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This project revisits a minimalist software-defined radio (SDR) receiver built using a Raspberry Pi Pico, now optimized for simplicity and affordability. Designed for breadboard assembly with through-hole components, the receiver covers 0–30MHz, supporting CW, SSB, AM, and FM modes with an OLED display and spectrum scope. Key improvements include enhanced frequency accuracy, reduced op-amp saturation, and lower-cost components. Powered by three AAA batteries, it delivers standalone operation for global signal reception. Ideal for hobbyists, the design fosters experimentation and is documented with firmware and schematics available online.

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.

The QMX+ Transceiver Kit from QRP Labs is a high-performance, feature-packed 160-6m 5W transceiver designed for hams. This multi-mode kit includes embedded SDR, USB sound card, CAT control, synthesized VFO, RTC, and optional internal GPS. It can be used in CW, digital, and SSB modes, with standalone CW operation, digi mode via USB to PC, or SSB operation. The kit offers standalone beacon functionality and shares firmware with the QMX model. With an optional enclosure, battery-backed RTC, and GPS, the QMX+ is versatile and easy to build, making it ideal for ham radio operators looking for a customizable transceiver kit.

Documents the A35EU DXpedition to Tonga, specifically targeting the _IOTA OC-049_ Tongatapu group during 2018. The resource outlines the operational bands from 10 to 160 meters and the primary modes utilized, including _CW_, _SSB_, RTTY, and FT8. It provides essential information for DXers interested in confirming contacts with this rare entity, detailing the logistical aspects of the operation and the specific island group activated. This page serves as an archive for the A35EU operation, offering QSL update information and confirming that all log queries were processed and a fresh log uploaded to _Clublog_. Such details are crucial for operators seeking to verify their contacts and apply for awards like DXCC or IOTA, providing a definitive record of the expedition's activity and post-operation administrative status.

VARA HF is a soundcard modem that can be found on the HF bands exchanging traffic (Winlink). VARA implements an High Speed Data Mode and comes in 2 separate programs VARA FM and VARA HF. VARA is a High Performance HF modem based on OFDM modulation. VARA Modem, brings state of the art Military grade technology to new and existing HF data. Introduces a new standard of technology available for Amateur and Commercial use. Designed for operation within a SSB Bandwidth of 2400 Hz.

The E6AF DXpedition to Niue (OC-040) in 2019 successfully activated a rare DXCC entity, providing thousands of contacts for the global amateur radio community. Operations focused on maximizing QSOs across various **HF bands** and modes, significantly contributing to the DXCC program. The team, led by SP9FIH, meticulously planned antenna deployments and station setups, including a specific focus on **Fox-Hound mode** for digital operations, to ensure robust signal paths and efficient pile-up management. Operational details included specific schedules for CW, SSB, and digital modes, aiming to accommodate different time zones and propagation windows. QSL information and log search functionalities were made available post-operation, facilitating confirmation for thousands of contacts. The expedition encountered logistical challenges, including power supply failure and strict COVID-19 travel restrictions that delayed licensing. Despite these hurdles, the E6AF and E6CI stations provided valuable contacts from Niue, a sought-after location for many DXers.

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.

DX Pedition to Galapagos will be active from October 26th to November 7th, from 6 to 160 meters (including Warc bands) on CW, SSB and Digi modes with at least 4 stations on the air at the same time.

The ICOM IC-705 remains a standout portable transceiver after 3.5 years of use. Its unmatched feature set includes multi-band/mode support, built-in WiFi, GPS, remote operation, and excellent third-party app integration, making it versatile and user-friendly. Despite competition like the Elecraft KX3 and Yaesu FT818, the IC-705 excels in flexibility, durability, and ease of use. Whether for QRP operations, digital modes, or SSB, it delivers exceptional performance in diverse settings, reaffirming its status as the best portable transceiver on the market.

The Ukrainian Contest Club (UCC) website details contest activities, including a March 2026 contest calendar compiled by _UW3WF_ that excludes specific "exotic" tests, mini-tests, sprints, VHF competitions, and events organized by Russian entities. It lists major contests such as the ARRL International DX Contest, Stew Perry Topband Contest, and CQ WPX SSB Contest, providing dates, times, modes, bands (e.g., **10-160m**), organizers, log submission methods, and deadlines. The resource also highlights Ukrainian participation in various international contests, noting specific callsigns that represented the UCC, and acknowledges new Ukrainian records, such as UW5Y's new record in the ARRL DX CW Contest. The site presents contest results and rankings, including the top 20 Ukrainian contesters in the World Amateur Radio Contesting Association (WARCA) rating for 2019-2024, with _UW1M_ ranked #18 globally and #1 in Ukraine with **26,490.32** points. It also details the club's 12th place finish among 155 clubs worldwide in the CQ WPX Contest 2024 (CW + SSB). The resource includes information on WRTC 2026 participants from the club and lists members excluded due to collaboration with adversarial entities, reflecting the current geopolitical context.

From March 2 to March 11, 2018, a Norwegian team operated as Z2LA from Zimbabwe, focusing on 160m through 10m bands using SSB and CW modes. The operation, described as "holiday style," aimed to provide contacts for DXers worldwide seeking a rare DXCC entity. Key equipment included a SUNSDR PRO II, an Elecraft KX3, and an Icom 706 MK2G as a spare radio, supported by two Juma 1000 amplifiers for robust signal output across the bands. Antenna systems were tailored for multi-band operation, featuring an Inv L for 160m and 80m, sloping dipoles for 30m/40m, and a _Hexbeam_ from SP7IDX Technology covering 20m to 10m. For improved reception, the team deployed a SAL 30, two reversible BEV antennas from remoteqth.com, and a BOG from K1FZ, enhancing their ability to hear weak signals. QSL information directs operators to Clublog for log search and M0OXO Charles for OQRS, explicitly requesting no bureau cards. The team comprised LA7THA Rune, LA7WCA Arne, and LA9VPA Thor, successfully making numerous contacts and contributing to the DX community's pursuit of _Zimbabwe_ as a DXCC entity.

Many low-power SSB rigs and kits lack dedicated speech processor circuitry, although most modern HF rigs include it. Speech processing is crucial for low-power SSB to overcome QRM. This simple, low-cost circuit integrates a microphone element and can be housed in a defunct desk mike. It features a feedback amplifier, audio preamplifier, and adjustable speech compression control

The Homebrew uSDX SDR TRX is an experimental transceiver primarily designed for CW and Digital modes due to limitations in meeting FCC requirements for SSB. Developed from the QRP Labs QCX, it incorporates advanced SDR features while utilizing an 8-bit ATMEGA328P. The µSDX community fosters open-source development with various design streams and versions, encouraging collaboration and sharing among enthusiasts.

Single-sideband (SSB) radio enhances spectral efficiency but poses challenges with audio intelligibility, particularly in noisy conditions. A microphone audio compressor addresses these issues by dynamically managing the audio signal’s dynamic range. It amplifies quiet sounds and attenuates loud ones, ensuring consistent audio levels for improved clarity. Benefits include increased intelligibility, higher average power, and reduced spurious emissions. While essential for optimal SSB performance, careful parameter adjustment is crucial to balance natural sound quality and effective communication across various operating modes.

The Pikes Peak Radio Amateur Association (PPRAA) serves as an ARRL Special Service Club, providing a calendar of events and activities for its members and the wider amateur radio community. The resource details upcoming events such as the USS Pueblo Memorial Museum Ships Weekend activations, a Cubical Quad Antenna Workshop, LARCFest, and various hamfests including Dayton Hamvention and Duke City Hamfest. It also lists on-air activities like a FreeDV digital voice mode event on 10 meters, a Black Friday Simplex Event on 2M and 70cm, and a 10m event for Technician class operators, emphasizing SSB privileges from 28.300 to 28.500 MHz. The PPRAA's event schedule includes educational opportunities like a Technician Class and a Soldering Workshop, alongside social gatherings such as the PPRAA Picnic and Car Show. Past event summaries highlight successful activities like the 2024 Megafest Raffle, Winter Field Day, and multiple fox hunts utilizing frequencies like 147.420, 147.480, and 147.540 MHz. The club actively supports POTA activations, exemplified by their AF0S park activation at Cheyenne Mountain State Park, and participates in historical commemorations like the USS Pueblo Memorial operations, demonstrating a broad engagement across various amateur radio facets.

The UV-K5 HF Fullband receive firmware version 0.3 introduces enhanced SSB capabilities using the SI4732-A10 chip. Released separately from UV-K5 CEC firmware, it offers improved HF reception, mode changes, frequency fine-tuning, and user modifications. New PCB designs and detailed usage instructions are included.

When new to the 2-meter FM transceiver, securing a quiet frequency for chatter seems straightforward, but it's essential to navigate FCC rules and band plans effectively. Even though frequency allocations are consistent above 50 MHz for Technician licenses, adherence to specific segments within the 2m band—ranging from 144 MHz to 148 MHz—is crucial. This includes respecting designations for different modes like CW, SSB, and FM to prevent interference, particularly with satellites and exotic modes like EME. Understanding and following the structured band plans not only ensures legal compliance but also optimizes frequency use and minimizes disruptions in the amateur radio community.

John Lemay’s (G4ZTR) review of the Yaesu FT-847 offers a practical look at this all-mode transceiver, spanning 160m to 70cm, including 4m. While it falls short in dynamic range and sensitivity, its "shack-in-a-box" design shines for VHF DXing and multi-band use. Lemay shares hands-on tweaks, like calibrating 70cm with beacons and integrating footswitches for SSB and CW. The TX Inhibit feature simplifies sequencing with external gear. Despite minor flaws, the FT-847’s versatility and mod-friendly nature make it a solid pick for amateur radio enthusiasts craving flexibility.

Single Sideband (SSB) operation requires careful attention to the relationship between a radio's displayed frequency (suppressed carrier) and the actual 3 kHz wide audio signal. This resource clarifies how Upper Sideband (USB) and Lower Sideband (LSB) signals occupy spectrum above or below the indicated frequency, respectively. It provides practical examples for General Class operators on the **20m** and **40m** bands, such as setting a VFO to 14.226 MHz for USB on 20m or 7.178 MHz for LSB on 40m, to maintain a safe margin from band edges. The resource emphasizes the critical importance of staying within allocated band limits to prevent out-of-band emissions, particularly when operating close to band edges. It includes relevant excerpts from **FCC Regulation Part 97**, specifically section 97.307, which details emission standards, necessary bandwidth, and spurious emission attenuation requirements. The text explains that unused sidebands are considered spurious emissions and notes that modern HF equipment typically exceeds the 43 dB spurious emission reduction standard, often achieving 60 dB or more.

This paper presents an 80 meter wire 3-element beam antenna in an inverted-V configuration, designed for limited-height towers. Using EZNEC modeling, the antenna features a central parasitic reflector and two switchable driven elements at each end, enabling NE/SW coverage without moving parts or networks. Element lengths are optimized for SSB (3.8 MHz) and CW (3.5 MHz) operation, with a 50 Ω feed and rope-supported boom. The design delivers high gain, effective takeoff angles, and excellent reception, confirmed in real-world DX contest operation. Its simplicity, reliability, and ease of construction make it ideal for operators seeking performance without complex matching systems.

YaesuFT1000MK V stands out with improved close-spaced SSB transmit performance, reversing a trend seen in other modern radios. Featuring a class-A mode, it offers clean HV finals when kept out of ALC. However, two significant flaws persist: the noise blanker causes receiver IM distortion, and the transmitter lacks wave-shaping on CW, resulting in pronounced keyclicks. Preliminary tests reveal strong keyclicks +1kHz and -1kHz, prompting a combined modification to address both issues.

The TY0RU DXpedition to Benin in 2022 achieved over **100,000 QSOs** from Cotonou, IOTA AF-051, operating across 160m through 6m bands using CW, SSB, and FT8 modes. The operation involved a team of 12 operators, including _F5RAV_, _F4WBN_, and _F1TCV_, utilizing multiple stations with transceivers like the Icom IC-7300 and IC-7610, paired with amplifiers and various antennas such as verticals, dipoles, and a 4-square array for 40m. The expedition's log is available on Club Log, supporting OQRS for both direct and bureau QSLs, with F5RAV serving as the QSL manager. The site details the team's travel, setup, and operational challenges, including local conditions and equipment deployment, offering insights into the logistical complexities of activating a rare DXCC entity. Donors are acknowledged, and a photo gallery documents the activity.

Assessing the ICOM IC-R9000 communications receiver, this review details its operational parameters and user experience for radio enthusiasts. Introduced in 1985, the IC-R9000 covers a broad frequency spectrum from 0.1 MHz to 1999.8 MHz, making it suitable for a wide array of listening activities from medium wave (MW) to VHF/UHF. Key performance metrics include a dynamic range of **102 dB** with the narrow SSB filter, crucial for discerning weak signals in crowded bands, and its substantial physical dimensions of 424 x 150 x 365 mm and 20 kg weight. The receiver's architecture supports various modes, though it notably lacks synchronous detection, a feature often desired for improved AM reception under fading conditions. It incorporates 1000 memory channels and robust scanning capabilities, facilitating efficient monitoring across its extensive frequency range. This analysis provides insights into the IC-R9000's capabilities and limitations, offering a historical perspective on a significant piece of amateur radio and shortwave listening hardware.

IOTA: OC-003 activation planned for November 01 – November 15, 2024 Operation modes: SSB, CW, RTTY , FT8, FT4, PSK Bands: 160 – 6m, QO-100

The HD8G DXpedition will take place in the stunning Galapagos Islands from April 18 to April 26, 2025. This operation will involve 26 dedicated amateur radio operators activating the islands, which are designated as IOTA SA-004. The team aims to make a significant number of contacts, providing an exciting opportunity for DXers and enthusiasts to work this unique location. With a rich history and diverse wildlife, the Galapagos Islands offer a picturesque backdrop for this event. Participants can expect to engage in various modes of operation, including SSB and CW, as the team works to log as many QSOs as possible. The DXpedition is anticipated to generate a high volume of activity, with operators from multiple countries contributing to the effort. This is a prime opportunity for those looking to add a rare entity to their DXCC list or simply enjoy the thrill of working a special event from a remote location.

Presents detailed expedition charts and statistics for the **XX9W** DXpedition, covering operating time, total QSOs, unique calls, and duplicate QSOs. The resource provides comprehensive band and mode breakdowns, including FT8, SSB, CW, and FM, across 80m, 40m, 30m, 20m, 17m, 15m, 12m, 10m, 6m, 2m, and 70cm. Users can access DXCC statistics by band and mode, daily QSO totals, and multiband QSO statistics. Continent-by-mode and continent-by-band breakdowns are also available, detailing activity from Africa, Asia, Europe, North America, Oceania, and South America. The platform also tracks the expedition's impact on user totals, showing new band, new mode, new band + new mode, new slot, and new DXCC contacts.

This resource details **cooling modifications** for Ameritron AL82, AL1200, and AL1500 HF amplifiers, specifically addressing heat issues encountered during high-duty-cycle digital mode operation. The author, WD4NGB, observed excessive heat in the tank area and band switch on an AL82, attributing it to insufficient exhaust over the 3-500 tubes and a complete lack of exhaust over the tank area. The modifications aim to prevent common failures such as damaged band switches and deformed insulating materials by increasing airflow and exhaust area. The page describes adding five holes to the chassis for enhanced cooling to the band switch and tank area, alongside enlarging the exhaust area over the inner 3-500 tube and the tank area on the amplifier cover, utilizing expanded metal for safety and RF shielding. The original cover featured 26.25 square inches of exhaust; the modified version significantly increases this to 48.5 square inches over the tubes and introduces an additional 15 square inches over the band switch. These changes are intended to resolve heating problems encountered during heavy, 100% duty cycle use in modes like RTTY or long SSB contests, which typically generate substantial heat. The article also discusses upgrading to a higher output fan, such as the G2E085-AA05-21, and modifying tube sockets for improved airflow and reduced back pressure, citing Tom Rauch (W8JI) of CTR Engineering as a source for parts.

Presents the S21WD DXpedition to Bangladesh (IOTA **AS-140**) scheduled for 2026, organized by the Next Generation DX Club e.V. It outlines the project's progress, including final hardware and systems testing, and the team's successful arrival and activation from the target location. The resource provides a concise summary of Bangladesh, covering its geography, cultural aspects, and economic landscape. The page includes the Clublog Most Wanted ranking for Bangladesh, categorized by continent and mode, as of January 2026. The DXpedition aims to achieve over 70,000 QSOs across CW, SSB, RTTY, and FT8 modes, with a specific focus on RTTY (targeting over 2,000 QSOs) and **lowband** operations. The team plans a Multi-Single entry in the ARRL CW 2026 contest. QSO data will be uploaded to Clublog and LoTW, with Clublog livestream and daily free LoTW uploads anticipated, contingent on stable internet connectivity. The S21WD callsign corresponds to CQ Zone 22 and ITU Zone 41. Further details include a preliminary bandplan, FT8 operating guidelines using MSHV software, a VOACAP DX Prediction link, and an azimuthal map centered on Bangladesh. QSL services are managed by DJ4MX via Clublog OQRS, offering direct, bureau, and LoTW options, with daily LoTW uploads expected.

Examines the Sangean ATS-505 portable receiver, a unit introduced in March 2000, providing an in-depth analysis of its capabilities. The review details critical specifications such as its 6 Volt DC power requirement, utilizing 4 AA batteries, and its physical dimensions of 128 x 214 x 39 mm, weighing 840 g without power cells. Frequency coverage spans **LW** from 153-279 kHz, **MW** from 520-1710 kHz, **SW** from 1711-29999 kHz, and FM from 87.5-108 MHz, making it a versatile listener for various broadcast types. Key features highlighted include a backlit display for low-light operation, 45 memory presets for quick access to favorite stations, and the inclusion of Single Sideband (SSB) mode, which is crucial for serious shortwave listening and utility monitoring. The review also draws technical comparisons with other Sangean models, specifically the ATS-404 and ATS-909, pointing out differences in band coverage and operational features. This independent assessment offers practical insights into the ATS-505's performance, helping enthusiasts understand its place within the portable receiver market.

TX5EU 2026 DXpedition to Raivavae Island, **OC-114**, within the Austral Islands, providing a detailed account of the German/Dutch team's operations. The resource outlines the participation of operators such as DL2AWG Guenter, PA2KW Evert, and DK2AMM Ernoe, who engaged in CW, SSB, RTTY, and various digital modes. It documents the real-world challenges encountered, including significant equipment failures and antenna damage to 80/60m, 30m, and 10m verticals due to adverse storm conditions. The page offers timely news updates on the expedition's progress, noting repairs to a power amplifier's 10/12m bandpass filter, which enabled three stations to utilize amplification. Earlier reports highlighted power failures and the loss of multiple power amplifiers, necessitating one station to operate barefoot FT-8 with 100W. The team's persistent efforts to repair antennas as weather permits are also detailed, reflecting the dynamic nature of remote island operations.

Over 44,000 square kilometers of Scotland's natural beauty provide a unique backdrop for the _GMFF_ award program. Designed for amateur radio operators who thrive on portable operations, this program encourages activators to set up stations in designated flora and fauna areas. Participants engage in _SSB_ and _CW_ modes, making contacts from these scenic locations, which are part of the _WorldWide Flora and Fauna_ network. Activators and chasers alike benefit from the program's structure, which awards points for successful contacts. The _GMFF_ program is part of a larger global initiative, allowing operators to contribute to conservation awareness while enjoying their hobby. With a focus on environmental preservation, the program aligns amateur radio activities with ecological interests, promoting responsible and sustainable operating practices. The program's website provides resources for participants, including maps of designated areas and guidelines for operation. By participating, operators not only enjoy the challenge of portable operation but also support the conservation of natural habitats. The _GMFF_ program thus combines the thrill of amateur radio with a commitment to environmental stewardship.