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Create - Reliable antenna and antenna rotators from japan. Manufacturer of amateur radio products, HF VHF UHF antennas, antnena towers, antenna rotors, HF Log Periodic Antennas, VHF UHF wideband amateur radio antennas

A site devoted to Amateur Radio Homebrewing, CW-decoder, CW QRP Transceiver for the 40 & 20 meters band, CMOS reader

Constructing an HF End-Fed Half-Wave (EFHW) vertical antenna, the resource details the winding of a monoband matching unit, inspired by _AA5TB_, designed to provide a 50 Ohm impedance match without a ground plane or antenna tuner. It specifies the use of a _T200-2_ ferrite core for the transformer, outlining the 13-turn secondary and 2-turn primary winding process with enamelled copper wire. The document also describes the integration of a coax capacitor, whose length is critical for tuning and varies by band, with specific starting lengths provided for 20m, 17m, 15m, 12m, and 10m operation. The practical application section guides the builder through tuning the antenna using an antenna analyzer, emphasizing the iterative process of spacing secondary windings and trimming the coax capacitor to achieve resonance at the desired band frequency. It highlights the antenna's low angle of radiation, beneficial for DX, and claims up to 2 S-points improvement over a _G5RV_ or similar doublet when used as an omnidirectional vertical. A comprehensive shopping list, including specific part numbers from _Rapid Electronics_, is provided, along with advice on selecting fiberglass fishing poles for support and suitable antenna wire.

These are 200 Morse Code QSO`s which might typically be heard on the HF bands.

Demonstrates the construction of a **homebrew spectrum analyzer** designed by Wes Hayward, W7ZOI, and Terry White, K7TAU, enabling radio amateurs to build a capable test instrument without significant expense. The resource details a _double-conversion superheterodyne_ circuit, employing intermediate frequencies of 110 MHz and 10 MHz, and covers essential blocks such as the time base, logarithmic amplifier, resolution filters, and local oscillators. It highlights the use of hybrid and monolithic ICs, including mixers, amplifiers, and VCOs, to simplify construction while maintaining performance. The design supports useful measurements in the 50 kHz to 70 MHz range, with methods outlined for extending capabilities into VHF and UHF. The authors emphasize that this analyzer, while simple to build, is intended for serious measurements, requiring careful control of signal levels to avoid spurious responses. It uses an oscilloscope for display, with specific instructions for calibration and adjustment of various stages, including the log amplifier and IF gain. The guide provides detailed schematics and component lists for each section, such as the 110 MHz triple-tuned band-pass filter, which achieved **90 dB** image rejection, a significant improvement over double-tuned circuits. Practical advice on alignment and troubleshooting is included, drawing on the authors' extensive experience in RF circuit design.

A Portable VHF-UHF Roll-up J-pole Antennam that resonates on both bands but actually performs as a half wave radiator on both bands

Shortened dipole with traps for 40 meters band in portuguese

10 to 20 meters band log-periodic antenna project with SWR Plots, boom lenght and element spacing.

Autotena, a Taiwanese manufacturer, offers a diverse product line focused on RF communication antennas and related accessories. The resource details various antenna types, including **4G/3G LTE wideband high-gain low-profile antennas**, land mobile wideband antennas, fiberglass omnidirectional designs, and GPS mobile and marine antennas. Specific amateur radio offerings include NMO VHF load coil gain antennas, VHF whip gain antennas with PL-259 connectors, and UHF NMO mount antennas with 3dB/5dB gain. The company also produces antennas for CB and 10-meter amateur bands, such as aluminum broadband 26-30MHz antennas and big copper coil broadband 26-30MHz antennas. Additionally, the site showcases **RF amplifiers** for CB, HF, VHF, and UHF bands, including professional-grade base station amplifiers with 100% EIA duty cycle. Handheld antennas, PL-259 type mobile antennas, magnet mount antennas, and external CB speakers are also presented, alongside various mounting kits and cable assemblies.

Here are construction plans of a Turnstile antenna that can be used for space communication on the 2 meter amateur radio band. Specifically for 145.80 mHz

MQ-1 four band HF beams 20,15,10,6 meters MQ-2 six band HF beams 20,17,15,12,10,6 meters, beam antennas and Hybrid Quad antennas

Amateur Radio bandplan in a large PDF A3 format valid for Serbia and Region 2. This band plan can be donwloaded and printed on a color laser printer for optimal quality.

Forum thread about possibility to extend VX-6R to freeband and 6 meters

Operating within the amateur radio HF spectrum requires adherence to established band plans and considerate practices. This guide from the ARRL outlines commonly accepted frequency ranges for specific modes and activities, spanning from 1.800 MHz to 29.680 MHz. It delineates segments for **CW**, **SSB**, RTTY/Data, SSTV, Digital Voice, and AM operations, including dedicated QRP calling frequencies and DX windows. The document emphasizes that these are not regulatory mandates but rather widely recognized conventions, acknowledging that high-activity periods like DXpeditions or contests may lead to temporary deviations. It explicitly references Section 97.101(b) of the FCC Rules, asserting that no station holds exclusive rights to any frequency. The guide also lists frequencies for IBP/NCDXF beacons and automatically controlled data stations. Practical advice is provided regarding frequency selection, stressing the importance of checking for existing use before transmitting. It also mentions ARRL band plans for frequencies above 28.300 MHz, directing operators to additional resources.

An introduction to portable shortwave receivers and sw radio. What to look for in a good portable. Reviews of Sangean ATS505. Band info and frequecies.

A small antenna for all amateur bands, including 80 meters, and in a small garden without the compromise. An ideal replacement for those half size antennas such as the 1/2 size G5RV and Windom 40

A Moxon rectangle antenna projects for the 6 10 15 17 and 20 meter band but include drawings, plans, statistics and homebrewing statistics.

An option for restricted and limited space, to operate the six meters band with an indoor three elements yagi antenna by Brian Williams

Tuning control of the Yaesu FT-736R multiband VHF/UHF transceiver.

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.

End-Fed Half-Wave Antennas (EFHWAs) are analyzed for their utility in portable QRP operations, emphasizing their simplicity, efficiency, and predictable radiation patterns compared to other portable antenna types. The discussion contrasts EFHWAs with vertical antennas, random length wires, and center-fed dipoles, highlighting the common pitfalls of each, such as ground system dependency for verticals and feedline issues for dipoles. The article details the electrical half-wavelength calculation using the formula L (Ft) = 468/F(MHz) and explains how EFHWAs can be resonant on harmonic frequencies, enabling multiband operation. Various deployment configurations are presented, including the inverted L, inverted Vee, sloping wire, and vertical setups, each with specific advantages for radiation angle and polarization. For instance, a vertical EFHWA offers a low angle of radiation suitable for DX contacts without requiring an extensive ground system. The resource also addresses the counterpoise requirements, suggesting a quarter-wavelength wire or connection to a metallic structure for decoupling. A schematic diagram for a simple parallel-tuned circuit tuner, based on the _Rainbow Bridge/Tuner_ design, is provided, detailing component values for 30 and 40 meters, including a 6 microhenry toroidal inductor and a 20-100 picofarad mica compression capacitor. The tuner's adjustment process for SWR matching is also outlined.

Over 75 years of engineering expertise underpins Bird Electronic's offerings in RF power measurement, critical for maintaining peak performance in amateur radio stations and professional communication systems. The company specializes in a range of test equipment, including wattmeters, SWR meters, and antenna analyzers, essential for optimizing antenna systems and ensuring efficient power transfer. Their product line extends to various RF components such as filters, cables, and connectors, all designed to meet stringent technical specifications for reliability and accuracy across diverse frequency bands. Bird Electronic's instruments, like the _Bird 43_ Thruline Wattmeter, are widely recognized for their robust construction and precise measurement capabilities, providing hams with confidence in their station's operational parameters. These tools enable accurate assessment of forward and reflected power, SWR, and modulation characteristics, which are vital for troubleshooting and maximizing radiated power. The company's commitment to innovation ensures that its products remain relevant for modern RF challenges, from HF through microwave applications, supporting both traditional analog and advanced digital modes.

Two element X-Beam is a high-performance broad-band antenna that is ideal for Ham radio operators with limited space. X-Beams are inexpensive and easy to build. The performance of the simple X-beam is amazingly similar to larger, more conventional antennas by 4S7NR

HotPaw MorseDecoder, an iOS application, provides real-time translation of Morse Code audio signals into plain text, leveraging the device's microphone or headset input. It incorporates a DSP narrow-band audio filter, adjustable from 300 to 2400 Hz, to mitigate background noise and QRM, enhancing signal clarity for decoding. The application offers both an automatic decoding mode and manual controls for fine-tuning parameters such as audio filter frequency, WPM dot/dash speed, noise threshold, and Farnsworth timing. The WPM detection automatically adapts from 8 to 40 WPM, with a QRQ High Speed mode extending this range to 30-80 WPM for faster code. A built-in spectrogram aids in identifying the precise audio frequency of the CW tones. User feedback indicates effective performance with various transceivers like the Yaesu FT-857 and Icom IC-R8600, particularly when manual settings are optimized. The app's ability to visually tune stations within the passband and decode speeds beyond an operator's manual capability has proven beneficial during contests and general QRP operation.

A web site dedicated to the K3LR contest station, a Multi Multi Station with 9 towers located in Western Pennsylvania. It provides information about the station components, antenna construction company, radio equipment used, and upcoming events like the Top Band Dinner at Dayton. The site also includes links to related resources like Contest University, Dayton Contest Dinner, and World Wide Radio Operators Foundation. The intended audience is amateur radio operators interested in contesting and DXing. The content is focused on promoting the K3LR station and sharing news and updates related to its activities.

PA3FWM's software defined radio (SDR) page documents his extensive hardware and software development efforts between 2004 and 2009. Initial experiments utilized a direct conversion receiver with 90-degree phase difference, feeding a PC soundcard at 48 kHz sample rate, covering 24 kHz of spectrum around a 7080.5 kHz local oscillator. This setup, similar to AC50G's QEX 2002 article, allowed for basic I/Q signal processing to distinguish signals above and below the LO frequency. Limitations included fixed crystal frequencies, 16-bit dynamic range, and narrow bandwidth. Subsequent hardware iterations aimed for enhanced performance, incorporating external 24-bit ADCs with 192 kHz sample rates, connected via 10 Mbit/s Ethernet. A **MC145170-based PLL** and programmable octave divider provided a 58 kHz to 30 MHz tuning range. The **Tayloe mixer** was employed, with differential outputs feeding a PCM1804 ADC. An ATmega32 microcontroller handled serial data conversion to Ethernet frames, though without CRC calculation due to processing constraints. Later designs integrated AD7760 2.5 Msamples/second ADCs and a Xilinx Spartan-3 FPGA, enabling direct reception of 0-1 MHz spectrum and eventually 2.5 MHz bandwidth across the shortwave spectrum. Software was refactored to use an initial 8192 non-windowed FFT for efficient high-bandwidth processing. The project culminated in a two-way QSO on 21 MHz using the developed hardware and software, demonstrating transmit capabilities with a D/A converter. The system exhibited a 2.5 MHz wide spectrum display and a zoomed 19 kHz display, capturing signals like ionospheric chirp sounders and RTTY contest activity. Challenges included noise leakage from digital circuitry and cooling for high-power dissipation components.

A list of frequencies for ham radio operators QRP operation and with a special reference for those using the Fireball 40 a multi-band QRP TX kit

This PDF document, authored by KT4QW in October 2004, details the construction and modeling of a dual-band, horizontally polarized hanging rectangular loop antenna for **10 and 17 meters**. The design, adapted from *The ARRL Handbook*, utilizes _NEC4WIN95_ software for scaling and optimization, targeting a 50 ohm feedpoint impedance. The resource includes a bill of materials, step-by-step construction instructions, and a discussion of the antenna's radiation characteristics. It presents NEC-generated elevation and azimuth patterns, comparing the loop's performance to a half-wave horizontal dipole at the same height and frequency. The 17-meter element is centered at 18.140 MHz for low SWR across the phone band, while the 10-meter element is centered at 28.500 MHz. Construction involves 14-gauge stranded copper wire and Schedule 40 PVC spreaders, with the total wire length calculated by the formula: Length in feet = 1005/MHz. The feedpoint impedance can be adjusted by modifying the rectangular aspect ratio. The document specifies hoisting the antenna to at least a half-wave above ground for testing. It notes that a balun was tested and found to have no measurable effect on SWR or radiation characteristics. A 2-meter scale model is presented to illustrate the physical design, and a "rotator" string is incorporated for directional adjustment up to 90 degrees.

Mesh constructed with enamelled wire 0.5 mm diameter For installing a support (plastic rope 2 mm) is needed. Antenna used on Solomon Isl in 1995 H44/DJ9RB

Simple, inexpensive and easy to erect, this antenna provides directivity, low angle radiation and a small gain on a number of HF bands.

The Answer To Suburban DXing On the Low Bands - by Merv Schweigert, K9FD

Pictures of the Ameritron AL-811 modification for 10 meter band extension by km5ps

The Buddipole website showcases a range of portable amateur radio antenna systems, including the **Buddipole**, Mini-Buddipole, Buddistick PRO, and BuddiHEX, designed for rapid deployment and multi-band operation from 40 meters to 2 meters. Each product page details specifications, operational modes (dipole or vertical), and compatible accessories like tripods, masts, and baluns. The site also features portable DC power management systems such as the PowerMini 2 and PowerPlus, which include integrated battery chargers and solar controllers, catering to off-grid or field day setups. Instructional videos demonstrate antenna assembly, tuning, and deployment techniques for various configurations, including the VersaTee vertical and Mini-Buddipole. Customer testimonials and DXpedition highlights, such as operations from Montserrat (VP2M) and Dominica (J38), provide real-world examples of the equipment's performance in challenging environments. The company, established in 2001, emphasizes modularity, versatility, and efficiency in its product line, all manufactured in the USA. Shipping information, a 30-day return policy with no restocking fee, and contact details for their Heber City, Utah facility are clearly presented. The site serves as a direct sales portal, offering a comprehensive catalog of antennas, power solutions, and components for portable amateur radio enthusiasts.

Elelement yagi beam antenna for 2 meters band by ON6MU

This DIPLEXER separates 2m from 70cm on the same coax cable, and allows to use 2 antennas over the same cable and permits transmission on one band and simultaneous receiption on the other band by hb9abx

How to build a high gain vertical antenna for the UHF amateur or CB Bands, by radio experimenters handbook

The document discusses a two-element parasitic Delta-Loop array for the 40 meters band, aimed at radio amateurs interested in antenna projects. It provides detailed plans and instructions for building a homemade Delta-Loop antenna.

The Dual-Band Wire Beam was inspired by L.B. Cebik's (W4RNL) article The Elusive Moxon Nest. Fiberglass tubing spreaders, Flexweave elements, an aluminum hub, and two die-cast aluminum flanges combine to provide a 12/17m Moxon nest with one 50 ohm feed.

A project for a 144 Mhz halo antenna

Current HF band conditions online report and graphs. This page provides band condition information to CW and SSB Contesters. It can also be of benefit to other Radio Amateurs to determine band condtions for Nets and casual QSO

AM loop antenna for 75/80 meters band

Faqs on six meters band, designed to help encourage hams to use and enjoy this band

Band Master is a program for Radio Amateurs that downloads DX spots and displays them in different ways, including a graphical band map. It can be used either as a stand alone application or as part of a logging or contesting software. Price USD 25

Accessories for your hamshack, such as Band Decoders, various types of Antenna Switches, Antenna Stacking devices, special devices designed dedicated for the SO2R operating technique, USB Interfaces, cw keyers and many others

Presents _DirLog_, a freeware logging application specifically developed for the 11-meter CB band, catering exclusively to members of the _Alfa Tango Group_. The software facilitates the recording and management of contacts, providing a dedicated tool for CB operators to maintain their station logs. Its development spans from 1997 to 2025, indicating a long-term commitment to its maintenance and evolution by its author, 1AT069 Enio. This specialized logbook offers features tailored for CB operations, allowing users to track their contacts within the 27 MHz band. While primarily focused on CB logging, its structure and functionality could be compared to amateur radio logging software in terms of data entry and retrieval. The exclusivity to Alfa Tango members suggests a community-specific utility, fostering organized record-keeping among its users.

Antenna Warehouse provides a range of certified quality wire products for amateur radio and general communication applications. Their inventory includes Francis antennas, known for their robust construction, alongside the versatile Select-A-Tenna series. The company also stocks Solarcon 10/11 meter base antennas, catering to specific band requirements for 27-28 MHz operations, and various Wilson antenna models. Beyond product sales, Antenna Warehouse offers services such as antenna tower installation, repair, and removal. These services support the complete lifecycle of antenna systems, from initial setup to maintenance and decommissioning. The product selection emphasizes components for both fixed station and mobile installations.

CB2HAM is a group for licensed radio amateurs focussed on converting quality CB radios over to the Ham bands.

A suitable high gain 70cms antenna for SOTA operation was sought that did not have the drawbacks of a long Yagi antenna, principally a narrow beamwidth and bandwidth.

Illustrates the global distribution of **DX-Cluster** nodes through an interactive map interface, enabling radio amateurs to visualize and access real-time DX spots. The resource provides direct TELNET and HYPER links for each node, facilitating immediate connection to various clusters for up-to-the-minute propagation information and station activity. This visual approach simplifies the process of locating and connecting to a suitable DX-Cluster, whether for local or international DXing. Amateurs can use this tool to quickly identify active clusters in different geographic regions, which is particularly useful for **DXpedition** planning or contest operations. The direct links streamline access, bypassing manual configuration for many cluster types. It serves as a practical aid for operators seeking to monitor band conditions, find rare DX, or participate in competitive operating events by leveraging aggregated spotting data.

G7LRR Amateur Radio Site,160m Helical Antenna