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Some recent videos of the new Mid Class RTX by ICOM, the IC-7610 HF+50MHz amateur radio transceiver.

The San Bernardino Microwave Society, operating under the callsign _W6IFE_, serves as a significant technical hub for amateur radio operators specializing in frequencies above 1 GHz. This organization's influence extends across Southern California, providing a centralized resource for advanced RF experimentation and **regional frequency management** within the microwave spectrum. Its permanent value lies in its extensive archive of technical papers and project documentation, which are critical for operators engaged in high-frequency design and deployment. The society's infrastructure is primarily intellectual, focusing on the dissemination of specialized knowledge rather than a conventional repeater network. It offers a robust collection of technical papers from prominent members like K6PIP, K6BLG, and WA6EXV, covering topics such as Rubidium oscillator data, logging software, and filter design. This resource facilitates advanced amateur radio operations, including participation in microwave contests and the development of custom transverters for bands like 24 GHz. The site also details various member projects, such as the Owens Valley Radio Observatory Project, showcasing practical applications of **RF propagation analysis** and system integration. DXZone Focus: Microwave | Technical Papers | RF Propagation | Contest Results

This guide explores different radio bands that hobbyists use to talk to each other worldwide. It explains how these bands work and what they're used for. From low-frequency to high-frequency bands, each has its own unique features for people who enjoy communicating through radios

On December 12, 1901, Guglielmo Marconi successfully received the first transatlantic wireless communication, a Morse code "S" (three dots), at 04:30 GMT. This article details the setup for this groundbreaking experiment, noting Marconi's receiver in St. John’s, Newfoundland, Canada, utilized a _coherer_ and an antenna elevated by balloons and kites. The transmitting station at Poldhu, Cornwall, England, featured twenty-four 200-foot ships' masts and a 25-kilowatt alternator. The resource explains how this contact disproved contemporary beliefs about radio wave limitations due to Earth's curvature, later understood through _ionospheric propagation_. It frames Marconi's achievement as the "very first DX" in amateur radio terms, defining DX as telegraphic shorthand for distance and _DXing_ as the hobby of receiving distant signals. The article also provides external links for further reading on Marconi's experiments and the science behind transatlantic radio signal reception.

The official announcement of the Icom IC-7610 mid class amateur radio transceiver

This resource provides a historical analysis of amateur radio call sign assignment policies in the United States, detailing regulatory shifts from the Department of Commerce to the Federal Radio Commission (FRC) and subsequently the Federal Communications Commission (FCC). It documents the evolution of call sign issuance, from early reissuance practices in the 1920s to the implementation of the Group Call Sign Assignment System on March 24, 1978. This system categorized call signs (e.g., 1x2, 2x1, 1x3, 2x3 formats) into groups A, B, C, and D, correlating with license classes such as Extra, Advanced, General, and Novice, and specifying prefixes for contiguous U.S. and territorial areas (e.g., _AH_, _KP_, _KL_). The document further details the legislative process leading to the modern Vanity Call Sign program, initiated by a petition in June 1990 and formalized by the Omnibus Budget Reconciliation Act of August 10, 1993. It outlines the FCC's adoption of final rules on December 23, 1994, and the subsequent fee structure, with the first vanity call sign issued on May 31, 1996, at a cost of **$30.00** for a ten-year term. The ARRL's proposed "starting gates" implementation strategy is also described, which phased in eligibility for vanity call signs based on license class and prior holder status. DXZone Focus: Historical Document | Regulatory Analysis | Call Sign Formats | Fee Structure

Elecraft new QRP transceiver, an 80-10 m SSB/CW/Data station that fits in your pocket

VP8STI log on line VP8 DX Pedition

VP8STI and VP8SGI South Sandwich & South Georgia DX Pedition 2016 - VP8 Log Online, VP8 DX spots and VP8 related links

A simplified operating guide for the Yaesu FT-817

An article about the Beverage antennas, super long wire receiving antennas thar are unidirectional and have a very low noise that makes this antenna excellent for low band dxing. By Thomas R. Sundstrom W2XQ, 73, June 1981, 73 Magazine

_Amphenol RF_ manufactures RF connectors, RF adapters, RF attenuators, RF cable assemblies, and RF terminators. The company offers custom RF solutions, including modified connectors and integrated cable assemblies. Product examples include SMP to SMPM adapters, surface-mount SMB jack connectors, end-launch SMA bulkhead connectors, and non-magnetic SMPM connectors. The company's product portfolio also features single-crimp N-Type connectors, USCAR compliant Mini-FAKRA connectors, 2.4 mm to 2.4 mm adapters, and 2.92 mm plugs for 0.141-inch cable. _Amphenol RF_ produces MMCX and MCX cable assemblies on RG-316 and RG-174 cable, PFAS-free SMA connectors, and FAKRA rear mount bulkhead plugs for RG-58 and LMR-195 cable. Additional offerings include 2.92 mm to 2.92 mm adapters, BNC bulkhead jacks, SMA to MHF 4 LK cable assemblies, and 2.92 mm to SMA adapters. _Amphenol RF_ is headquartered in Danbury, Connecticut, and operates as part of _Amphenol Corporation_. The company maintains a global manufacturing and distribution network. DXZone Focus: RF connectors | Cable assemblies | Danbury, Connecticut | _Amphenol Corporation_

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

Early pictures and presetation of the Icom the IC-705, new all bands all modes QRP transceiver introduced at Tokio HamFair on August 31st September 1st 2019.

High Frequency (HF) radio propagation, particularly the phenomenon of "Skip," which enables long-distance radio contacts, is thoroughly explained for newcomers to the amateur radio hobby. The article begins by defining essential terms such as _radio signal_, atmosphere, troposphere, stratosphere, mesosphere, thermosphere, exosphere, and aurora, setting a foundational understanding for subsequent discussions. A significant portion of the content focuses on the ionosphere, identifying it as the primary driver of HF propagation. Its structure, including the D, E (E1, E2, E3), and F (F1, F2) layers, is detailed, along with how solar radiation influences these layers to refract radio waves back to Earth. The concept of "The band is opened!" is introduced, specifically noting refraction around **21 MHz**. The guide also touches upon ground waves, space waves, and temperature inversions affecting VHF/UHF propagation, contrasting them with the dynamic nature of ionospheric HF propagation. Factors like antenna polarization, takeoff angle, and the sun's solar cycle are mentioned as critical influences on signal path, with examples like 80-meter band propagation after sunset and 40-meter/20-meter bands offering near-constant propagation.

The DIY Power Meter project utilizes the _INA226_ high-side power monitoring chip, paired with an ATtiny85 microcontroller, to measure voltage, current, and power, displaying the results on a 128x32 OLED screen. The INA226 communicates via an I2C interface and is programmed with a calibration factor based on the shunt resistance and current register LSB. The project is designed to handle a maximum current of 500mA using a 0.16ohm shunt resistor, which can be adjusted to a 0.2ohm resistor, reducing the full-scale current range to 409mA with a resolution of **12.5uA**. The shunt resistor dissipates only 33mW at maximum current, making 1/4 watt resistors suitable for the setup. The PowerMeter.ino sketch configures the shunt resistance and maximum design current, automatically calculating the calibration factor. The project can be prototyped on a breadboard using an Arduino Uno, employing the Wire library for INA226 and OLED communication, and the u8g2lib library for the OLED display. For the ATtiny85 version, the Adafruit-TinyWireM and Tiny4kOLED libraries are used. The power meter is independently powered by a 3V CR2032 cell, with power switching options including manual switches or DC switched jacks. The low-side n-channel MOSFET switch configuration is tested but introduces voltage drop issues, making manual switching a more reliable option until a suitable DC switched jack is found. DXZone Technical Profile: INA226 | ATtiny85 | OLED Display | Power Meter

Let this microprocessor controlled MFJ Contest Voice KeyerTM call CQ, send your call and do contest exchanges for you in your own natural voice

This **PDF report** documents a _maritime mobile_ DXpedition operating from the _Southern Ocean_ near Antarctica, detailing antenna deployment strategies on a sailing vessel. It addresses power management systems for remote operations and propagation characteristics specific to polar regions on **20m and 40m** bands. Operational strategies include managing high-density pileups using split frequency operation and maintaining signal integrity during periods of high aurora activity. Equipment considerations cover specific transceiver models like the Icom IC-7300, antenna types optimized for marine vessel installation, and battery power systems for extended periods without shore power. The resource also examines the use of satellite communication for real-time log uploads and QSL confirmation from remote locations, and discusses mitigating signal degradation from ice accumulation on antennas. DXZone Focus: PDF report | Maritime Mobile DXpedition | Polar Propagation | Split Frequency Operation

The International DX Amateur Radio Club provides a structured environment for amateur radio operators interested in long-distance communication. The club offers a variety of awards, including the DX Countries Award, DX United States Award, and DX Continents Award, among others. These awards recognize achievements in contacting stations across different geographical areas, such as Europe, Africa, South America, and Asia. The club also supplies resources like DX Spots, Grey Line Map, and Solar Data to assist operators in optimizing their communication strategies. The DX Code of Conduct emphasizes disciplined operating practices. Operators are encouraged to listen carefully before transmitting and ensure they have correctly identified the DX station's call sign. The guidelines advise against interfering with ongoing communications and stress the importance of patience, such as waiting for the DX station to complete a contact before calling. Operators are reminded to send their full call sign and avoid continuous calling, maintaining respect for fellow operators to foster a cooperative amateur radio community. DXZone Technical Profile: DX Awards | DX Code of Conduct | Grey Line Map

Yaesu FT-818ND HF VHF UHF All mode portable transceiver. Announced in 2018, production of this QRP all mode portable transceiver has been discontinued some years later.

Our Article about the ICOM IC-7760 announce done by ICOM at the annual Ham Fair in Tokyo

The _Colorado QSO Party_ is scheduled for **September 12, 2026**. This amateur radio event focuses on contacts with stations operating within Colorado. The _Grand Mesa Contesters of Colorado_ sponsors the event. Operators may pursue contacts across all **64 counties** of Colorado. Activations for programs such as POTA and SOTA are permissible during the event period. Logs generated from these activations are eligible for submission to both the _Colorado QSO Party_ and the associated operating program. DXZone Focus: QSO Party | Colorado | Mixed | All Amateur Bands

This online project documentation details the construction of a hands-free microphone interface unit designed for _mobile_ amateur radio operation. The curriculum covers the integration of electret microphone elements with amateur radio transceivers, specifically addressing **VHF** band communication. It outlines the circuitry for a switch box that provides an interface between various radio models and microphone types. The guide specifies the inclusion of a **1750 Hz** tone-burst generator for accessing amateur radio repeaters, an operational protocol for many VHF systems. Design considerations include the reduction of ambient vehicle noise through an adjustable audio input level control. The project provides schematics and wiring diagrams for connecting the interface unit to specific amateur radio transceivers, including the Yaesu FT-817. It addresses the selection and adaptation of readily available electret microphone and earpiece assemblies, initially sourced from mobile phone accessories, and later from dedicated headset units. The design incorporates a control mechanism for radio functions, enabling hands-free operation during _mobile_ excursions. Circuit details cover power supply considerations for the electret microphone and signal routing for both transmit audio and received audio monitoring. The documentation specifies component selection for the switch box, ensuring compatibility with common amateur radio microphone input impedances and output levels. This includes considerations for PTT line switching and audio path isolation. DXZone Focus: Online Project Documentation | Hands-Free Mobile Microphone Interface | Electret Microphone Integration | 1750 Hz Tone-Burst Generation

This online construction guide details the assembly of a signal generator specifically for the **13cm band** (2.4 GHz). The curriculum focuses on the integration of a Voltage Controlled Oscillator (VCO), specifically the ROS-2400, to produce a stable RF signal. The resource outlines the necessary components for frequency generation and output, including the use of a Mini-Circuits MMIC amplifier for signal conditioning. The construction protocol involves configuring the ROS-2400 VCO to operate within the 2.3 GHz to 2.45 GHz range, ensuring frequency coverage for amateur radio _microwave experimentation_. The guide specifies the output power level, approximately 70mW, directly from the MMIC stage, indicating its application as a low-power instrumentation source rather than a transmit-capable device. This project provides a practical example of constructing a dedicated test instrument for microwave frequency measurements and system alignment on the **13cm band**. DXZone Focus: Construction Guide | 13cm Signal Generator | VCO Integration | Microwave Experimentation