-line choke at the specified distance to “tap” ~400–500 Ω so your tuner only does light touch-up.

An EFLW behaves like an end-fed OCF dipole where the coax braid acts as the other leg. The wire is deliberately non-resonant. The 9:1 unun brings the impedance closer to tuner-friendly range, and the choke position (measured from the unun) sets the effective OCF tap near 400–500 Ω. Do not ground the side stud or the coax braid. Vertical or horizontal bends are fine—tree-to-tree, around corners, or as an inverted-L.

Minimal-tuner method: Leave the wire length fixed. Install the choke at the recommended distance, then slide the choke ±1–5 ft to move SWR dips onto your bands. Add a second SOFLC in series for stronger isolation on 80/160 m if needed.

41 ft • choke ~16 ft 71 ft • choke ~42–50 ft 111 ft • choke ~37 ft 155 ft • choke ~95 ft 173 ft • choke ~80 ft

EFLW – Compact (41 ft, 71 ft)

9:1 unun Choke @ 16–50 ft Coax braid counterpoise

Small-lot & portable. Start with 16 ft (41 ft wire) or ~42–50 ft (71 ft wire) choke distance; slide slightly to trim SWR. Bends okay.

View EFLW Listing Helpful Guides

EFLW – General Purpose (111 ft, 155 ft)

Choke @ 37–95 ft 100 ft coax for 160 m Inverted-L friendly

111 ft → choke ~37 ft. 155 ft → choke ~95 ft (70–95 workable). Use 100 ft coax when targeting 160 m.

View EFLW Listing Helpful Guides

EFLW – Extended (173 ft)

Choke @ ~80 ft 160–6 m with ATU Add 2nd SOFLC if needed

Large lots/acreage. Start choke at ~80 ft; adjust for lowest SWR on low bands. Bends & tree-to-tree runs work great.

View EFLW Listing Helpful Guides

Wire Lengths, Choke Placements & Minimum Coax

Wire Length	Start Choke Distance (from 9:1)	Minimum Coax	Typical Bands (light ATU)	Notes
41 ft	~16 ft	25 ft+	40–6 m	Slide choke ±2–4 ft to trim SWR
71 ft	~42–50 ft	50 ft+	80–6 m	42 ft often helps 80 m
111 ft	~37 ft	50 ft+	80–6 m	Great all-rounder
155 ft	~95 ft (70–95 workable)	100 ft (160 m)	160–6 m	Consider 2× SOFLC for 80/160 m
173 ft	~80 ft	100 ft (160 m)	160–6 m	Strong low-band reach

Which length should I choose?

Pick your yard size and start with the suggested wire + choke distance. You can bend the wire vertically or horizontally to fit trees and structures. Click on size arrow to see options.

Small Yard / Portable / HOA

41 ft → choke ~16 ft → 40–6 m focus.
71 ft → choke ~42–50 ft → adds workable 80 m.
Use 25–50 ft coax. Inverted-L or sloper. Bends are OK (tree-to-tree, corners).

Medium Yard / General Purpose

111 ft → choke ~37 ft → solid 80–6 m with light ATU.
155 ft → choke ~95 ft → 160–6 m capability (100 ft coax).
Try an inverted-L; a short horizontal top section often helps tuning.

Large Lot / Acreage

173 ft → choke ~80 ft → 160–6 m with better low-band depth.
Use ~100 ft coax for 160 m; consider 2× SOFLC for stronger CMC isolation.
Route around trees as needed—vertical and horizontal bends are expected.

Quick-Setup: EFLW Minimal-Tuner Method (open → Print to PDF)

Palomar Engineers

EFLW – 9:1 unun + coax-braid counterpoise • Choke-placement tuning

What the choke does

It stops RF on the outer braid at a measured distance to create the effective OCF tap (~400–500 Ω). That’s what minimizes tuner use.

End Fed Snake - End Fed Long Wire Antennas

Popular lengths & starting choke distances

41 ft → ~16 ft | 71 ft → ~42–50 ft
111 ft → ~37 ft | 155 ft → ~95 ft (70–95 workable)
173 ft → ~80 ft

5 steps

Mount the 9:1 unun clear of metal/wet foliage.
Run wire as sloper, inverted-L, or horizontal—bends are fine.
Measure from the unun and install the SOFLC choke at the distance above.
Run coax to the shack (see minimums in the table; use ~100 ft for 160 m).
Check SWR; slide the choke ±1–5 ft to land the lowest SWR; touch up with ATU.

Tips

Large-OD coax needs fewer turns; for 80/160 m, a second SOFLC often helps.
If the unun/choke warms on long TX, reduce power or duty cycle (digital modes).
Do not ground the side stud or the coax braid—the braid is the counterpoise.

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Shopping resonant end-fed OCFs? See our End-Fed OCF (BULLET Series). Explore OCF Antennas and Loop Antennas. Need deeper dives? Visit our Helpful Technical Guides.