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Receiving **GOES-16** and **GOES-17** weather satellite imagery requires a specific hardware and software configuration, detailed in this practical guide. The author outlines the necessary components, including a Raspberry Pi, an RTL-SDR dongle, a suitable LNA with SAW filter for 1.69 GHz, and a parabolic grid antenna. This setup enables direct reception of high-resolution weather data, a fascinating aspect of amateur radio satellite operations. The installation process begins with preparing the Raspberry Pi, followed by updating the system and installing essential dependencies like `git`, `build-essential`, and `cmake`. A critical step involves compiling and installing `librtlsdr` from source, ensuring proper driver setup and blacklisting conflicting DVB drivers. The guide then walks through testing the RTL-SDR dongle to confirm device recognition and troubleshoot common issues like USB power or driver installation problems. Finally, the instructions cover cloning and building `goestools`, a software suite essential for processing the satellite signals. This compilation, while time-consuming on a Raspberry Pi, is crucial for decoding the raw data into usable imagery. The guide concludes with the initial steps for creating the `goesrecv.conf` configuration file, preparing the system for active satellite reception.

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

PSK Reporter provides a real-time visualization of amateur radio digital mode reception reports, aggregating data from a global network of monitoring stations. This platform is particularly useful for operators utilizing modes such as FT8, FT4, and PSK, allowing them to observe signal propagation paths and assess their station's reach. The interactive maps display reception reports, enabling hams to analyze band conditions and optimize antenna performance for various frequencies and times of day, aiding in understanding ionospheric conditions. Operators can filter reports by callsign, band, mode, and time, gaining insights into specific propagation events or evaluating the effectiveness of their transmit setup. The data collected helps in predicting optimal operating windows for DX contacts across various digital modes. Philip Gladstone is the contact person for comments and discussions regarding the system.

Ucchino is an Italian manufacturer of electronic cirucits inclunding Digiham amateur radio USB interface for digital modes, morse code oscillator, filters and RF protectors

Utilizing snap-on ferrite cores and practical insights, the author enhances their shack's cleanliness against electromagnetic interference. With meticulous experimentation and installation, they improve noise levels across HF bands, reflecting on the effectiveness of their filter in minimizing common-mode disturbances. Updates underscore ongoing refinement and cautionary advice for optimal filtering and radio reception amid changing RF environments.

An home madek Audio CW Filter made simply using SMD Components

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.

DXLook is a free, web-based propagation platform that delivers comprehensive, real-time insight into HF and VHF conditions directly from any modern browser. It aggregates live spots from PSK Reporter, WSPRnet, RBN, and DX Cluster, complemented by NOAA space-weather metrics such as SFI, K/A indices, and geomagnetic alerts. Integrated VOACAP predictions allow practical "theory versus reality" comparisons, while the interactive world map with filters, gray line, and grid overlays enhances situational awareness. With no installation or maintenance required, DXLook provides a convenient, accurate, and accessible solution for everyday operating and propagation analysis.

If your multiple transceiver station is suffering of intrastation interference, this handy and inexpensive band pass filters and help you. QST article Sept 1988

Home made 40 meter transceiver project. The receiver is a Progressive Receiver with a few modifications. The Transmitter is a modified MFJ Cub circuit. Includes schematic and circuit diagrams for Receive Input Filter, 3-Pole 500 Hz Cohn Filter and 7 MHz Double Tuned Bandpass Filter

This multiband transverter project features power output at 13,8V 50MHz 15W, 70MHz 10W, second harmonic < 65dBc. Single N connector of antenna, suitable for a dual band Yagi. Article include Block Diagram for Dual Transverter and low pass filters

Online antenna parts store, providing many accessories for amateur radio antenna homebrewing. Boom joiners, aluminium parts, elements clamps, filters, ferrites, fasteners, plasti caps, dipole elements. Based in UL

Icom IC-R9500 Professional Receiver with 5 roofing filters, 48 kHz DSP

DX Cluster spots represented in a google map, for 10m 6m 2m bands taken from the VE7CC DX Cluster. Some filtering options are available.

Amateur Radio goodies for not only the Shack, but also a range of outdoor/portable kit. Ferrite toroids, RTL SDR, Un-uns and Baluns for antennas and RF Filters. Based in the UK.

This document details the construction of a multi-band end-fed antenna, suitable for situations with limited space for larger antennas. The design utilizes a 1:49 to 1:60 impedance transformer to match a half-wave wire antenna fed at one end. Compared to a traditional dipole, this antenna resembles a highly unbalanced Windom antenna with one very long leg and a virtual short leg. The design eliminates the need for radials but relies on the coax cable shield for grounding. The document recommends using at least 10 meters of coax and installing a common mode filter at the entry point to the shack for improved performance.

This document details the construction, programming, and operation of a modular WSPR transmitter. The transmitter utilizes an ESP8266 NodeMCU, an SI5351 synthesizer with a TCXO for stability, and selectable low pass filters. Construction involves soldering headers, components, and assembling filter module. The ESP8266 is programmed via the Arduino IDE, requiring library installations and code modifications, including network credentials, callsign, and frequency . The transmitter is powered by USB or Vin terminals and its frequency is selected by jumpers and software settings. The document also covers FCC restrictions and how to use the WSPR network

A step by step guide to install the NS Roofing filter into the Yaesu FT-2000

How to replace IF filters on a Yaesu FT 857. This document explains how to desolder old deteriorated filters and replace with brand new ones.

1-watt 17-meter cw transmitter that was originally done about 10 years ago as a club project for RAMS, the Radio Amateur Megacycle Society. It uses a VXO, rather novel at the time. It also uses a bandpass filter at the output rather than the usual lowpass

Transmission lines have many uses other than simply transferring RF power from one point to another. Impedance matching, baluns and filters are probable the most common of these.

The Quarter-wave stub can be used for many purposes. If it is left with an open end it can be used as a notch filter to attenuate certain frequencies. A quarter wave length of a transmission line can also be used as an impedance transformer, to know more about the Quarter-wave impedance transformer

Worldwide Map of shortwave transmitters. Based on shortwave schedule database, this website let you serarch using filters for broadcasts schedule and at the same time to diplay the transmitter map.

Operating from Banana Island, Sierra Leone (AF-037), the 9L2019 DXpedition by F6KOP and a ten-operator team used the callsign 9LY1JM from January 9-21, 2019. This detailed report covers the logistical challenges, including securing visas and licenses with local assistance from Mark 9L1YXJ and Gregory of Dalton’s Guest House. The team deployed monoband quarter-wave verticals on the beach and two Beverage on Ground (BOG) antennas for Europe/Asia and the USA, operating four stations simultaneously. Technical hurdles encountered included high tides submerging antennas, requiring repositioning, and persistent QRM between closely spaced stations, mitigated by doubling filters. CW signal irregularities at 30-32 WPM were resolved by PC and WINTEST restarts. A significant FT8 logging bug was identified and corrected with on-site software. Despite these issues, the team logged over 4,000 QSOs in the first 24 hours, averaging 5,000 QSOs daily, with a peak of over 6,000 in one day. Propagation varied, with excellent 160m conditions on January 12 yielding over 750 QSOs, and a later four-hour opening pushing the 160m total past 1,600. High bands were challenging due to low solar activity, but mid-bands provided intense pileups and rapid continent-wide contacts. The DXpedition concluded with nearly 50,000 QSOs, including a successful school QSO with Collège Doisneau de Sarralbe (57), managed by F1ULQ and F6KFT.

If RF noise threatens to take your hobby away, this could be probably a good solution to reduce or even eliminate RF Noise.

A simple superheterodyne receiver (3.5–30 MHz) for amateur radio achieves stable SSB-CW reception using modern BJTs, an AD831 mixer, a 6-pole quartz filter, and Seiler oscillators. Designed with high IF (4.5 MHz), compact AM-FM variable capacitors, and modular resonant circuits, it ensures selectivity, image rejection, and stable tuning. Built in a copper-lined wooden case, it features practical assembly techniques but lacks advanced features like AGC or S-meter. Effective on basic antennas, it achieves global reception.

How to install INRAD filters on the FT 847

Microwave Filter Company is a leader in the design, development and manufacture of high quality passive electronic filter products in the 5 Hz to 50 GHz frequency spectrum.

This is a power amplifier project for a RF 600W 1.8 MHz to 70 MHz linear amplifier including a Low Pass Filter. Projects includes schematics, pictures, PCD design, fans details, note on PA ferrite chokes and assembling instructions

Pro Audio Engineering (PAE) supplies products for broadcast and amateur radio applications. The company manufactures heatsinks for _Elecraft_ **KX2** and **KX3** transceivers. PAE also produces AC power supplies for HF transceivers, remote power relays, and Ethernet relays. Machined products from PAE are manufactured in the **USA**. PAE distributes _Fair-Rite_ Mix 31 ferrite snap-it cores and toroid cores in various internal diameters. The product inventory includes commercial monitoring antennas, UQUI transformers, ULP AC power filters, and 3M conductive adhesive copper tape. Offerings also include the AM1 Portable Antenna Mount System. Pro Audio Group, LLC holds the copyright for the company as of 2024 DXZone Focus: _Elecraft_ | _Fair-Rite_ | Heatsinks | Ferrite Cores

This PDF article introduces a series of dual-tuned bandpass filters designed for input tuning in amateur band receivers. Developed by Stefen Niewiadomski, these filters feature 50-ohm input/output impedance and can be cascaded for improved roll-off outside the passband. The designs use readily available TOKO coils, with taps on the tuned winding for matching input circuits with impedances around 1k ohm. The inductors are core-tuned, with average inductance values provided for easier matching to other inductors.

An online database featuring current and historical weather balloons, complete with a fully searchable archive that can be filtered by launch site. The integrated map shows both the current and historical trajectories of radiosondes, from their launch points to their final landing positions.

Custom built high and low power power band pass Filters, low band triplexers, triplexers and diplexers

Zenith Tracker offers real-time satellite tracking, pass predictions, and radio hardware integration for ham radio operators. The platform includes an interactive world map showing satellite positions, footprints, and ground tracks, as well as a polar radar visualization for detailed pass analysis. Users can view upcoming passes, set filters, and receive notifications. Integration with CSN Technologies S.A.T Hardware and QTRigDoppler allows for automatic radio control, antenna tracking, and transponder management. The platform also offers APRS message interface, grid square-based location input, and API integration for rover activations. Zenith Tracker is recommended for both general users and those needing advanced hardware integration.

Over 15 amateur radio bands, from 160m to 70cm, are supported by the _DXTRON_ web cluster, providing real-time DX spotting information. This service integrates directly with the _QRZCQ_ API, allowing users to monitor activity across various modes including CW, Phone, Digi, RTTY, SSTV, and SAT. DXTRON displays critical spot data such as timestamp, spotter callsign, frequency, mode, DX call, and remarks, along with geographical details like Grid, DXCC, ITU, CQ zone, continent, and country. Developed by _DO5SSB_, DXTRON v1.42 offers a user-friendly interface for filtering spots by band and mode, catering to both casual DXers and serious contesters. The platform is designed for accessibility, providing a clear overview of current propagation conditions and active stations worldwide. This web cluster is a practical tool for hams seeking to identify rare DX, track contest activity, or simply observe band conditions. Its reliance on the QRZCQ API ensures a consistent flow of up-to-date spotting data, making it a reliable resource for real-time operational awareness.

Hamradio_copilot is an open-source tool designed for DXers and contesters who need real-time situational awareness. It is ideal for operators who want to visualize propagation trends instantly rather than scrolling through raw text streams of cluster spots. Rally acting as a copilot for your station, this tool transforms raw data into actionable intelligence. By visualizing Signal-to-Noise Ratios (SNR) across different bands, it helps operators make quick decisions on which band to prioritize or where to point their antennas, effectively showing not just who is on air, but where the propagation is currently open from your location. This is a fantastic information for avid contesters. The software aggregates data from two primary services: - Reverse Beacon Network (RBN) via Telnet. - PSK Reporter via MQTT feeds. It processes this data to generate a comprehensive HTML report featuring SNR heatmaps and statistical breakdowns by ITU Zone. Users can filter data by specific zones or country codes (ADIF), analyze historic time ranges, and optionally integrate solar weather data. The complete source code is available on GitHub, allowing for community customization. It is written in Python and uses SQLite for data management.

Replacing two ceramin filters of a Yaesu FT-857 by desoldering and soldering new ones.

Hostilog, developed by DF1LX using Python 3.5 and PyQT5, is a logging application designed for high-speed QSO data entry, achieving rates of 300–400 QSOs per hour from handwritten logbooks. The software prioritizes keyboard input, minimizing mouse usage for efficiency. It incorporates a cluster window with RegEx filtering capabilities and facilitates UDP transfer of QSO data to _DXkeeper_ from the _DXLab Suite_. The program supports basic rig control via _Hamlib_, with configuration examples provided for radios like the TS-590S using `rigctld`. Hostilog can process 50,000-line ADIF files in under 10 seconds and includes features for combining and sorting ADIF data. While primarily a Windows application, it runs under _WINE_ on Linux, with specific notes on Ubuntu compatibility. Recent updates, including a version from August 28, 2024, address bugs and improve UI, with documentation available in both German and English.

TFilter is a free online tool for designing linear phase, optimal, equiripple finite impulse response (FIR) digital filters. It utilizes the Parks-McClellan algorithm implemented in JavaScript. Users can specify the sampling frequency, desired number of taps, passbands, and stopbands to generate a filter. An example configuration is provided for easy testing.

This article explores the nuanced design challenges of Band Pass Filters (BPF) in radio receivers, balancing low insertion loss, high stop band rejection, and narrow bandwidth. The focus is on the "Series-Trap, Shunt-C" topology, resonator count impact, and meticulous layout design for superior stop band performance across various frequency bands

This page, authored by VU2ESE, delves into the sBitx, a Software-Defined Radio (SDR) designed for homebrewers. The content covers the hybrid SDR circuit, software, user interface, hacking/modifying the sBitx, performance, and more. It explores the various components of the sBitx, including the exciter, filters, amplifiers, digital circuit, and modems. The page aims to provide information and guidance for hams interested in building their own SDR. Readers will learn about the capabilities, features, and adaptability of the sBitx, making it a valuable resource for DIY radio enthusiasts.

Spotty leverages Philip Gladstone’s pskreporter.info data, delivered via an MQTT broker by Tom Fanning (M0LTE), to offer a responsive web application for visualizing propagation. The Map View presents a default visualization (grid AA00 / callsign MY8CALL) and distinguishes signal types: small spots for signals heard by a location, large spots for transmissions from a location, and teardrop markers for transmissions from the monitored callsign. Clicking a spot reveals detailed signal data in an overlay. The application includes a Log View for raw spot data and a Settings tab for customization. Users can filter tracking by specific Callsign or Grid, with preferences saved to the browser. A notable feature is the Time to Live (TTL) setting, adjustable from the default 60 seconds, which controls spot visibility duration to manage map clutter during high-traffic periods. The tool provides a clear, logic-driven interface for real-time signal monitoring.

Filter Free is the shareware version of Filter Solutions and Filter Light. Filter Free is limited to 3rd order or lower low and high pass filters, 2nd order or lower band pass and band stop filters, and 10 tap or lower FIR filters, and does not include most of the advanced design capabilities of Filter Solutions and Filter Light.

Inrad Roofing Filter installation instruction, The IC-775 Roofing Filter Mod consists of a 6 pole, 5 kHz wide filter followed by a high dynamic range, feedback amplifier.

This article describes an HF upconverter for the FunCube Dongle Pro. Designed for radio amateurs, the converter extends reception capabilities to lower frequencies (0 Hz to 30 MHz) by mixing them with a higher oscillator frequency (100 MHz). This translates the desired signal into a range detectable by the FunCube Dongle (64 to 1,700 MHz). Key components include a double-balanced mixer and a low-pass filter to suppress unwanted signals. The project provides schematics, filter specifications, and design considerations for construction.

Operating on the HF and VHF bands, the URE WebCluster serves as a real-time DX spotting network for amateur radio operators. It aggregates DX spots from various sources, presenting them with detailed information such as DX callsign, frequency, mode, and spotter details. The platform integrates essential propagation data, including current solar indices like _K-index_ and _A-index_, alongside visual propagation maps, which are crucial for planning long-distance contacts. Users can submit new DX spots, contributing to the collective intelligence of the amateur radio community, and filter existing spots by band, mode, or callsign, enhancing operational efficiency. This resource enables operators to monitor band openings and identify active DX stations, significantly aiding in _DXCC_ pursuit and contest operations. The integration of solar-terrestrial data directly within the cluster interface allows for immediate correlation between propagation conditions and observed DX activity, a feature not universally present in all web clusters. By providing both raw spot data and contextual propagation information, the URE WebCluster offers a practical tool for real-time decision-making during operating sessions, allowing hams to quickly adapt to changing band conditions and target specific _DX_ entities.

Adding 2 RCA inputs, 1 high impedance filtered audio output RCA 3, 3 HIGH PASS filters, 3 LOW PAS filters to the JRC NVA88 Speaker

Effective suppression of harmonics and parasitic radiation from HF transmitters is crucial, especially with the increasing sensitivity of VHF/UHF radio channels to interference. This project details a hybrid low-pass filter (LPF) designed to operate across the HF bands up to 51 MHz, making it suitable for 6-meter band operations while providing deep VHF/UHF suppression. The design addresses the challenge of modern interference landscapes, where even microvolt-level signals can disrupt wireless sensors and other simple VHF/UHF receivers. The filter utilizes a single elliptic link, combining high cutoff steepness with robust suppression in the hundreds of megahertz range. A key feature is the use of only two standard capacitor values, simplifying construction and component sourcing. The article provides a detailed schematic, performance characteristics, and _RFSim99_ model file, demonstrating a reflection coefficient S11 below 0.017 (VSWR < 1.03) across 1-51 MHz, ensuring minimal degradation to the antenna system. Construction notes include coil winding specifications and capacitor selection guidance, with recommendations for _FR-4_ assembly. Two capacitor sets are presented, with the first variant recommended for its lower RF current demands, keeping currents below 3 A at 1 kW passing power at 51 MHz. Fine-tuning involves adjusting frameless coils, with considerations for capacitor tolerance and high-frequency capacitance measurement accuracy.

The Wanted Alive (TWA) by OH2BUA is an online DX cluster service specifically tailored for digital mode enthusiasts, presenting real-time DX spots with a unique ranking system. Unlike traditional clusters, TWA sorts spots by decreasing DXCC most-wanted ranking, allowing operators to prioritize rare entities. It integrates data from various sources, including PSK Reporter and RBN, to provide a comprehensive view of current propagation conditions for modes like FT8, FT4, and JS8. This approach helps DXers quickly identify and pursue high-value contacts, optimizing their time on the air. OH2BUA's TWA provides a practical application for serious DXers by filtering the noise and highlighting the most sought-after DXCC entities. The service's focus on digital modes reflects the growing popularity of these efficient, low-power communication methods, offering a specialized tool that complements general-purpose DX clusters. By presenting propagation information through the lens of DXCC rarity, TWA assists operators in achieving DXCC awards and improving their overall DXing efficiency, particularly during contests or limited operating windows.

Direct conversion receivers (DCR) are gaining renewed interest due to advancements in semiconductor technologies and their suitability for integration in compact, low-cost, multi-standard applications. Unlike traditional superheterodyne receivers, DCR eliminates image frequencies and bulky off-chip filters but introduces challenges like DC offsets, nonlinearity, and noise issues. This tutorial explores DCR's historical development, compares it with other receiver architectures, and addresses its inherent obstacles. DCR's potential for integration and compatibility with software-defined radio highlights its role in modern communication systems despite its technical complexities.