Vee Beam Antenna
A Vee Beam is two long wires run out from a common feedpoint at an included angle, chosen to match the leg length so each wire's own end-fed radiation lobe reinforces along the antenna's bisector — real, textbook long-wire gain from two wires and three supports instead of a rhombic's four. Left unterminated, it's a simpler, bidirectional, resonant antenna fed with ladder line and a tuner; add termination resistors on both legs and it becomes a unidirectional traveling-wave antenna instead, the same tradeoff a rhombic makes.
Why the included angle has to match the leg length
Each leg of a Vee Beam is itself a long-wire radiator, and a long wire's strongest lobes come off at an angle from the wire, not straight down its length — the longer the wire (in wavelengths), the smaller that angle gets. The Vee's included angle is chosen so each leg's off-axis lobe points in toward the antenna's bisector, where the two legs' lobes add constructively. Get the angle wrong for your leg length and the lobes miss each other instead of reinforcing.
Shorter legs -> wider optimal included angle
Same general leg-length/angle tradeoff family as the rhombic
Unterminated (resonant, bidirectional) vs. terminated (traveling-wave, unidirectional)
Without termination resistors, the Vee is a standing-wave antenna: bidirectional off both ends of the V's bisector, resonant, and fed with ladder line into a balanced tuner because the feedpoint impedance is high and reactive. Add a termination resistor to the far end of each leg and it becomes a traveling-wave antenna instead: unidirectional out the open end, broadband like a rhombic, at the cost of real power dissipated in the resistors and two more support points to manage.
- Unterminated: simpler feed hardware, bidirectional, needs a tuner.
- Terminated: unidirectional, broadband, needs termination resistors and accepts their power loss.
How it compares to a rhombic
A Vee Beam needs only two legs and three total supports (the apex plus one at each far end) instead of a rhombic's four wires and four corner supports, making it a genuinely smaller real-estate commitment for a comparable leg length — at the cost of somewhat less gain and a less clean pattern than the four-wire rhombic achieves for the same leg length. It's the practical middle ground between a plain long wire and a full rhombic.
Why height still matters as much as the wire geometry
Like any horizontal HF wire antenna, the Vee's actual DX takeoff angle depends heavily on how high above ground it's strung, not just the leg length and included angle. A Vee sized for a low takeoff angle but hung low won't deliver the low-angle performance the design otherwise promises.
Installation options
- Three-support layout: one center-high support at the apex, with the two legs sloping down to lower end supports — the standard Vee configuration.
- Level flat Vee between three same-height supports: workable where you have three suitably placed trees or masts at similar heights.
- Switchable multi-direction pair: some stations build two Vees aimed at different DX headings, switched at the shack.
| Leg length | Approx. included angle | Typical gain (unterminated) | Notes |
|---|---|---|---|
| 2λ per leg | ~90° | ~7 dBi | Smallest practical size, most forgiving of site limitations |
| 3λ per leg | ~70° | ~8 dBi | — |
| 4λ per leg | ~60° | ~9 dBi | Common size cited in general design references |
| 6λ per leg | ~50° | ~10-11 dBi | Larger real-estate commitment |
Like the rhombic's design chart, these included-angle and gain figures are commonly published approximations, not an exact formula. Check a full Vee Beam design chart or NEC model for your specific height and target takeoff angle before committing to supports and wire.
Vee Beam Antenna Dimension Calculator
Materials for Vee Beam Antenna
Building the Vee Beam Antenna
Getting the included angle right for your leg length matters more here than exact wire length — a resonant trim comes later.
Choose leg length and lay out the V on your property
Use the calculator above to get leg length and included angle for your chosen size, then mark the apex and both far-end support positions.
Erect the apex and end supports
Install the tall center support at the apex and the two lower supports at the far ends of each leg.
Cut and run both legs
Cut two equal lengths of wire to the calculated leg length and run them from the apex insulator out to each end support, maintaining the calculated included angle.
Install the apex feedpoint
Connect both legs to the apex insulator/feedpoint and attach the ladder line for the unterminated (bidirectional) version.
Route the ladder line to the shack
Bring the ladder line in through a dedicated feed-through panel, keeping it clear of metal and household wiring along the way.
Connect to a balanced tuner
Connect the ladder line to a balanced tuner, or an unbalanced tuner through a 4:1 balun rated for the high impedances this design presents.
Tune and verify the pattern
Tune for an acceptable match at the transmitter, then verify the bidirectional pattern favors your intended DX headings along the V's bisector.
| Symptom | Most likely cause | Diagnosis | Fix |
|---|---|---|---|
| Gain seems weaker than the design chart figure | Included angle doesn't match the actual leg length built | Measure the actual angle at the apex against the calculator's value | Correct the angle to match the leg length, or recalculate for the actual angle built |
| Tuner can't find a match on some bands | Feedpoint impedance at that frequency falls outside the tuner's range | Check which band/frequency fails to match | Try different balanced-line taps on the tuner, same troubleshooting approach as a doublet |
| Pattern seems to favor one direction unexpectedly | Unequal leg lengths, uneven support heights, or nearby terrain/structure asymmetry | Compare both legs' length and support height against each other | Correct any length or height asymmetry between the two legs |
Do I need to terminate the ends?
Not for the basic bidirectional version in this guide — termination resistors convert it into a unidirectional traveling-wave antenna instead, at the cost of real power dissipated in the resistors, the same tradeoff a rhombic makes.
How does this compare to a rhombic?
A Vee needs only two legs and three supports instead of a rhombic's four wires and four corners, so it's a smaller real-estate commitment for a comparable leg length — with somewhat less gain and a less clean pattern than a full rhombic achieves at the same leg length.
Why do I need ladder line and a tuner instead of coax?
The unterminated Vee's feedpoint impedance is high and reactive, the same reason a doublet or Extended Double Zepp uses ladder line and a balanced tuner rather than direct coax.
Is this a bidirectional or unidirectional antenna?
Bidirectional as built in this guide (unterminated) — it fires both ways along the V's bisector. Adding termination resistors to both legs makes it unidirectional instead.
How much land does this need?
Less than a rhombic of comparable leg length, but still real acreage — a 4-wavelength-leg Vee on 20m needs roughly 260+ feet of usable straight-line space per leg plus three support points.
Can this cover multiple bands?
Yes, reasonably well through the balanced tuner, similar to a doublet — though the pattern and included-angle optimization are only truly correct at the design frequency you built it for.