Why We Started RF.Guru

Our origin story and product philosophy—no hype, just physics and field‑proof engineering.

Why We Started

It didn’t start with a business plan. It started with frustration. After years of living with antennas that bent in the first storm, baluns that filled with water, and “wonder antennas” that ignored both physics and their own datasheets, we hit our limit. The breaking point? A trusted active loop failed from water ingress. That was the last straw.

We’d seen too many verticals fold like spaghetti, too many preamps built around museum‑grade transistors, and too many UNUNs wound on the wrong ferrite—if any. Documentation, when it existed, was an afterthought. Support was rare.

So we decided to build it all ourselves—not just better, but right: correct materials, honest specs, complete documentation, and designs for real operators in real weather. What started as a personal mission quickly struck a chord. We weren’t the only ones tired of mediocrity.

RF.Guru was born to be the most honest, technically sound source for high‑performance antennas, baluns, and RF solutions—for operators who care about signal quality, not brand folklore. No magic. Just physics, documentation, and support.

What We’ve Built (So Far)

Launched in April 2022, RF.Guru now ships a complete lineup of receive systems, transmit antennas, matching networks, and station electronics.

RX Antennas & Arrays

• EchoTracer — Active E‑field probe covering 10 kHz–200 MHz with high CMRR and clean wideband performance.
• OctaLoop — Broadband active loop for low‑noise HF reception with useful directionality (optimized for 160–30 m).
• OctaLoop Mini — Half‑size loop (≈60 cm Ø vs 1.2 m) optimized for 80–10 m; compact, apartment‑friendly.
• TerraBooster (Mini / Standard / Maxi) — Shielded loop‑on‑ground (LoG) engineered for urban noise and tough conditions.
• SkyTracer — Capacitive‑loaded, dipole‑style RX antenna optimized for 80–10 m.
• VerticalVortex — High‑performance vertical E‑field probe for 160–40 m.
• PulseRoot — Active Beverage‑on‑Ground (BoG) with automatic termination switching for directional diversity on 160–40 m.
• PyramX (160–40 m) — Compact receive array platform for low‑band directivity and clean pattern control.

TX Antennas

• XentrX (40–6 m) — OCF vertical built for real‑world bandwidth and weather.
• Dual‑Band EFHWs — Optimized transformation ratios for efficient two‑band coverage; most are DX inverted‑L designs (contest‑proven) and are QRO‑rated from 2–4 kW PEP.
• SolidV — Rugged dipoles with straightforward deployment.
• IronWave6 / IronWave9 — UNUN‑fed verticals engineered for robust multiband performance.
• VertX — Multi‑element ¼‑wave vertical system for 20–10 m.
• VertiCore — Our ¼‑wave and 5/8‑wave monoband verticals (modular, serviceable, field‑tough).
• DeltaRex / Solid DeltaLoop Series — High‑integrity delta loops for strong patterns and durability.
• 600‑ohm open‑wire‑fed doublets — Wide‑range, tuner‑friendly classics built to last.
• Monoband Inverted‑V — Open‑wire or coax feed options.
• TermiLoop 160–6 m — Broadband terminated end‑fed loop engineered as a smarter alternative to classic T2FD/BBTD designs. A folded 26 m wire with controlled 20 cm spacing and a non‑inductive termination at a low‑current, high‑voltage node preserves smooth, stable SWR across 160–6 m with less dissipation loss than legacy terminated antennas.

Baluns & Matching

• Wideband baluns for open‑wire lines.
• ATU balun — Purpose‑built for tuner outputs.
• UNUN line — 1:2, 4:1, 9:1; single/dual‑core variants up to 3.6 kW PEP.

RX Enhancement & Phasing

• PolarFLIP — Precision phasing controller; flips LHCP/RHCP and supports elliptical modes. All outputs in parallel for SDR/multi‑op.
• EchoTriad — 3‑element equilateral array controller (EchoTracer/VerticalVortex); low‑angle DX with deep rear nulls, all azimuths live.
• QuadraTus — 4‑element Four‑Square‑style controller (VerticalVortex) for 160/80 m; ultra‑low noise, high RDF, multi‑op ready.
• SignalHub 8 — 8‑port remote RX switch with per‑band/antenna attenuation via LoRa; ideal for SDR and multi‑op sites.

Station Electronics

• Analog hotspot & transceiver — Including a 4G‑enabled variant.
• LoRa tracker — Direct car‑battery hookup.
• ARDF fox transmitters — 2 m & 80 m.
• SilentScout — Passive ARDF antenna for 80 m (stealthy, precise, trail‑ready).
• uPaddle — Capacitive iambic keyer.
• Repeater modules — Modular building blocks.
• 75‑ohm GPS antenna — Multiple outputs for station timing.

About the Team

Joeri van Dooren, ON6URE — Founder
A lifelong radio amateur, RF engineer, and electronics builder, Joeri turns first‑principles theory into gear that performs. He stands for transparency, publishes what we measure, and only ships what he’ll run at his own station.

Jonas van Dooren — Mechanical Design
The reason our products don’t just work—they survive. Jonas brings materials savvy, structural design, and clean 3D execution. Some say we over‑design; we call it hurricane‑proof. When we state you don’t need to guy them, you really don’t.

Jonathan van Dooren — Operations
Logistics, suppliers, admin, and bookkeeping—Jonathan keeps parts flowing, orders moving, and the business as reliable as the gear.

More Than Just Products

Our Knowledge Base hosts 100+ publications across 20+ categories—from EFHW theory and balun selection to RX system design and phasing. We explain not only what works, but why, and where common methods fall short—so you can make better choices, even if you don’t buy from us.

Bottom Line

RF.Guru began with one broken antenna and a promise: no junk, no myths, no excuses. Just solid engineering, honest specs, and support from people who actually get on the air. Not the biggest. Not the cheapest. The most honest and technically sound.