This week’s issue Radio Waves Weekly — Issue #011leans back toward hands‑on ham radio: practical antenna ideas, audio filters, and front‑end RF tricks, plus a single interesting broadcast‑listener call‑out.
1. BBC Wants Your Shortwave Recordings and Stories
The BBC is preparing a programme about shortwave listening and is asking listeners worldwide to share historic recordings and personal stories. The SWLing Post item explains what they are looking for and how to submit your audio if you logged broadcasts during significant events or from restricted countries.
Details →
https://swling.com/blog/2026/04/bbc-seeks-shortwave-recordings-and-listener-stories-can-you-help/
2. Simple Tuned HF Preselector for SDRs and HF Rigs
HamRadioSecrets describes a low‑cost HF preselector that improves strong‑signal handling and selectivity for general‑coverage receivers and SDRs. The article includes a band‑switched inductor arrangement, variable capacitor, schematic and construction notes, making it a realistic bench project.
Project article →
https://www.hamradiosecrets.com/hf-preselector.html
3. DIY DSP Audio Filter for Radio Hams (Teensy‑Based)
PJRC hosts a feature‑rich DSP audio filter project built around a Teensy microcontroller platform, aimed at improving CW and SSB intelligibility.Besides multiple FIR filter profiles, it also adds extras like Morse decode, USB audio and voice prompts for visually impaired operators.
Build details & code →
https://www.pjrc.com/diy-dsp-audio-filter-for-radio-hams/
4. Passive CW Audio Filter (600–800 Hz) – Video Walkthrough
This YouTube project demonstrates a passive CW audio filter centred roughly around 600–800 Hz, ideal for cleaning up crowded CW signals when your rig has minimal IF DSP.The video shows the circuit in use between a receiver and a small audio amplifier, so you can judge the effect before deciding to build your own.
Video →
https://www.youtube.com/watch?v=L-cL7h90B4g
5. “Let’s Start a Project to Build an HF Preselector?” (EEVblog Forum)
On the EEVblog RF & Microwave forum, a thread titled “Let’s start a project to build an HF preselector?” collects ideas, papers and example circuits for multi‑band preselectors. It is useful as a design playground if you want to go beyond simple single‑tuned circuits and explore higher‑performance units.
Thread →
https://www.eevblog.com/forum/rf-microwave/lets-start-a-project-to-build-an-hf-preselector/
6. Easy‑to‑Build 10 m (28 MHz) Vertical ‘Flowerpot’ Antenna for DX
HamRadioDX outlines an easy 10 m vertical antenna built mostly from coax (a “flowerpot” style), intended for DX on 28 MHz.The article (with matching video) covers dimensions, choke winding and on‑air testing, making it attractive for portable or balcony use when 10 m is open.
How‑to article →
https://hamradiodx.net/easy-to-build-10-meter-28-mhz-vertical-antenna-for-dx/
7. The Antenna That Won Field Day 2025 – 20 m Vertical Delta Loop
At J‑Pole‑Antenna.com you will find “The antenna that won Field Day 2025,” a story and build around a 20 m vertical delta loop used during ARRL Field Day.It chronicles design choices, deployment tricks and on‑air performance, which you can adapt to your own 20 m loop experiments.
Article →
https://www.jpole-antenna.com/2025/07/04/the-antenna-that-won-field-day-2025/
8. Simple Low‑Profile Multiband Antenna for POTA
Ham Radio Outside the Box describes a low‑profile multiband vertical/wire antenna inspired by G3OJV’s “invisible HF vertical,” optimised for POTA‑style outings. It covers using a short radiating element and radials with a tuner to cover several HF bands while remaining visually discreet in parks and public areas.
Project write‑up →
https://hamradiooutsidethebox.ca/2025/09/23/a-simple-low-profile-multiband-antenna-for-pota/
9. Year‑End Compendium of Outside‑the‑Box Antenna Ideas
In a later post, the same blog offers a “year‑end compendium” summarising numerous unusual and experimental antenna ideas tried over the year. It is more of a brainstorm/read list than a single construction article, perfect for sparking ideas for your own 2026 builds.
Compendium →
https://hamradiooutsidethebox.ca/2025/12/15/a-year-end-compendium-of-outside-the-box-antenna-ideas/
10. Extended Lazy‑H – Classic Multiband Wire Design
On vu3dxr.in, the Extended Lazy‑H article revisits a classic multiband wire array from QST 1955 with clear diagrams and modern commentary. It is a good mix of theory and practical notes if you are considering something more directional than a simple dipole.
Article →
https://vu3dxr.in/extended-lazy-h-antenna-a-classic-multiband-wire-design-from-qst/
11. Receive DRM with HDSDR and DREAM Using RTL‑SDR (VU3DXR)
Another vu3dxr.in guide shows how to configure HDSDR and DREAM with an RTL‑SDR for DRM reception on HF, including a simple signal chain and software settings. It is an accessible digital‑mode project that uses inexpensive hardware you might already have in the shack.
Guide →
https://vu3dxr.in/receive-drm-with-hdsdr-and-dream-decoder-using-rtl-sdr/
Want to contribute? Found an interesting circuit, a new SDR software, a helpful radio blog, or breaking ham radio news? Email me or leave a comment below. Your link might be featured in next Sunday’s digest!
