June Starts with Chokes, Roofs, and the Sound of Solar Inverters Waking Up
By the start of June, the antennas are back in full use, the weather is less forgiving, and every weak assumption in the station starts getting louder. The roof gets hotter, the enclosures get tested, the feedlines settle into their real environment, and somewhere nearby an inverter decides the bands were too quiet.
That makes this a good moment to focus on the parts of RF that look simple until they are built outdoors: common-mode chokes, transformer losses, metallic roofs, vertical behavior, and measurement methods that feel convincing right up until they measure the wrong thing.
So this issue is about exactly that: what still holds once the system leaves the bench, meets weather, and has to work in the real world.
When a Common-Mode Choke Test Jig Measures the Jig
A timely reminder that a measurement setup can quietly become part of the result.
If the jig dominates the behavior, the choke never really got its turn to speak.
π https://shop.rf.guru/pages/when-a-common-mode-choke-test-jig-measures-the-jig
The 50 Ξ© / 150 Ξ© Common-Mode Choke Myth on Multiband Antennas
A neat-looking rule that breaks down once multiband antennas stop behaving like one tidy textbook load.
π https://shop.rf.guru/pages/the-50-ohm-150-ohm-common-mode-choke-myth-on-multiband-antennas
Why S21 Can Look Right for Chokes but Still Be Wrong
Another example of how a familiar instrument reading can feel convincing while still answering the wrong question.
π https://shop.rf.guru/pages/why-s21-can-look-right-for-chokes-but-still-be-wrong
Transformer Losses: A Reality Check
Broadband transformers are compromises, not miracles.
This piece brings the discussion back to heat, stress, geometry, and actual operating conditions.
π https://shop.rf.guru/pages/transformer-losses-a-reality-check
The Paper That Made Baluns Stop Being Magic
A welcome look at the point where transformer folklore gave way to clearer RF thinking and better engineering language.
π https://shop.rf.guru/pages/the-paper-that-made-baluns-stop-being-magic
Transmission Losses Are Not Mismatch Losses
Two losses, two mechanisms, one confusion that still refuses to die.
π https://shop.rf.guru/pages/transmission-losses-are-not-mismatch-losses
Outdoor RF Enclosures Built for Weather and Reliability
Summer is when pretty boxes become real test subjects.
A good enclosure is not just about keeping rain out β it is about survivability, serviceability, and RF sanity.
π https://shop.rf.guru/pages/outdoor-rf-enclosures-built-for-weather-and-reliability
Current Distribution in Inverted-L Antennas
A useful way to stop talking about inverted-L antennas as shapes and start talking about them as current systems.
π https://shop.rf.guru/pages/current-distribution-in-inverted-l-antennas
Vertical Antenna on a Metal Roof
Sometimes a metal roof helps. Sometimes it dominates. Sometimes it changes the question entirely.
π https://shop.rf.guru/pages/vertical-antenna-on-a-metal-roof
Why a Log-Periodic Antenna Is Less Pesky Around a Huge Metallic Roof
Not immune, not magical β just less easily pushed around by nearby metal than many simpler antenna types.
π https://shop.rf.guru/pages/why-a-log-periodic-antenna-is-less-pesky-around-a-huge-metallic-roof
When 1/4-Wave and 5/8-Wave Verticals Are Similar β and When They Are Not
Another case where the slogan version of antenna theory hides the conditions that actually decide the result.
π https://shop.rf.guru/pages/when-1-4-wave-and-5-8-wave-verticals-are-similar-and-when-they-are-not
A Near-Resonant Off-Center-Fed Antenna Is Still a Real Antenna
Because βnot perfectβ is not the same thing as βnot valid,β even if some antenna arguments pretend otherwise.
π https://shop.rf.guru/pages/a-near-resonant-off-center-fed-antenna-is-still-a-real-antenna
Bad Solar Inverters
A seasonal classic: the sun comes out, the panels wake up, and the HF bands suddenly sound like an apology note from EMC compliance.
π https://shop.rf.guru/pages/bad-solar-inverters
When Antenna Claims Outrun Antenna Physics
A useful antidote to the kind of marketing language that sounds bold precisely because it skipped the hard parts.
π https://shop.rf.guru/pages/when-antenna-claims-outrun-antenna-physics
Meshtastic, MeshCore, 868 MHz, and the Ham Radio Trap
A timely look at where experimentation, regulation, and amateur-radio framing do not always line up the way people assume they do.
π https://shop.rf.guru/pages/meshtastic-meshcore-868-mhz-and-the-ham-radio-trap
Prefer watching measurements and hearing the reasoning instead of inheriting another summer myth?
Mark covers many of the same themes with calm explanations, practical demonstrations, and a very low tolerance for magical RF thinking.
π Watch the featured videos from our collaboration
If this issue leaves you slightly more suspicious of neat choke graphs, slightly more respectful of weatherproofing, and slightly less impressed by claims that arrived without current paths, loss analysis, or context β good.
That is a very healthy way to begin June.
73,
Joeri β ON6URE
Founder β RF.Guru
https://rf.guru/