DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
The Tools category brings together both hardware and software that make your radio life easier: audio helpers, shack utilities, measurement aids, and digital tools that support building and operating. You’ll find projects like microphone compressors and RF indicators, along with curated lists of PC and web utilities for circuit design, PCB layout, simulation, logging, and on‑air operating
Simple audio compressor for SSB HF Radio rigs An audio/speech compressor is a device that reduces the dynamic range of the audio signal. This means that it makes the loud parts of the signal quieter and the quiet parts of the signal louder. This can be useful for SSB HF radio rigs because it can […]
NE555 based Microphone amplifier IC NE555 or commonly known as 555 is an IC that is well known among electronics practitioners as an IC for timers, and can be used to form monostable or bistable multivibrator circuits. But not many know that the 555 IC can also be used as an audio signal amplifier. By […]
This article presents a simple, low-cost audio compressor circuit designed to stabilize microphone signal levels. It reduces dynamic range by softening loud sounds and boosting weak ones, improving clarity and intelligibility. Built with basic components, it suits amateur radio and DIY audio setups, offering consistent output without complex or expensive hardware.
SSM2167 audio processor for Baofeng Mic enclosure Mic gain is barely adequate on the µBITx transceiver since there is no Mic Gain control. It would also be helpful to not only provide mic gain control, but to add compression in order to boost the average power output.The SSM2167 is a powerful audio processor that can […]
This project uses an SSM2167 IC as a complete microphone preamplifier with built-in compression and noise gating to improve uBITX transceiver audio. It boosts mic gain, reduces dynamic range, and suppresses background noise, resulting in clearer, louder, and more consistent transmitted speech.
This article explains how to build a low-cost ribless programming cable for Motorola GM360, GM338, and GM300 radios. It uses a USB-to-TTL adapter, RJ45 connector, and a diode to enable direct serial communication without a RIB unit. The guide covers wiring, setup, and software configuration for reliable radio programming.
Decoding the Motorola GM300 model number provides critical details about the radio’s specifications, such as frequency band, power output, channel capacity, and more. The GM300 model number typically follows Motorola’s standard convention, with the first six characters indicating the base model and the subsequent characters specifying features like RF power, frequency range, channel spacing, and […]
The GM300 series radios are line of two-way radios manufactured by Motorola Solutions. They are popular choice for amateur radio operators due to its features, performance, and affordability. GM300 is also a very durable radio. It is built to withstand the elements and can handle even the most demanding conditions. Similarly, the Motorola GM338 is […]
DIY Programming cable for a Motorola GM 300 series two-way radio To make a DIY programming cable for a Motorola GM300, you will need the following materials: A USB-TTL adapter An RJ45 Ethernet connector A standard silicon signal diode, such as the 1N4148 An Ethernet cable. Once you have gathered your materials, follow these steps […]
VK3YE’s AGC circuit for ubitx An ubitx AGC board is a circuit board that can be installed in a ubitx transceiver to provide automatic gain control (AGC). AGC is a feature that automatically adjusts the gain of the transceiver’s amplifier to maintain a constant audio output level, regardless of the strength of […]