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The _Icom IC-7300_ transceiver, a popular SDR rig, can be readily configured for digital modes like FT8 using _WSJT-X_ software. This guide details the necessary steps, from downloading the correct version of WSJT-X to configuring the radio's USB audio and CAT control settings. It emphasizes a straightforward approach, aiming to simplify the often complex initial setup for new digital mode operators. K0PIR shares his practical experience, outlining the specific menu settings on the IC-7300, such as USB SEND/DPT and USB MOD LEVEL, which are crucial for proper signal modulation and transmission. The resource also covers the integration of WSJT-X's built-in logging capabilities, streamlining the process of recording digital contacts without needing external logging software immediately. This setup allows for efficient operation on various HF bands. Two embedded videos further illustrate the configuration process, providing visual aids for each step, from initial software installation to making the first FT8 contact. The author's method focuses on minimizing common setup hurdles.

This tutorial covers an introduction to RF, wireless, and high-frequency signals and systems, includes explaination of what is RF, why operate at Higher Frequencies, Frequency Shifting through Frequency Mixing.

Clicks are most problematic when we try to copy weak signals next to moderately strong signals. How to recognize them, and how to identify clicks problems

Receive and decode SSTV amateur radio SSTV signals with this small and powerfull SSTV decoder app for Android devices. Requires access to microphone.

This article aims to help promote the proper configuration for having a clean signal on the waterfall to avoid interference to other users and also to vastly increase the effectiveness of your signal.

VLF Time Signal Stations, Station List Compiled by William Hepburn, LWCA

SDR++ is a cross-platform and open source SDR software with the aim of being bloat free and simple to use. Multi VFO, Wide hardware support (both through SoapySDR and dedicated modules), SIMD accelerated DSP Cross-platform (Windows, Linux, OSX and BSD), Full waterfall update when possible. Makes browsing signals easier and more pleasant, Modular design (easily write your own plugins)

Receiving and decoding 433 MHz radio signals from wireless devices

Information related to the G7IZU Radio Reflection Detection page. The detection of meteors, aurora and other phenomena through the use of signals reflected from ionization in the upper atmosphere.

A Dutch website dedicated to weather satellite reception with many documents related to antennas, software and techniques on receiving signals from weather satellites.

Antenna Analyzer plus 500 is a multifunctional measuring instrument, very useful for amateur radio activity. Its size allows you to easily take it for relocation as well. Frequency range: 100KHz - 500MHz. Access directly via WiFi. Includes a dual-channel signal generator

Leader in supplying digital signal processing (DSP) boards, systems, design services and OEM products for the Wireless, Scientific and Defense markets.

This page contains links to a variety of data signals that have been specially recorded. Each file contains a standard test message (the quick brown fox jumped over the lazy dog) repeated twice. The files can help you learn the characteristic sound of various data modes but they can also be used to make sure your decoder is working.

A micro-blog about micro-signals, mostly QRP

The BikeLoop antenna project details the construction of a double magnetic loop antenna optimized for VLF frequencies, specifically around 136 kHz. This innovative design incorporates two orthogonal loops, which significantly enhance reception capabilities. Key construction hints include utilizing lightweight bicycle rims for the antenna structure, making it easy to transport and set up in various locations. The document provides valuable mathematical and electrical insights into the antenna's performance, alongside practical reception tests conducted in the Italian Alps, showcasing its effectiveness in capturing various VLF signals, including Sferics and FSK transmissions. Proper setup is crucial for optimal performance. The project emphasizes the importance of grounding and avoiding interference from nearby electrical sources. The reception tests revealed the antenna's ability to capture a range of signals, demonstrating its practical application for enthusiasts interested in VLF reception and antenna experimentation. Overall, the BikeLoop serves as an excellent starting point for those looking to explore the world of VLF frequencies and enhance their antenna-building skills.

PSK Reporter,is a powerful tool for monitoring your FT8, JT65 or PSK signals around the world. But, even if you are not transmitting on any of these modes it can still be a great propagation tool for determining which bands are open and to where in the world signals from your area are being heard.

Amplitude Modulation (AM) is essentially a mixing process where the audio modulating signal is mixed with the radio frequency carrier

An unique method to listen to QRSS signals is... using an old tape recorder with variable speed

DK8KW Longwave Information Slow-Voice, Transmitting compressed analog Audio Signals on LF

This free app encode pictures in Slow Scan TV SSTV signals. Support the most popular modes Martin 1, Martin 2, Scottie Modes, Robot and Wraase modes. Image editing is even possible with som text overlaying features

A very small receiver converter that can be plugged to the backside of the battery powered portable transceiver FT817 from Yaesu. A high performance receiver for 2.3GHz amateur radio signal

A HF power amplifier with a push-pull of AFT09MS015N. The (small-signal) gain of the amplifier is around 26 dB in the lower HF band and goes down to about 24 dB on the higher end and still around 21 dB at 50 MHz. Its input matching is relatively good at the lower HF and degrades above 10 MHz.

This article discusses how volume reduction can help in the reception of weak signals by reducing the noise level. It is commonly known that reducing the volume also reduces the background noise, and especially in the reception of weak digital signals it can be beneficial

DOMINO DF is a sensitive mode which, due to its incremental frequency keying and thanks to its interleaved multiple tones sets, is easy to tune and is few sensitive to interference and ionospheric effects. Domino faeture a great signal to noise ratio.

Operating on Airplane scattering. Scattering of radio signals by airplanes. An introduction to operating ariplane scattering, using aircraft to redirect RF that would otherwise be lost in space. Antenna Pointing, Doppler Shift/Digital Modes, using digital modes to operate airscatter.

The Icom IC-7300 is a popular SDR transceiver known for its excellent performance in ham bands. However, users have reported issues with reception reliability outside these bands due to ADC aliasing. This phenomenon occurs when the sampling rate of the radio interacts with frequencies outside the intended range, leading to unwanted signals being received. For instance, when tuned between 30 to 36 MHz, users may inadvertently pick up WFM broadcast signals or PMR communications due to aliasing effects. This guide outlines modifications to improve the IC-7300's performance by addressing the low-pass filter design, which is crucial for reducing interference from these unwanted signals. The proposed modifications involve adjusting the low-pass filter on the PA unit to better attenuate frequencies that cause aliasing. Measurements indicate that the original filter design allows significant signal leakage, leading to false receptions. By implementing the suggested changes, users can achieve a notable reduction in unwanted signals, enhancing the overall functionality of the IC-7300. While the modification requires careful soldering, the benefits in performance make it a worthwhile endeavor for serious operators looking to optimize their SDR experience.

This is a very small vertical 160m antenna that fits in the loft of even my small house. It was built as a way of getting a signal out on 160m for local AM contacts, but the local noise level was far too high to allow it to be used at night for this purpose. However, on WSPR it did a pretty good job with WSPR spots from a very long way across Europe being received when running 2.5W out.

An explanation of the different procedures and definitions that are commonly used for blocking dynamic range (BDR) measurements. Dynamic range in general is the ratio between the weakest signal a system can handle and the strongest signal the same system can handle simultaneously without an operator switching attenuators or turning volume potentiometers

Before the advent of satellite communication, maritime communication adhered to an international protocol requiring ships and coastal stations to observe silent periods twice an hour, reserved specifically for emergencies. These silent periods were marked by red sectors on the 500 kHz frequency and green sectors on the 2182 kHz frequency. The 4-second red bars facilitated the manual transmission of the SOLAS distress signal.

Unlock the secrets of RF signal optimization in a presentation covering Balun essentials, diverse types, SWR Analyzer checks, revealing results, Ferrite impedance measurements, and practical applications on feeders and house conductors.

Amateur Radio enthusiasts who are interested in the LF and MF bands may be familiar with WSPR and WSJT JT9. Used as a propagation probe or beacon, WSPR allows very weak signals to be detected, frequently as weak as -27dB SNR.

The Necessary Bandwidth for CW Signals By George Grammer W1DF

Tektronix Signal Generator web site. A Tektronix signal generator can create a virtually unlimited number of signals - analog or digital, ideal or distorted and more.

2 Wavelength ,2 Meter Bi-Square Beam , 5dbd gain. This antennas are very cheeap to build and their radiation pattern is similar to a figure 8 with maximum signal through the loop but they may be used as a near-omnidirectional antenna

Ray-trace radio signals through a realistic three-dimensional ionosphere using Proplab-Pro. This software has been used by the military, researchers, universities and amateur radio operators around the world to assist in determining radio propagation conditions and radio signal behavior. It is one of the most respected and well established software packages for radio engineers and enthusiasts, being actively updated for over 28 years.

Start by getting your audio levels sorted out, Having your levels correct is critical to maximum effectiveness in both TX quality and also for being able to decode signals properly. Guide to Filters and other Rig Settings to optimize your output signal

Article about the essentials of radio signal path loss, its causes and prediction, and its use in radio coverage and wireless survey tools

SDRangel is an Open Source Qt5 / OpenGL 3.0+ SDR and signal analyzer frontend to various hardware TX & RX Software Defined Radio. SDRangel uses sample source plugins to collect I/Q samples from a hardware device.

DXPSK and SMARTPSK are freeware Windows PSK31 software tools capable to send and recive even multiple tracks of PSK31 signals. SMARTPSK is the improved version of DXPSK capable to display up to 25 tracks.

Undertanding the velocity factor in coax cable feed lines. Meaning of the veolcity factor index related to the RF speed of a signal inside the coax cable.

Just a simple signal generator based on ADF4351 module from fleebay allows you to generate one single frequency that can go up or down in 100Khz steps via two push buttons.

How to use AI (Artificial Intelligence) to identify Radio signals using a RTL SDR dongle and Linux (Ubuntu). This solution implement a framework using Keras and TensorFlow to learn and recognize the RF signals.

Free windows application for RF Microwave and Wireless applications. AppCAD is useful for the design and analysis of many circuits, signals, and systems using products from discrete transistors and diodes to Silicon and GaAs integrated circuits. AppCad is a unique suite of RF design tools and computerized Application Notes to make your wireless design job faster and easier

This article introduces an Arduino-based QRP CW Transceiver designed for lower HF bands. The journey begins with the Wotduino, evolving from a keyer to a multi-mode beacon. The development includes a QRP transmitter and culminates in a receiver inspired by Roy Lewallen design. The transceiver, controlled through a control bus features a signal path, modulation, filtering, and adjustable frequency settings. Despite initial testing intentions, successful QSOs on 80 and 40 meters showcase its functional capabilities.

Fans of NIST signals cite benefits including understanding the near-Earth environment

Signal to Noise Ratio, definition and application to Radio Communications. Signal to Noise Ratio (SNR) is a figure of merit that compares the level of a desired signal to the level of background noise.

The _G3TSO_ Mobile Antenna Page details construction and tuning methods for mobile antennas operating across **10 to 160 metres**. The content describes a Hustler-based design, optimized for RF performance and vehicle speeds, featuring centre loading. For optimal operation on various bands, the loading coil placement requires clearance from the vehicle body. Antenna resonance is critical for efficient mobile operation. A mobile antenna's base impedance may be as low as 27 ohms, requiring specific matching to achieve maximum radiation, as a minimum SWR at the transmitter does not always indicate resonance or maximum output. Tuning involves physical adjustment of antenna length to achieve resonance at the operating frequency. The _G3TSO_ page outlines a tuning procedure utilizing a low-power signal source and a field strength meter to identify maximum radiation before impedance matching. Loading coil placement, either at the base, center, or top of the antenna, influences radiation efficiency and mechanical stability for mobile installations. Centre-loaded whips, such as the Hustler design, offer a compromise between efficiency and stability, often for single-band operation. Helically wound antennas, including those for **28 MHz**, may present base impedances around 17 ohms, resulting in a 3:1 SWR at resonance. Low resistance grounding at the antenna base is also specified for optimizing performance and minimizing RFI during mobile operation. DXZone Focus: Mobile | Any | Antenna Tuning | HF

PI-RX is a beacon monitoring program capable of decoding PI4 and showing the performance of the decoded signal

Originally designed by John Kraus, W8JK in about 1940, this antenna has some interesting properties. The W8JK antenna is 2 (Two) centre-fed double-dipole fed by a pair of anti-phase signals. Small size, simple antenna, offer nice performance but need a tuner. Tested in this project from 30m to 6m bands

The PCB can produce a High Frequency RF signal in the range of 1MHz to 12.5MHz using an AD9833 Direct Digital Sequence (DDS) frequency synthesizer. The signal can be modulated with different Weak Signal modes such as WSPR, JT9 and JT65 using our Arduino 5V/16MHz Pro Micro software.