Electronics and Technical resources from vu3dxr
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 …
Audio processors and speech compressors are important in SSB radio because they can help improve the transmitted signal’s quality. Here are complete resources and links available in the internet connected to Mike Preamplifier/Speech compressors/Speech Processors Dyna Audio compressor Noise Canceling Electret Microphones – WB9YBM Microphone Speech Processor Microphone Amplifier with ALC Audio compression with transistors …
The Really cheap audio compressor circuit diagram from www.freestompboxes.org is a simple, yet effective compressor circuit that can be built with a handful of cheap components. The circuit consists of two op-amps, two LEDs, a LDR, a few resistors, and a capacitor. The first op-amp (U1) is configured as a unity gain amplifier. The input …
A short linear loaded ham radio band HF antenna is a type of antenna that uses linear loading to reduce its physical length. Linear loading is a technique that involves adding parallel conductors to the antenna elements. This increases the antenna’s effective length, allowing it to operate at a shorter physical length. Short linear loaded …
This 80M Trapped dipole antenna is the work of Nadisha 4S7NR, modified by YC0HLE which results are matched at a frequency of 3,845 MHz. This design will be resonant at a frequency of around 3,250MHz to 3,850MHz. Coil inductance = 67.83 µH, made of email wire diameter = 1 mm, diameter of the cocker = …
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 …
Mic Compressor using 3 Transistors is a simple, yet effective, compressor circuit that can be used to improve the dynamic range of a microphone signal. The circuit is made up of three transistors, and it is powered by a 12-volt supply. It was designed by Eko Pramono, a ham radio operator from Indonesia. The circuit …