Antenna Design Library
Comprehensive documentation for 40+ antenna types. Each antenna includes theory of operation, design calculations, NEC models, construction guides, tuning procedures, and complete worked examples.
Documentation Format: Each antenna type includes 12 detailed documents covering everything from electromagnetic theory to field deployment. Perfect for learning, reference, or actual construction.
Wire Antennas
Horizontally polarized wire antennas for HF bands. Easy to build, effective, and versatile.
Dipole
Half-wave center-fed antenna. The classic reference antenna. 50-75Ω impedance, omnidirectional broadside pattern.
- Simple construction
- Good efficiency
- All HF bands
Inverted-V Dipole
Dipole with sloped elements from single support. Lower impedance (40-50Ω), higher take-off angle, easier to deploy.
- Single support point
- Good for NVIS
- Easy portable setup
Off-Center Fed Dipole (OCFD)
Fed at 1/3 point for multi-band operation. 200Ω impedance, requires 4:1 balun. Works 80m through 10m.
- Multi-band (no traps)
- 40m/20m/15m/10m
- Moderate complexity
End-Fed Half Wave (EFHW)
Half-wave fed at one end. High impedance (2400Ω), requires 49:1 transformer. Excellent portable antenna.
- Single support point
- No radials needed
- Multi-band with tuner
Fan Dipole
Multiple dipoles for different bands fed from common point. True multi-band without traps or tuner.
- True multi-band
- No traps/tuner
- Permanent installation
Folded Dipole
Dipole with parallel conductor. 300Ω impedance (4× standard dipole). Used for driven element in Yagis.
- Broader bandwidth
- 4:1 impedance step-up
- Mechanically robust
Vertical Antennas
Vertically polarized antennas with low take-off angle. Excellent for DX. Requires good ground system.
Quarter-Wave Vertical
Classic ground plane antenna. 36Ω impedance with radials. Omnidirectional low-angle radiation.
- Omnidirectional
- Low angle (DX)
- Needs radials (4-16)
Telescopic Vertical
Portable telescoping whip antenna. Compact, adjustable length. Use with radials or counterpoise.
- Highly portable
- Multi-band tuning
- QRP operations
J-Pole / Slim Jim
End-fed half-wave vertical. No radials needed. Popular for VHF/UHF. Can work on HF with matching.
- No radials
- Vertical polarization
- Simple construction
Flower Pot
Sleeve dipole antenna. Popular for 2m/70cm dual-band. Excellent portable VHF/UHF antenna.
- Dual-band capable
- No radials
- Portable/base station
Loop Antennas
Closed-loop antennas. Full-wave loops are efficient. Small magnetic loops are compact but narrow-band.
Full-Wave Loop
One wavelength loop (diamond, square, or triangle). 100-150Ω impedance. Low noise, directional.
- Quiet reception
- Directional nulls
- Multi-band options
Magnetic Loop
Small (< 0.1λ) tuned loop. Very compact. Requires vacuum capacitor for tuning. Sharp bandwidth.
- Very compact
- Low noise floor
- Apartment-friendly
Cubical Quad
Two full-wave loops (driven element + reflector). Higher gain than Yagi, quieter. 50Ω feed.
- Higher gain than Yagi
- Quieter receive
- Mechanically complex
Delta Loop
Triangular full-wave loop. Can be oriented for vertical or horizontal polarization. Good all-around antenna.
- Versatile orientation
- Good efficiency
- Simple construction
Beam and Array Antennas
Directional antennas with gain. Point at target for maximum signal. Nulls reject interference.
Yagi (3-Element)
Classic beam antenna. Reflector + driven element + director. 6-8 dBi gain. Rotatable for azimuth control.
- Good gain (6-8 dBi)
- Sharp nulls
- Requires rotation
Moxon Rectangle
Two-element parasitic beam. Compact, good F/B ratio. No boom. Easier to build than Yagi.
- Compact design
- Good F/B ratio
- Simpler than Yagi
Log Periodic Dipole Array (LPDA)
Wideband beam antenna. Multiple dipoles in logarithmic spacing. Covers multiple bands without tuning.
- Wide bandwidth
- Multi-band coverage
- Complex construction
Phased Array (2 or 4 elements)
Multiple vertical elements with adjustable phasing. Steerable pattern. Excellent for 160m/80m DX.
- Steerable nulls
- Low-band DX
- Complex feed system
Portable and Field Antennas
Lightweight, compact antennas for POTA, SOTA, Field Day, and emergency operations.
End-Fed Quarter Wave
Simple vertical for portable ops. Needs counterpoise wire. Works with 9:1 or 49:1 unun.
- Very portable
- Quick deploy
- Needs counterpoise
Tape Measure Yagi
Lightweight 3-element Yagi built from measuring tapes. Popular for 2m fox hunting and satellite work.
- Very lightweight
- Low cost
- Great for satellites
Helical Antenna
Circular polarization. Excellent for satellite communications. Adjustable pitch for frequency tuning.
- Circular polarization
- High gain
- Satellite/EME use
Specialized Receiving Antennas
Optimized for reception only. Excellent for listening, SDR, contest support, or learning propagation.
Beverage (Long-Wire RX)
Long wire antenna (1-2 wavelengths) for low-band DX reception. Very low noise, directional. Receiving only.
- Extremely quiet
- Low-angle DX
- 160m/80m/40m
Active Receiving Antenna
Short antenna with amplifier. Compact receiving solution for limited space. Broadband coverage.
- Very compact
- Wide bandwidth
- Requires power
Terminated Sloper
Sloping wire with terminating resistor. Directional receiving antenna. Good for contest operators.
- Directional
- Quiet
- Low-angle DX
Using This Library
Documentation Structure
Each antenna type includes 12 comprehensive documents:
- Theory of Operation - How it works (EM principles, radiation patterns)
- Design Calculations - Formulas and calculations with Python scripts
- NEC Model - EZNEC/4nec2 model file for simulation
- Winding Tables - Loading coils, traps, matching transformers
- Element Lengths - Cut charts for all ham bands
- Feed Point - Location, impedance, balun requirements
- Matching Methods - Networks, transformers, tuning
- Construction - Materials, tools, step-by-step assembly
- Deployment - Installation, site selection, safety
- Tuning - SWR optimization, trimming procedures
- Assembly Procedures - Detailed phase-by-phase guide
- Example Build - Complete real-world project with results
Quick Reference
For experienced builders:
- Go straight to Element Lengths for cut charts
- Check Matching Methods for feed point details
- Review Example Build for bill of materials and cost
Learning Path
For beginners:
- Start with Theory of Operation to understand fundamentals
- Study Design Calculations to learn the math
- Review Example Build before starting your own project
- Follow Construction and Assembly Procedures step by step
Antenna Modeling
Each antenna includes a NEC model file that can be opened in:
- EZNEC - Commercial Windows antenna modeling software
- 4nec2 - Free NEC-2 based modeler (Windows)
- xnec2c - Linux port of NEC-2
Use models to optimize for your specific installation (height, ground type, nearby objects).
Generating Documentation
The complete antenna library can be generated using the Python script:
# Generate all 40+ antenna types
python3 generate_antenna.py
# Generate single antenna for testing
python3 generate_antenna.py --single "dipole"
# Output location
/media/merv/hank/scratch/claude-code/individual/Automation: All documentation is generated from a single Python script. Ensures consistency across all antenna types and makes updates easy.
Contributing
Found an error? Have a suggestion? Want to add a new antenna type?
- Email: merv@energyguy.com
- GitHub: github.com/doflagie
License
All antenna documentation shared under CC BY-SA 4.0
You are free to:
- Use these designs for personal or commercial projects
- Share and redistribute
- Adapt and build upon
Under these terms:
- Give appropriate credit
- Share improvements under same license
73 de Mervyn Martin
Merced, California
U.S. Navy Veteran (CTM, 1983-2004)