Electronics and Technical resources from vu3dxr
Class E – AM Transmitter A Class C AM transmitter is a type of high-efficiency, solid-state transmitter that is popular among amateur radio enthusiasts. It is known for its simplicity, affordability, and efficiency compared to other types of transmitters. Unlike Class E’s switching operation, Class C amplifiers operate in a more “on or off” manner. …
Noise Canceling Condenser Microphone Noise Canceling Electret condenser microphones are a great choice for noise-canceling applications due to their small size, low power consumption, and high sensitivity. They work in conjunction with active noise cancellation circuitry to create a more peaceful listening experience. Electret condenser microphones (ECMs) can be very effective for noise cancellation when …
Microphone compressor using two transistors Microphone compression is a useful tool that can help you to achieve a more consistent and polished sound. By reducing the gain of the loudest parts of your signal, compression can help to even out your volume levels and make your voice sound more upfront in the mix. It can …
Dynamic speech compressor or simply audio compression is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds, therefore reducing or compressing an audio signal’s dynamic range. Compression is commonly used in sound recording and reproduction, broadcasting, hearing aid, live sound reinforcement, and in some instrument amplifiers. There are …
One watt AM transmitter This is a simple two stage transistor ‘one watt AM transmitter’ for the HF band which gives around 1 watt in output. You can use easily available transistors like BD139, SL100, 2N3866, 2N2219 or a 2N3553 in the final stage. The output with transistor 2N3553 is approx. 1.8 watt @ 12 …
A simple series modulated AM QRP HF transmitter is a type of radio transmitter that uses amplitude modulation (AM) to transmit audio signals over a high frequency (HF) radio band. It is designed to be low-power and simple to construct, making it a good choice for beginners or those who want to build a QRP …
The OXO QRP HF transmitter is a simple, low-power CW (continuous wave) transmitter designed by George Burt, GM3OXX. It is a single-band transmitter that can be built to operate on any of the amateur radio bands from 160 to 20 meters. The transmitter is built around a few standard transistors and a crystal oscillator. It …
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 …
The circuit shown is a microphone speech compressor built around operational amplifier LM324. This amplifier circuit exhibits gain and also continually adjusts that gain to maintain a constant amplitude output signal, regardless of the amount of signal coming from the microphone. The microphone is coupled to the LM324 Operational Amplifier IC which has 4 separate …