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Learn how an experienced ham radio operator designed and built a compact shack in their motor home. Discover the considerations, challenges, and solutions involved in setting up a radio station in a small space without damaging the vehicle. Find out which radios were chosen for VHF/UHF scanning, HF communications, and QRP operations. Get insights on cabinet design, speaker placement, and radio cabling for a functional and portable ham radio setup on the road.

Demonstrates the capabilities of DXtreme Monitor Log 14, a specialized software application designed for radio spectrum monitoring and logging. The resource details its core functionality, which includes logging stations across various bands and supporting multiple transmission modes such as AM, CW, FM, LSB, USB, and RTTY. It highlights features like the ability to select country formats for new databases and the **Schedule Checker** tool, which assists users in identifying broadcast stations for monitoring. The software facilitates tracking **Maidenhead grid squares**, particularly useful for VHF and UHF monitoring activities. It also supports QSL management and offers tools for efficient contact logging, catering to both amateur radio operators and shortwave listeners. Specific information includes its version number, Monitor Log 14, and its utility for DXers and other radio enthusiasts in managing their monitoring experiences and logging contacts effectively.

Ham radio communication in the VHF and UHF bands, which was previously dominated by analog Frequency Modulation (FM), is increasingly incorporating Digital Voice (DV) modes. DV transceivers digitize audio and offer benefits like as signal integrity, encoded caller ID, and bandwidth savings. Today D-STAR, DMR and Yaesu System Fusion (YSF) are popular DV formats, each with its own set of features but mainly incompatible with the others. Internet access with Voice Over Internet Protocol (VoIP) expands DV communication worldwide. Repeaters and personal hotspots expand DV capabilities, enabling seamless worldwide connections. However, implementing DV frequently necessitates learning new technologies and negotiating network complexity.

English operating manual of the Yaesu FT-818 HF VHF UHF portable transceiver

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.

This PDF presentation explores using aircraft reflections for VHF communication. It explores the characteristics of reflected signals, including how they cause fading and vary in frequency due to aircraft movement. The feasibility of using such signals for communication is then examined. The presentation highlights challenges like requiring very narrow filters and strong frequency stability. It explores Slow-Feld, a slow version of Hellschreiber, as a potential modulation mode due to its tolerance for weak signals and frequency variations. While successful communication via aircraft reflections has been achieved, the data rate was slow and intermittent. The potential for communication over long distances, especially with busy air traffic, is discussed.

This comprehensive article dispels common misconceptions about Standing Wave Ratio (SWR) in amateur radio. The author explains that SWR is not an antenna property but a measure of the entire antenna system, representing the mismatch between transmission line and load impedance. Contrary to popular belief, modest SWR values (under 3:1) typically cause minimal power loss in HF applications. The article demonstrates mathematically why obsession with achieving 1:1 SWR is often unnecessary, explains when SWR matters more (QRO, QRP, VHF/UHF), and explores effective matching techniques including proper ATU placement and quarter-wavelength transformers.

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.

A guide to constructing a simple quarter-wave ground plane antenna, detailing design principles and providing dimensions for VHF/UHF bands

Spectrum Communications specializes in a range of communication products, including antennas and cables for HF, VHF, and UHF (RX & TX), CB radio boards, electronic components, RX & TX boxed products, PCB products, and general accessories for testing and alignment.

A list of HF VHF UHF Beacon list from New Zealand. All beacons from 20m to 3cm

YAGio 1.01 is a Windows-based software for designing DL6WU long Yagi antennas on VHF and UHF frequencies. It supports Windows 2000, XP, Vista, 7, and likely 8. Using keyboard commands, users input specifications such as frequency, gain, and element diameters, and YAGio generates the design. You can download latest Yagio version from this page. Results can be saved in YIO, NEC, YAG, MMA, and YC6 formats, or printed directly.

This article explores the role of velocity factor (VF) in calculating stub lengths for VHF/UHF Baluns. It clarifies misconceptions about VF's relevance, distinguishing between coaxial cable interior fields and external stub fields. Practical examples, such as the Pawsey Stub and Coaxial Cable Balun, are analyzed alongside experimental findings. The results reveal that traditional VF adjustments are unnecessary for stubs with external fields but critical for internal coaxial applications. Historical and theoretical insights provide a comprehensive perspective for antenna enthusiasts and designers.

The Slim Jim VHF antenna, originally designed by G2BCX, is a folded half-wave dipole fed by a quarter-wave matching section. This version, built from a recycled professional aluminum dipole, demonstrates that various materials—such as copper, brass, or twin-lead—can be used. The article details the antenna’s construction, required materials, and tuning process, emphasizing mechanical stability and ease of assembly. With proper adjustment of the feed point, it provides excellent SWR across the band. Its durability and simplicity make it a practical and efficient VHF antenna solution.

Learn how to build a VHF 144MHz transverter connected to an LMR SDR radio using easily accessible components. The transverter works by mixing the 144Mhz input frequency with a 116 MHz local oscillator frequency. Explore the challenges of finding a 116 MHz crystal and the solution of using a programmable Si5351A oscillator. Follow the provided schematic for the RX and TX sections. The transverter design is still a work in progress, with ongoing trials to achieve optimal results.

An owner point of view of the Yaesu FT-818 QRP transceiver capable to work HF VHF UHF in CW, AM, LSB, USB, FM, PACKET.

Twenty 1-watt carbon film resistors are configured in parallel to construct a 50-ohm **dummy load** for amateur radio applications. The design incorporates a heatsink for thermal dissipation and an **SO-239 connector** for RF input, making it suitable for QRP operations. This budget-friendly project details component selection, soldering techniques, and mounting procedures, achieving a continuous power rating of 10 watts and intermittent handling of up to 100 watts across HF and VHF frequency ranges. The resource provides a step-by-step guide for assembly. This construction offers an economical solution for essential shack tasks such as antenna tuning, transmitter testing, and SWR meter calibration without radiating an RF signal. The utilization of readily available components significantly reduces the overall build cost compared to commercial alternatives, providing radio amateurs with a functional and reliable test accessory. While specific VSWR measurements are not provided, the design prioritizes practical utility for low-power transceiver diagnostics and general RF experimentation.

Manufacturer of Foul Weather Whip Antenna a robust, dual-band UHF/VHF antenna with a quick-disconnect BNC connector, offering ~3dBi gain and compatibility with various handheld radios.

Operating amateur radio satellites presents unique challenges, particularly concerning antenna design and signal propagation. Juan Antonio Fernández Montaña, EA4CYQ, recounts his three-year journey into satellite communication, starting with initial guidance from EB4DKA. His early experiments involved a portable 1/4 wave VHF antenna with four 1/4 wave ground planes, designed for hand-held use to adjust polarity. This setup, paired with an FT-3000M transceiver, allowed full-duplex operation on **VHF** transmit and **UHF** receive, proving effective for early contacts on satellites like AO27, UO14, and SO35. EA4CYQ's experience highlights the critical role of coaxial cable loss and antenna polarization. After encountering significant signal degradation with longer RG213 runs, he experimented with a 1/2 inch commercial cable, noting improved reception but persistent fading due to varying satellite polarities. This led to the construction of an **Eggbeater II** antenna, an omnidirectional UHF design offering horizontal polarization at the horizon and circular right polarization at higher elevation angles. Subsequent modifications resulted in the directional **TPM2** antenna, which provided sufficient gain for LEO satellites with a wide 30-degree lobe, enabling consistent contacts from his home station. The article concludes with practical insights on the performance of the Eggbeater II for both UHF and VHF, and the TPM2 for UHF, emphasizing their utility for portable and fixed operations. EA4CYQ's journey underscores the iterative process of antenna development and the importance of adapting designs to overcome real-world propagation challenges in satellite communications.

INTERCOM is a freeware application designed for remote control of KENWOOD TMD700/710/V-71 transceivers, as well as other transceivers equipped with UP, DOWN, and PTT commands. Compatible with Windows XP and higher (32 & 64-bit), INTERCOM offers multilingual support in English and French, and can be used on Linux, Ubuntu, or Android platforms via WINE 1.0 or CROSSOVER. The software enables users to send basic commands—such as selecting TX, VFO, memory channels, or power levels—either through manual inputs or over a TCP/IP link. INTERCOM is tailored for SIMPLEX setups, facilitating the interconnection of VHF/UHF repeaters with nearby repeaters. Remote commands are transmitted using DTMF codes, which are decoded by SIMPLEX and forwarded to INTERCOM via TCP/IP. This functionality makes INTERCOM an ideal tool for radio enthusiasts and operators seeking seamless remote management of supported transceivers in simplex configurations.

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.

The FF-501DX LPF, a high-performance VHF and 10m filter, was obtained at a friend's SK sale. After becoming more active on 10m, the author reexamined the LPF and discovered it to be of high quality. The filter's efficiency was outstanding and the return loss/VSWR was better than estimated. The LPF was connected to a Bird 50R dummy load to evaluate insert loss, cutoff, attenuation over 70MHz, and return loss. The original specifications were found in an old radio magazine, along with a link to the original one-page information sheet. Comparing the results to the original specs confirms the LPF's quality.

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

The author discusses ways to display VHF and higher bands using a K3/10 as  transverter, NooElec Upconverter, SDR, and SDR-Console. He observed that the results were remarkable, with the tuned frequency visible at +/-100kHz. The K3 Interface Option (KXV3A) produces a buffered IF output at 8.213MHz, which is received using a NooElec NESDR SMArt SDR dongle and Ham It UP Upconverter. The SDR-Console program is utilized, with Omnirig synchronizing the SDR and K3. To configure the system, particular parameters are required, such as adjusting the IF frequency to 133.213MHz (125MHz + IF frequency) and inverting the spectrum. The Panadapter demonstrated ES activity at 10m, and modest software tweaks may be required for improved performance.

Kit TNC for HF and VHF packet radio. 300 through 9600 baud. The kit is by TARPN which is a ham radio packet network advocacy group, sold without profit -- order board and CPU from TARPN for cheap. Order the remainder of the parts from Mouser or your preferred local supplier.

Version 1.0.1.0 of QW5 Lizard, released on September 21, 2019, is a specialized logging program designed for Windows notebooks, particularly for outdoor operations and contest participation. It supports individual configuration and input masks, making it suitable for various HF and VHF/UHF contests. The software prioritizes data security, with a planned feature for live upload directly to the GMA database, catering to activations of references such as mountains, WCA, lighthouses, and WWFF. This logging tool offers robust export capabilities, including EDI for NAC and IARU Region 1 Contests, as well as standard ADIF and Cabrillo formats. The program has undergone extensive testing and deployments by various stations, demonstrating its utility in real-world contest scenarios, such as the Holzhammer Contest. Future extensions for specific contests are also anticipated, enhancing its versatility for the competitive ham radio operator.

Terrestrial Amateur Radio Packet Network An ever expanding group of Amateur Radio operators are working together to use many VHF/UHF radios to link multiple ham radio stations in a digital network for the purpose of having fun in a fun, educational, hobbyist-controlled environment, built using ham radio infrastructure based on packet radio technology.

Over 200 distinct 2-meter band amateur radio repeaters are cataloged for Australia, providing essential operational data for VHF communication. Each entry specifies the repeater's output frequency, often including the input tone (e.g., **91.5 Hz** or **123.0 Hz** CTCSS) and the repeater's callsign (e.g., _VK2RSC_, _VK3RHF_). Locations are precisely noted, frequently referencing specific towns, mountains, or geographical features such as "Kinglake, Kangaroo Ground" or "Adaminaby, Mars Hill." The resource also indicates various digital modes and linking capabilities where applicable, such as "FMEchoLinkFusionWIRES-X" or "DMR," alongside standard FM operation. This detailed listing facilitates local and regional VHF communication, enabling hams to program their transceivers accurately for repeater access. The data is presented in a clear, tabular format, making it straightforward to identify repeaters by frequency and location.

EDR-Aalborg was started in 1939 as an association for active radio amateurs. The purpose is to create unity between current amateurs and to give the new ones a good start. The club has radio equipment for HF, VHF and UHF, with all types of modulation. The club's radios can of course only be used by licensed amateurs.

The Texas DX Society, founded in 1970, is a non-profit organization of radio amateurs in Houston, Texas who have a primary interest in DX chasing and contest operating on HF, VHF, and UHF.

Operating an **Echolink** gateway on the 4-meter band presents unique opportunities for extending VHF communications, as demonstrated by the EI4FMG node. Situated at Fieldstown, Monasterboice, this gateway provides coverage across a significant portion of Ireland's east coast, leveraging a Tait TM8100 radio and an EI4JR Echolink interface logic. My own experience with similar setups confirms the importance of strategic site selection for maximizing reach, particularly with a 122-meter elevation above sea level. Access to the EI4FMG gateway, identified by node 57006, requires a **CTCSS** tone of 88.5 Hz, a standard practice for managing access and minimizing interference on shared frequencies. The system transmits with 15 watts of power and utilizes a Sigma CAT70 @5MAGL antenna, a configuration well-suited for regional VHF coverage. The gateway also features an auto-ID every 8 minutes, ensuring compliance and clear station identification. Users can interact with the gateway using various DTMF commands, allowing for connections to specific nodes, random repeater/link or conference nodes, and managing disconnections. These functionalities streamline the process of linking into the broader Echolink network, enabling local VHF operators to communicate globally through the internet backbone.