Search results

Demonstrates the construction of a **multi-band HF mobile antenna** utilizing a modified CB whip antenna base. The resource details the process of stripping a commercial CB whip, winding a new helical coil with 0.7mm insulated copper wire, and identifying tapping points for various HF bands. It emphasizes the importance of a rugged, slim design for mobile operation, discussing mechanical length, power handling (up to 200 watts), and coil diameter considerations. The article includes a graphic illustrating the antenna's operational principle, where sections of the helical coil are shorted from bottom to top to maintain efficiency and high Q. The resource presents a practical approach to achieving **band switching** without an external tuner, by manually adjusting tapping points on the coil. It provides a table with reference lengths in centimeters from the feedpoint for 7 MHz (40m) through 28.7 MHz (10m), including WARC bands. The author details mounting techniques, suggesting a Diamond bracket for secure attachment to a vehicle trunk, and stresses the critical role of proper grounding for optimal performance. The design allows for operation on 75m and 80m bands by adding a 110mm steel whip.

Presents _Henry Radio Inc._ as a manufacturer of solid-state RF power amplifiers, detailing their capabilities across HF, VHF, and UHF bands. The company designs and builds custom amplifiers tailored for various applications, including amateur radio, commercial broadcasting, military, scientific, and industrial uses. These amplifiers are manufactured in the USA, emphasizing domestic production. Beyond amplifier manufacturing, the resource highlights Henry Radio's role as a distributor for _Bird RF Test Equipment_, including wattmeters, dummy loads, and attenuators. It also mentions _Tohtsu Coaxial Relays_ and a range of miscellaneous amplifier parts and electronic accessories, providing a broader scope of communication equipment offerings. Additionally, the site describes a trunking two-way radio system operating on the 450-476 MHz band, covering significant portions of Los Angeles and Orange County. This service caters to professional dispatch needs for ambulances, taxis, and other commercial entities, requiring no long-term contracts.

WiNRADiO Communications, a division of Radixon Group, was established in 1996 to commercialize extensive research in radio communications. The company specializes in integrating radio and computing technologies, offering a diverse product range for government, military, security, and amateur radio enthusiasts. Their product line includes the WR-G65DDCe 'EXCALIBUR Sigma' HF/VHF SDR receiver, noted for its capabilities, and the G31DDC EXCALIBUR, recognized for its price/performance ratio in shortwave listening with improved AMS and Noise Blanker features. The company also produces the G39DDC series EXCELSIOR for serious monitoring, WR-G526e/G527e/G528e modular SDR solutions for high-performance applications like phase-coherent direction finding, and the low-cost WR-G305e/G305i VHF/UHF receivers. Professional counterparts, the WR-G315e/G315i, support APCO P25 decoders and trunking options. WiNRADiO's offerings extend to the PFSL-G3 field strength logging system for mobile signal coverage, advanced multichannel telemetry systems like the MS-8323, and specialized antennas such as the AX-31C Log-Periodic and AX-81S active HF antenna. DRM decoder software is available for G3 Series receivers, enabling clear reception of DRM broadcasts. The WSS-420 Weather Satellite Receiving System and various antenna rotators are also part of their product ecosystem. WiNRADiO supports multiple operating systems, with MacRadio for Apple Macintosh users and LiNRADiO for Linux developers, providing drivers and network receiver solutions like the RLX-810.

Examines the practical considerations and technical challenges of deploying mobile antennas for 10-meter operation, particularly for operators on the move. It addresses the inherently _lossy_ nature of shortened, loaded vertical antennas typically used in mobile configurations, encouraging hams to view these limitations as engineering challenges. The resource provides actionable advice on safeguarding vehicle electronics, selecting appropriate cabling like _RG-213_, and properly grounding antenna mounts to the vehicle chassis. Specific mounting strategies are detailed, including roof, trunk lip, and side-mounting for trucks and vans, along with their respective advantages and drawbacks. It emphasizes the importance of a robust ground plane and suggests methods for improving grounding beyond simple set screws. The article also touches on antenna choices, mentioning "bugcatchers" and "Hamstick types" as viable options for 10 meters. Furthermore, the guide transitions to stationary mobile operation, where antenna options expand significantly. It outlines how to deploy portable dipoles or 2-element beams from a parked vehicle, offering practical tips for assembly, storage, and mast guying using simple materials like a concrete block. It notes that a 5/8 wavelength height, approximately **20 feet** on 10 meters, often yields good short-skip and DX performance, even with a take-off angle above **20 degrees**.

Win96 - data management software for the PRO-96 digital trunking scanner

RadioReference.com, scanner frequency and radio communications reference source, with complete conventional frequency assignments, trunked radio system information, frequencies, and talkgroups, FCC License assignments and maps, 10-Code Lists, agency maps, files, downloads, links, and detailed agency information for most public safety, military, and local government activities.

Data Management for the RadioShack PRO-95 Trunking Scanner

Broadcastify currently hosts 7,266 live public safety radio feeds, providing real-time scanner audio for police, fire, and EMS operations. The platform aggregates transmissions from various emergency services, allowing users to monitor local dispatch and response activities across numerous geographic areas. It functions as a centralized hub for streaming publicly accessible radio traffic, distinctly separate from amateur radio operations or traditional _DXing_ pursuits, focusing instead on unencrypted public safety communications. The resource primarily focuses on public safety radio systems, which typically operate on VHF/UHF frequencies, often employing trunked radio system architectures. It does not involve amateur radio bands but rather provides direct access to publicly available emergency service communications. The content is organized into categories like Top Feeds, New Feeds, and Official Feeds, facilitating navigation through its extensive catalog. Broadcastify's utility stems from its efficient aggregation and streaming infrastructure, offering a direct link to local emergency dispatch and response. The platform also details its operational mechanics and lists official providers, indicating a structured approach to content sourcing and distribution.

A scanner resource for the Dallas-Fort Worth Metroplex including trunk information and a live scanner feed.

Radio Management Software for the Radio Shack® PRO-92, PRO-93, PRO-2067, PRO-2053, PRO-95 and PRO-96 multi-system trunking scanners.

Data Management for the RadioShack PRO-93/2053 Trunking Scanner

Win92 - Windows-based data management for the Pro-92/2067 trunking scanner

Mobile antenna placement presents unique challenges for the amateur radio operator, often requiring compromises between RF performance and mechanical considerations. This resource from KV5R.COM offers practical insights into achieving effective installations, drawing on real-world experience with different vehicle types. It details how factors like ground plane availability, proximity to vehicle structures, and antenna type (e.g., **HF mobile**, **VHF/UHF mobile**) influence signal radiation patterns and overall system efficiency. The author discusses common scenarios, from sedans and SUVs to trucks and RVs, highlighting the impact of mounting locations such as the trunk lip, fender, or roof. Specific attention is given to minimizing RF interference and maximizing radiated power, crucial for reliable mobile communications. Understanding the interaction between the antenna and the vehicle's metallic body is key to a successful mobile setup, and this content provides a solid foundation for making informed decisions.

The resource details the construction of a **Hustler-compatible** HF mobile antenna mast, utilizing 1/2-inch copper water pipe and common hardware. It provides a bill of materials, specifying one 10-foot copper pipe, four 1/2-inch copper end caps, and 3/8-inch fine-thread hex bolts and nuts, totaling $8.75 for two masts. The construction process outlines preparing bolts by rounding their heads, drilling 3/8-inch holes in end caps, soldering bolts into caps, and then soldering these cap/bolt assemblies to 5-foot sections of copper pipe to achieve a final length of 54-1/4 inches per mast. The method emphasizes precise soldering techniques to ensure structural integrity and proper fit. The resulting masts are presented as functional alternatives to commercial units, with the author noting their performance is comparable to the "real thing." Installation tips are provided, including the use of braces connected to a trunk lid to mitigate stress on the antenna mount, contrasting this approach with WA8WTE's spring-based method. Photos illustrate the completed mast mounted on a vehicle, demonstrating practical application and support strategies for mobile HF operation, particularly with larger coils and longer whips at highway speeds.

Establishing a robust, interconnected communication infrastructure across challenging terrain, the Island Trunk System (ITS) provides a network of open amateur radio repeaters for general and emergency communications throughout Vancouver Island, surrounding waters, and parts of the lower mainland on the West Coast of British Columbia, Canada. This system, largely off-grid, relies on solar power and batteries, necessitating careful operation, especially during night hours and low solar charging seasons, to preserve its energy resources. Maintaining the ITS involves significant effort from many hams, who appreciate adherence to regulations, including proper station identification. The system hosts a weekly social net every Monday evening at 8 PM, welcoming all participants, and also supports a Vancouver Island Region Emergency Radio Net each Wednesday at 19:15. Experimental projects like the Newcastle Ridge webcams, linked via 5.8 GHz broadband backhaul over 206 km to Nanaimo and Comox, demonstrate the innovative spirit within the ITS community. A new VHF repeater, operating on 146.880 MHz with a 141.3 Hz PL tone, was installed in Tofino, expanding system coverage.

Win92 - windows-based data management for the pro-92/2067 trunking scanner

TrunkStar785D is a high-performance, full-featured software package for Uniden® BC785D, BC250D, BC796D and BC296D digital trunking scanners. Data management, operational control and spectrum analysis features are provided.

Examines the four basic components of a mobile antenna system: the antenna, coaxial cable, antenna stud, and the mount, emphasizing mount selection as the most complex decision. Modern vehicle designs, including the absence of metal rain gutters and specific trunk configurations, often preclude traditional mirror, trunk lip, ball, or gutter mounts, necessitating universal mount designs. Discusses the economic challenges of designing vehicle-specific mounts due to tooling costs versus production runs, citing exceptions like Dodge Ram hood mounts and GM truck mirror mount brackets. The article acknowledges the difficulty for manufacturers to recommend specific mounts without direct vehicle inspection, given the vast array of vehicle designs and individual installation restrictions. Advises users with mechanical aptitude to study available mounts and assess possibilities directly on their vehicle. Recommends visiting a local communications store for personalized assistance if self-assessment proves difficult, highlighting the value of expert advice to avoid performance issues or equipment damage.

TrunkStar780%u2122 is a high-performance, full-featured software package for Uniden® BC780XLT trunking scanner. Data management and operational control over the BC780XLT is provided.

Codec2 is an open source low bit rate speech codec designed for communications quality speech at 2400 bit/s and below. Applications include low bandwidth HF/VHF digital radio and VOIP trunking.

The Pro 95 is a dual trunking handheld scanner designed by GRE and sold by Radio Shack

Eham user reviews for Radio Shack PRO-94 1000 channel Dual Trunking Scanner

This page is devoted to the state of Maryland. It contains links for Trunktracker information and conventional data, along with amateur radio sites

This article published on QEX details measurements of tree conductivity and permittivity at HF frequencies, addressing a long-debated topic in amateur radio. N6LF conducted experimental impedance measurements on Douglas fir and maple trees using a vector network analyzer with rings of nails inserted into tree trunks. Results showed that tree conductivity increases with frequency while relative permittivity decreases, similar to soil characteristics. Measured conductivity ranged from 0.06 to 0.4 S/m at 10 MHz, aligning with values used in previous research. These findings validate that NEC modeling can reliably estimate trees' substantial impact on HF antenna performance.