The Poor-Man’s Transmitter: Building a Simple AM Radio Beacon from Vintage Electronics, uses a clever arrangement of 4011 CMOS gates to create AM Radio Beacon
audio
The audio category collects everything related to sound in your shack: microphone preamplifiers, speech processors, tone generators, practice oscillators, test signals, and audio troubleshooting guides. You’ll find circuits like simple 2N3904 mic preamps for uBITX, audio peak limiters, speech processors, UJT code practice oscillators, pink noise generators, and sine‑wave sources, all tuned for amateur‑radio and hobby use
NJM4558 Audio Compressor Circuit: Complete Schematic & Build Guide
The NJM4558 audio compressor represents one of the most reliable and widely-used integrated circuits in professional audio applications. Furthermore, this dual operational amplifier IC has become the cornerstone of countless audio compression circuits due to its exceptional performance characteristics and versatility. The NJM4558 audio compressor circuit shown in the schematic demonstrates a sophisticated approach to […]
Ham Radio Repeater Toneburst Module circuit
Ham Radio Repeater Toneburst Module generates a precise 1750Hz toneburst lasting 0.5 seconds, essential for accessing UK and European amateur radio repeaters.
Audible Continuity Tester for for Electronics Testing
This audible continuity tester uses a simple oscillator IC to generate a tone when a closed circuit is detected. Powered by a 1.5V battery, it provides instant audio feedback for testing wires, fuses, PCB traces, and connections, making troubleshooting faster and hands-free.
Build Your Own Simple Sine Wave Oscillator
This simple sine wave oscillator uses a transistor-based phase-shift network to generate a clean periodic signal, then amplifies it with an LM386 for usable output. It runs on a 9V supply and suits audio testing, tone generation, and learning oscillator fundamentals
TL071 Audio Compressor Circuit
This TL071 audio compressor circuit uses a single-supply design with a TL071 op-amp as a voltage-controlled amplifier to manage audio levels. It includes input coupling, peak detection, and RC timing networks to control compression, delivering stable, low-noise dynamic range control for audio and radio applications.
Audio compressor for microphone
This microphone audio compressor uses an LM324 op-amp with multi-stage amplification, diode-based gain control, and buffering to regulate signal levels. It smooths volume by reducing loud peaks and boosting weak input, improving clarity for voice, recording, and radio applications with a stable 12V supply
Can You Use MXR Dyna Compressor for SSB Radio?
This article explains why the MXR Dyna Comp, a guitar compressor pedal, is not suitable for SSB amateur radio use despite being a compressor.
It points out key issues like impedance mismatch, since guitar pedals expect high-impedance inputs unlike microphone or line-level signals used in transceivers. It also highlights that the pedal’s frequency response and controls are designed for musical audio, not narrowband voice signals used in SSB.
Microphone compressor using LM1458
The LM1458 is a dual operational amplifier (op-amp) that finds applications in audio amplification and other circuits. Let’s explore how you can create a simple Microphone compressor using the LM1458. To get greater transmitting performance from your ham radio transceiver, we need to keep the modulation level constant, regardless of your voice level. With the compressor […]
Condenser Mic audio amplifier – DIY Guide
The compact, low-cost condenser mic amplifier described here give good-quality audio of 0.5 watts at 4.5 volts,used in walkietalkies, low-power transmitters