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Transmitting operations in the 50-54 MHz range offer some unique problems that over the past 50 years have stymied station owners, forcing them to tolerate quiet hours and hostility from family and neighbors attempting to enjoy other electronic services.

Coaxial cable stripping for PL-259 connectors requires precise measurements to ensure optimal RF performance and mechanical integrity. For RG-8X, the outer jacket is stripped 1/2 inch, the braid 5/16 inch, and the dielectric 1/8 inch, leaving the center conductor exposed. RG-58 preparation involves a 1/2 inch jacket strip, 1/4 inch braid strip, and 1/8 inch dielectric strip. These specific dimensions facilitate proper soldering and crimping, minimizing impedance discontinuities at the connector interface. Different coaxial cable types, such as RG-8 and RG-213, necessitate varied stripping lengths due to their construction. The _PL-259_ connector, a common UHF type, relies on these exact preparations for a secure fit and low-loss connection. Incorrect stripping can lead to high SWR, RF leakage, and mechanical failure, impacting overall station efficiency. The guide details these critical dimensions for several popular coax cables. Using a dedicated _coax stripper_ tool or precise measurements with a utility knife improves consistency.

A 0-30 MHz step attenuator, constructed from switchable Pi attenuation pads, provides a practical tool for evaluating receiver sensitivity and calibrating S-meters. The design utilizes readily available 5% tolerance resistors, with values derived from paralleled components to achieve specific attenuation steps. A schematic (Fig 1) illustrates the circuit, including PCB pad shielding, while a table details required and actual resistor values, along with percentage differences. Measurements of voltage input versus output at various frequencies are used to calculate dB attenuation, presented in a graph (Fig 4). The resource includes formulas for determining output voltage from a known input and a comprehensive 0-40 dB voltage multiplier table, which is crucial for precise signal level management. The project also references external attenuator calculators and equations for further study. Photos (1-3) provide visual guidance for the assembled unit, showing bottom, top, and front views. The project emphasizes the use of **Pi attenuation pads** and **receiver sensitivity** evaluation, offering a hands-on approach to RF signal management.

Article on radio frequency interferences, with a long list of common RFI cause, like Plasma TV, Solar panels inverters, fluorescent tube lamps.

FCC Policy on Human Exposure to Radiofrequency Electromagnetic Fields

FHD22 radio-relay transmitter and receiver by F4DAY

TX3A Official web site of Chesterfield Islands dx pediition from Nov 23 to Dec 6, 2009.

Direct experience of portable operations of the FT-817 transceiver by Yaesu and the small power amplifier by RM Italy with 300W output

Article descrive the different types including coax and open-wire feeder and waveguide.

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

Preprinted from the 1997 ARRL Handbook for Radio Amateurs. Thermal Effects of RF Energy, Safe Exposure Levels, Cardiac Pacemakers and RF Safety, Determining RF Power Density

RF is causing strange issues on the touch sensor buttons, controlling inputs, volume, channels on Samsung LCD TV. Solution is to disable front touch panel.

Ham radio transmissions can interfere with television reception. This is called television interference, or ham radio TVI. Consumer adoption of cable television has significantly reduced ham radio TVI. But the introduction of IPTV, or television over phone systems, has brought ham radio TVI back, often with a vengeance. Here's why

My Amateur Radio Webpages and Help with QSL Basics

If you thought you knew everything about balun performance characteristics, there is an important figure of merit you may have neglected

Demonstrates MegaPhase's extensive product line of RF and microwave coaxial cable assemblies and components, engineered for demanding applications up to 110 GHz. Key offerings include _Test & Measurement Cables_ with superior phase and amplitude stability, _RF & Microwave Cables_ utilizing _GrooveTube®_ technology for high power systems, and a range of RF components like directional couplers and power dividers. The site details specific cable types such as _Alumibend™_ for space-qualified, ultra-light applications through 90 GHz, and armored cables designed for rigorous environments up to 50 GHz, emphasizing their robust mechanical strength and measurement repeatability. The resource highlights applications across diverse sectors, including space programs like the _Hayabusa_ mission, global security (C5ISR), military airborne systems (MIL-T-81490), telecom, and automated testing. It also provides technical insights through "How To" guides on measuring amplitude/phase stability vs. flexure and proper connector cleaning. The company's commitment to quality is underscored by its rigorous testing protocols and a strong warranty, ensuring reliable operation in critical systems.

Considerations and benefits of using solar power for amateur radio by CT Solar

Statio evaluation guidelines and rules for correct antenna setup

an overview, introduction or tutorial about the basics of electronics filters including the types of filter and the various filter design considerations and parameters

Interface board was for connecting Yaesu FT-817ND transceiver to Android phone or tablet. The board was developed for experimenting with RTTY, SSTV and other digital modes using DroidRTTY, DroidSSTV and other software on an Android phone.

KC901S Handheld vector antenna analyzer RF ANALYZER 3GHz S11 S21 Fieldmeter RF Source Spectrum

The Norfolk Repeater Group

DataBridge wireless RF modem modules facilitate point-to-point data transmission, supporting analog, digital, and serial RS232 UART signals. These modules are engineered for robust wireless communication, offering a reliable solution for various industrial and amateur radio applications requiring secure data links. The product line includes specific models designed for different frequency ranges and power outputs, ensuring compatibility with diverse operational requirements. Each module integrates advanced RF technology to maintain signal integrity over distance, crucial for remote monitoring and control systems. The design emphasizes ease of integration, allowing users to quickly deploy wireless data links without extensive configuration. Key features encompass low power consumption and a compact form factor, making them suitable for embedded systems and portable devices.

Xggcomms specialise in producing cost effective, high quality CAT and Audio interfaces for Icom and Yaesu Amateur Radio Equipment. Our interfaces are fully compatible with a large range of CAT and Digital Mode control software.

A multi tool Windows program that has been designed to offer the EMC RF and Radio Engineer a large variety of tools for Attenuation calculation, VSWR analysis, FIR Filter calculations, EMC system configuration, Radar testing , RF Filter calculation and much more without the need of a live internet connection.

Complete microphone wiring handbook for most popular radio transceivers provided by Astatic Microphones.

Deutscher Amateur Radio Club - Ortsverband Dusseldorf, R01

Internal Bluetooth interface for miniVNA, Bluetooth connection to the PC allow Full cordless operation with ao external components

Mirage BD-35 2M/70CM RF amp high SWR, how to troubleshoot

Bird Technologies, The RF Experts - manufacturer of Analyzers, Attenuators, Terminations & Loads, Duplexer and Triplexers and RF Wattmeters

Mitigating impulse-type noise, a common challenge in the **HF radio spectrum**, often requires specialized processing before the signal reaches the transceiver's receiver stages. The NR-1 addresses this by functioning as an RF interference removal device, specifically a noise blanker, targeting transient noise sources. Its operational range extends from 1.6 MHz to beyond 70 MHz, making it suitable for various amateur radio bands and general shortwave listening applications. Unlike QRM eliminators or X-phasers, the NR-1 does not require a separate noise antenna for its operation, simplifying its integration into existing station setups. The device's design focuses on wideband performance, allowing its use both within and outside the allocated amateur radio frequencies. Documentation detailing its operation is available, providing insights into its technical specifications and deployment. This unit is a hardware product, conceptualized and implemented by SV3ORA.

RF Saferty articles publishes by ARRL

Network Analyzer on an Arduino Shield which covers from 0-72MHz using an Analog Devices AD9851 DDS chip

This is a Solid State Amplifier Project. It uses 4 MRF150 MosFet Power Transistors. The Power Supply Voltage is 50 VDC at 21.5 Amp. The max power available is 1,075 Watts. The Efficiency is about 65% +/- and runs Class AB Solid State.

Offers a range of high-performance RF interconnect solutions, addressing the critical need for reliable signal integrity across diverse radio frequency applications. Their product line includes custom cable assemblies, various **RF connectors** (such as SMA), adapters, and terminators, designed to meet stringent specifications from DC up to 40 GHz. These components are essential for maintaining low insertion loss and excellent VSWR in demanding environments, from test benches to operational communication systems. The company specializes in providing tailored solutions for both commercial and government sectors, emphasizing precision manufacturing in Warner Robins, Georgia. Their offerings are crucial for engineers and operators requiring specific lengths, connector types, and performance characteristics for their radio equipment and test setups. Ensuring robust connections and protection against transient voltage events, their **surge protectors** are integrated into systems to safeguard sensitive electronics from damage, a common concern in outdoor or high-power installations.

This PDF document outlines the process for establishing an **OpenWebRX+** station utilizing Software Defined Radio (SDR) devices on a Linux platform, specifically Debian Bookworm. It details the capabilities of such a setup, including reception across various frequency bands supported by the SDR hardware and the decoding of multiple modes like FM, WideFM, SSB, AM, ADSB, FT8, and CW, with examples provided for FT8 reception and mapping, sensor data, and ADSB. The guide recommends specific hardware configurations, suggesting older x86-64 laptops with 4GB RAM or Raspberry Pi 4 models for the host system. For SDR devices, it endorses **RTL-SDRv3/v4** or HackRF, noting the necessary driver installations for RTL-SDR. The software installation sequence is meticulously laid out, from installing Debian Bookworm to adding OpenWebRX+ repositories, installing the application, and configuring device-specific drivers. Authored by Christian Horn (JL1AYH), the resource also includes a brief personal background of the author. It concludes with instructions for accessing the OpenWebRX+ interface via a web browser, either locally or remotely over a network, and provides contact information for further inquiries.

The FCC has answered some of ARRL questions about the RF-exposure rules. Changes to the regulations have a few pleasant surprises for Amateur Radio.

A deep analysis of UHF connectors performance tests, including return Loss of UHF Connectors, Mismatch Loss of UHF Connectors, SWR of UHF Connectors

Two beacons in 3 and 1.2 cm band, 10368.755 MHz and 24048.870 MHz

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.

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.

Amateur radio club from Germany

Equipment and Components for the RF and Microwave industry. AtlanTecRF is a global supplier of microwave and RF components and equipment to the aerospace, defence, telecommunications and scientific markets.

28 Dec 05 - 4 Jan 06 Grand Cayman IOTA: NA 016 GL: EK99, Jamaica IOTA: NA097 GL: FK17

DMR personal web site. Includes download links for Codeplug for Hytera AR685 PD685G, PD785G, PD785 & X1P with DMR Plus and Brandmeister support with VFO like channels. Repeater maps. In German.

ARRL FCC RF Exposure Regulations

Elmendorf Amateur Radio Society Joint Base Elmendorf-Richardson JBER, Alaska

Ham Radio personal web site

Voldatech, a manufacturer based in China, produces a range of RF feeder cables and site components essential for amateur radio installations and telecommunication infrastructure. Their product line includes various types of coaxial cables, such as **50 Ohm** and 75 Ohm options, along with a comprehensive selection of connectors like N-type, UHF, and BNC. These components are critical for maintaining signal integrity and minimizing loss in antenna systems, whether for a home shack or a remote DXpedition setup. The company's focus on _RF Coax cables_ and connectors directly supports the needs of radio amateurs seeking reliable transmission lines for their transceivers and antennas. Amateurs often compare Voldatech's offerings to established brands, evaluating factors such as impedance matching, shielding effectiveness, and durability under various environmental conditions. The availability of diverse cable types allows operators to select optimal solutions for different frequency bands and power levels, from QRP to high-power amplifier setups. Their products are particularly relevant for those constructing new antenna arrays or upgrading existing feedline systems, aiming to achieve maximum power transfer and reduce standing wave ratio (SWR) for efficient signal propagation.

A Simple Serial and Sound-Card Interface for the Yaesu FT-857D using an FT232R USB-to-serial bridge chip.