Master Ham Radio Guides & Tutorials

Master Ham Radio Guides & Tutorials: This page brings together in‑depth Ham Radio guides, tutorials, and how‑to articles from DXR Electronics Bits—covering SDR, DRM, propagation, digital modes, receivers, and practical operating techniques, without any news or project‑build posts. SDR, DRM & Reception Tutorials Receive DRM with HDSDR and DREAM Decoder Using RTL‑SDR Build a complete DRM receive chain with an RTL‑SDR […]

DIY Antennas for LoRa and Meshtastic: A Complete Guide to 433, 868, and 915 MHz

LoRa radios offer incredible long-range, low-bandwidth communication—but only if your antenna is up to the task. A poor antenna can limit you to a few hundred meters, while a well-built DIY design can push past 20 km. The best part? You can build proven, high-performance antennas for just a few dollars.

This guide covers everything you need to build your own LoRa antennas for LoRa and Meshtastic 433 MHz (Europe/Asia/amateur radio), 868 MHz (EU), and 915 MHz (North America/Australia). You’ll find exact dimensions, construction tips, band-specific trade-offs, and real-world performance comparisons.

Stock antennas that ship with LoRa modules, Meshtastic nodes, and Helium Hotspots are typically tuned for minimal cost rather than maximum performance. They’re often mismatched to your specific frequency, use cheap materials, and have poorly characterized radiation patterns.

DIY Antennas for LoRa and Meshtastic: A Complete Guide to 433, 868, and 915 MHz: 

Audio compressor for microphone

This circuit diagram illustrates an audio compressor for microphone signals. Its primary job is to even out the volume of your voice, making soft sounds louder and loud sounds quieter, resulting in a more consistent and professional audio output. This is incredibly useful for podcasts, voice overs, amateur radio, or any application where microphone levels can fluctuate.

Audio compressor for microphone

Compact 80 Meter Short Dipole Antenna for Small Spaces

One of the biggest challenges in amateur radio is finding enough space for low-frequency antennas. The 80 meter band is especially demanding because a conventional half-wave dipole requires nearly 40 meters of total wire length. For many operators, that simply is not possible.

Small urban plots, limited rooftop space, nearby buildings, and lack of suitable support points often make a full-size dipole impractical. Fortunately, there are several methods for reducing antenna size without completely sacrificing performance.

This short Dipole antenna for 80 meter is one of the more interesting solutions. By using loading coils placed at carefully selected positions along each arm of the antenna, the overall length can be reduced almost by half while still maintaining respectable efficiency and usable bandwidth.

Compact 80 Meter Short Dipole Antenna for Small Spaces

ATS Mini Firmware Now Supports LILYGO T-Embed SI4732

ATS Mini Firmware Now Supports LILYGO T-Embed SI4732: ATS Mini firmware v2.34 now includes experimental support for the LILYGO T-Embed SI4732 receiver. Here is what the hardware does, how ATS Mini firmware works,