Knowledge Base: Guides & Technical Resources

Here you’ll find product insights, installation guides, and technical deep-dives organized by category. From explaining why we don’t copy “me-too” designs like coaxial traps and helically wound antennas, to showcasing how our EFHW Inverted-L and EFOC series outperform common alternatives, this knowledge base is your direct line into our design philosophy and proven field performance. Each entry is datestamped so you know when it was last reviewed or updated.

Why We Won’t Offer What Everyone Else Does

• [2025-07-18] We’re Done with the EFHW4010 and EFHW8010
• [2025-07-05] In Praise of Doublets (And Why the G5RV Is a Card House Made of Apple Cake)
• [2025-06-20] Why We Don’t Build a 6:1 UNUN for High Power Applications
• [2025-06-06] Coiled Into Compromise: The Truth About Loading Coils in Shortened End-Fed Antennas
• [2025-05-21] Trapped in a Trap: (Coaxial) Traps in Multiband Antennas
• [2025-05-05] The FD4/Windom Antenna: A Deprecated Classic and Why the EFOC29 Is a Better Choice
• [2025-04-19] Why We Don’t Build Helically Wound Antennas for 40m
• [2025-03-30] No Radial Antennas for Multiband Operation — What Works and What Doesn’t

Engineering Choices: The What, Why & How Behind Our 'Build to Last' Products

• [2025-07-27] Why High Quality Polycarbonate Enclosures
• [2025-07-10] Understanding the Visible Gap on Our Enclosures
• [2025-06-25] Why IP68 Enclosures Still Suck Up Water – And What You Can Do About It
• [2025-06-09] Why Cheap ABS Plastic Is Bad for High Power RF Baluns and Chokes
• [2025-05-22] Why Polycarbonate Enclosures for High-Current RF Chokes
• [2025-05-07] Why Does RF.Guru Use PTFE-Tinned Stranded Copper Wire for Baluns Instead of Enameled Wire?
• [2025-04-20] Why We Don’t Use Resin Potting for Our Baluns
• [2025-04-05] Why Gluing Ferrite Cores with Super Glue or Taping Them Is a Bad Idea
• [2025-03-18] Stainless Steel Type 316: Properties, Benefits, and Applications
• [2025-03-03] Correct Use of RF.Guru Antenna Tuner Baluns
• [2025-02-17] Why We Use a 4:1 UNUN Instead of a 4:1 BALUN
• [2025-02-04] Mounting Flanged Enclosures on a Boom, Mast, or Support Tube
• [2025-01-21] RF.Guru Coating Process: Why It Matters and Why It Can’t Be Rushed
• [2025-01-05] Why We Use ASA for Outdoor Structures
• [2024-12-20] Why Use Tinned Copper Braid to Bond the Balun to the Aluminium Pole
• [2024-12-05] Why We Still Use 600 Ω Open Wire and Not Window Line
• [2024-11-19] High-Voltage Protection in UNUN and BALUN Design
• [2024-11-03] Why We Use Simplified Radiation Models — and Not NEC
• [2024-10-15] Our Logic Behind DX Monoband Antennas
• [2024-09-27] Modeling Antennas with Python: No NEC or MMANA Required
• [2024-09-12] Want to Refer to Us?

Maintenance

• [2025-08-26] Waterproof RF Connectors: Cold-Shrink vs Self-Amalgamating Tape
• [2025-05-12] Copper and Stainless Steel: How to Connect PE Earth the Right Way

Troubleshooting

• [2024-08-30] Common Issues and Their Solutions

Frequently Asked Questions and Their Answers

• [2025-07-02] Are There Any Truly Efficient Multiband 160M-10M or 80M-10M Wire Antennas?
• [2025-06-18] Why Do I Need a Kilowatt-Rated BALUN If I Only Run 100 Watts?
• [2025-06-01] If You Could Choose Only One QRO Multi-Band Antenna, Which One Would It Be?
• [2025-05-14] What Is the Biggest Effect of a Line Isolator?
• [2025-04-28] Why Choose a +45 dB Line Isolator? The Benefits Over Standard Chokes
• [2025-04-12] Why a Line Isolator at the Transceiver and a Balun on a Dipole Are Always Necessary

Wire Antennas

• [2025-07-20] Small-Space HF Wire Antennas – Best End-Fed & OCF Options
• [2025-07-04] HF Antenna Feedline Length Guide – Avoid SWR Problems

End Fed Wire Antennas

• [2025-06-28] Why the EFOC29 Design Outperforms the EFHW8010 and EFLW37 in Multiband Operation
• [2025-06-11] Why the EFOC17 is the Better Choice for 40M to 10M Operation
• [2025-05-27] Why a Near-Resonant Antenna Like the EFOC29 Is Preferable to a Long Wire: EFOC29 vs. EFLW22
• [2025-05-09] The EFLW51: A Quick-and-Dirty Compromise for 160m
• [2025-04-23] The EFLW37: A Quick-and-Dirty Antenna for 80m Local Work
• [2025-04-08] EFHW, EFOC, and EFLW Explained: Which End-Fed Antenna Is Right for You?
• [2025-03-22] Why an EFOC Is the Smarter Choice for Camper Installations
• [2025-03-06] EFHW vs. EFOC: Two Voltage-Driven Antennas, Two Smart Solutions

End Fed Half Wave Wire Antennas

• [2025-07-08] Why RF.Guru Pushes Dual-Band EFHW for High-Power (3kW–4kW)
• [2025-06-29] Why We Do Not Use Compensation Capacitors on Our EFHW Antennas
• [2025-06-13] Why We Primarily Use Full‑Wave and Half‑Wave End‑Fed Antennas
• [2025-05-31] The FullHalfWave Series (EF FHW): Dual Half‑Wave EFHWs Reimagined for Real‑World DX
• [2025-05-15] Comparing 80/40 Meter EFHW Antennas: Inverted L vs. Sloper/Flattop for DX and NVIS Operations
• [2025-04-30] Performance of Our 81 m EFHW as a Sloper for 160 m and 80 m
• [2025-04-12] Inverted‑U Configuration for the EFHW16080
• [2025-03-29] Why Your EFHW Is Eating Your Signal — And the EFOC Isn’t

Inverted‑L EFHW antennas

• [2025-07-24] Comparing a 15 m and 20 m Mast for a Dual‑Band 160/80 m EFHW Inverted‑L
• [2025-07-06] Why RF.Guru Recommends Only Inverted‑L for 160/80 m and 80/40 m (68–70:1 Transformers)
• [2025-06-21] Why an EFHW Inverted‑L for 160/80 m Outperforms a 20 m Vertical with a Tuner
• [2025-06-07] Why an EFHW Inverted‑L for 80/40 m Outperforms a 10 m or 13 m Quarter‑Wave Vertical
• [2025-05-26] These Two Inverted‑L End‑Fed Antennas Will Crush DX on 160/80 m and 80/40 m
• [2025-05-08] Why the EFHW Inverted‑L for 160/80 m Outperforms a 20 m Vertical on 80 m
• [2025-04-19] Vertical Section and Feedpoint Height in Inverted‑L EFHW Antennas
• [2025-04-04] EFHW Inverted‑L: How Clay Soil Affects Your Antenna
• [2025-03-20] Lowering SWR on 160/80 m Inverted‑L EFHW by Sloping the Wire
• [2025-03-04] Lowering Feedpoint, SWR Doesn’t Change on a 160/80 m Inverted‑L EFHW
• [2025-02-16] Tuning a 160/80 m EFHW Inverted‑L for SSB DX
• [2025-02-01] EFHW 160/80 Inverted‑L for OT8M Contest Station: 77.5 m with Low Feedpoint Height
• [2025-01-12] EFHW 160/80 Inverted‑L for F4VUX: Performance on Challenging Ground in the Ardennes

Inverted‑L EFOC antennas

• [2025-06-02] Feedpoint Height Guidelines for the Inverted‑L EFOC17/29

Vertical antennas

• [2025-08-02] Grounding the IronWave Series: When and How to Do It
• [2025-08-01] Balcony-Mounted Verticals: Radial Layout Makes or Breaks Performance
• [2025-07-30] Why the RF.Guru VertX Fan Vertical Radiates Smarter Not Just Bigger
• [2025-06-17] VertiCore 5/8th: A More Efficient Antenna for 10–12 m Band
• [2025-06-01] VertiCore 1/4th: The Reliable Workhorse for 15, 17, and 20 m

Loops

• [2025-08-05] TermiLoop 160–6 vs EFHW & BBTD — Which Is the Better All‑Band Option?
• [2025-07-14] TermiLoop vs Other Terminated Antennas: A Practical Comparison
• [2025-06-27] TermiLoop 160–6 vs. 7‑Band EFHW with Compensation Capacitor
• [2025-06-08] Why Our 61° and 120° Delta Loops Crush DX — Even From Just 6 m Height
• [2025-05-19] DeltaRex on a 65‑Meter Rooftop: Turning a Loop into a DX Weapon

RX — OctaLoop

• [2025-07-26] Why an Octaloop Is Superior to a Square or Circular Loop Antenna
• [2025-07-09] Height vs. Performance: Optimizing the OctaLoop Active Magnetic Loop Antenna

RX — VerticalVortex

• [2025-06-30] Mounting the Vertical Vortex
• [2025-06-15] Why the VerticalVortex Excels at Low‑Angle DX Reception (But Not NVIS)
• [2025-05-28] Why the 6 m / 35 mm VerticalVortex eProbe Works for 160–80 m Reception

RX — PulseRoot

• [2025-07-01] PulseRooth vs Traditional Full‑Length Beverage

RX — Phased Arrays

• [2025-08-03] Installing the EchoTriad Phased Array System for 30 m to 10 m and 160 m to 40 m Multiband Reception
• [2025-07-21] EchoTriad RX Array Spacing Calculator (45° Hybrid)
• [2025-06-24] Spatial Phasing, Not Just Delay Lines — Why RF.Guru Builds RX Arrays with Fixed Hybrids
• [2025-06-03] EchoTriad: 6–12 dB Better SNR Than a Yagi — Because Hearing Is Believing

RX — Antennas Installation guides

• [2025-05-02] How to Tune the PulseRoot 100 with a 9 V Battery and 2 Resistors

EndFed Antennas Installation guides

• [2025-07-03] EFOC29 Antenna Installation Guide
• [2025-06-16] EFOC17 Antenna Installation Guide [NL]
• [2025-05-29] EFOC8 Antenna Installation Guide
• [2025-05-11] EFOC29 — Get 80 m and 30 m Under Control: Practical Tips for Better SWR
• [2025-04-26] Optimizing the EFOC29 for 160 m–10 m Operation with Additional Radials
• [2025-04-09] General High‑Power EFHW UNUN (49:1 / 68:1 / 70:1) — Installation & Safety

Doublet Antennas Installation guides

• [2025-06-05] Mounting a 44 m Doublet on a 16 m Pole with 16 m 600 Ω Open‑Wire Feedline
• [2025-05-17] Mounting a 31 m Doublet on a 10 m Pole with 16 m 600 Ω Open‑Wire Feedline
• [2025-04-01] Mounting an 80 m Doublet on a 16 m Pole with 16 m 600 Ω Open‑Wire Feedline

UNUN and BALUN Installation guides

• [2025-03-25] General UNUN — Installation & Safety Instructions (PDF)
• [2025-03-12] General BALUN — Installation & Safety Instructions (PDF)
• [2025-02-24] LINE ISOLATORS — Installation & Safety Instructions (PDF)
• [2025-02-10] ANTENNA TUNER BALUN — Installation & Safety Instructions (PDF)

PCB Products Installation guides

• [2024-12-14] 2023‑P‑811 PowerPole Power HAT for Raspberry Pi — Installation Guide

Electronic Ham Radio Devices Installation guides

• [2025-01-18] µPaddle Compact Capacitive‑Touch Iambic Paddle — User Manual

Hotspot, Transceiver, Receiver and Repeater modules Troubleshooting

• [2025-02-06] Troubleshooting Man‑Made Noise on Hotspot, Transceiver PCBs and Devices (VHF/UHF)