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Skin effect and proximity effect on making coils with stranded wire. An interesting comparison on making coils.

For over 20 years, bhi Ltd has specialized in digital signal processing (DSP) technology to mitigate noise and interference across various radio channels. Their product line, including the _ParaPro EQ20 Audio DSP_ units, focuses on enhancing receive audio quality, even for operators without significant noise issues, by offering precise parametric equalization to suit individual hearing preferences. The core offerings are noise-cancelling speakers and in-line modules, specifically engineered for amateur radio applications, but also adapted for commercial, PMR, and marine radio systems. The company provides audio demonstrations, such as a 20m SSB example and a 14MHz band filter comparison, allowing users to hear the effectiveness of their DSP units against common QRM sources like plasma TV interference or diesel engine noise. Located in Burgess Hill, West Sussex, UK, bhi Ltd emphasizes clear voice communications, aiming to remove unwanted noise and leave only intelligible speech.

The **136kHz Vertical Antenna** at G3YMC employs a Butternut HF2V structure, standing 10m tall. It integrates a 6.5mH loading coil to achieve resonance, with a matching transformer for impedance adjustment. The antenna's configuration includes top loading via a 12m horizontal wire, enhancing capacitive impedance. Initial measurements indicated a high impedance of around 300 ohms, necessitating a transformer for a 50-ohm match. Despite challenges with ground losses, the vertical antenna has shown improved performance in specific directions, filling nulls present in the previous loop antenna setup. The tuning remains broad, with variations due to environmental factors affecting the matching. Ongoing adjustments and comparisons with the loop antenna will continue to refine its effectiveness.

Comparison of FT-1000D FT-736R FT-817 FT-847 FT-897 IC-765 Orion TS-2000 Spectral purity of a continous carrier, of a SSB and CW signals

During a club's "Filetto Day" event, a comparative field test was conducted between a **Buddipole** antenna and a homemade 20/40-meter wire dipole. The author, IW5EDI, performed this personal evaluation from a mountain top at 1500 meters above sea level, utilizing a Yaesu FT-857D transceiver to switch between antennas. The observations on the 20-meter band indicated that the wire dipole consistently delivered significantly stronger signals compared to the Buddipole. Additionally, the Buddipole exhibited higher levels of **QRM** during the listening tests. The commercial Buddipole, known for its multiband capability and compact size with a self-supporting tripod, was contrasted with the simpler, larger wire dipole, which required a fiberglass fish pole for support. This direct comparison highlights practical differences in performance and deployment between a popular portable commercial antenna and a basic wire antenna in a real-world operating environment.

A test and comparison of real attenuation of N-type connectors and PL-259 connectors on UHF bands, domonstrating that connectors are almost equivalent.

Here a comparison of Kenwood TS-590S used with MC-60A and the oringina dynamic microphone

The Buddipole Deluxe, a portable HF/VHF antenna system, receives a practical assessment from IW5EDI after a month of field use. The author, constrained by antenna restrictions, highlights the system's crucial role in enabling portable operations, even managing sporadic digital activity from a balcony. Direct comparisons to a fixed 3-band dipole reveal surprisingly comparable signal reports on 15, 17, and 20 meters, underscoring the Buddipole's effectiveness in real-world scenarios. Tuning the Buddipole proves straightforward on bands down to 20 meters, though the review notes significant challenges with SWR on lower bands like 40 meters, where achieving better than 3:1 SWR was problematic. Observations also include SWR variations with dipole rotation and mast height, suggesting environmental factors play a role. The overall manufacturing quality of the antenna and its accessories, including the tripod and carry bag, is deemed good, despite a minor issue with a pole connector. Looking ahead, the author plans to construct a homemade Buddipole version, possibly optimized for the 30-meter band, specifically for PSK31 operations from an apartment. This personal project reflects a common amateur radio practice of adapting commercial designs for specific needs, further extending the utility of portable antenna concepts.

Comparison of all the oscilloscopes available for hobbyists, digital oscilloscopes that you can get for under $500, or oscilloscopes that you can build yourself.

Presents an Italian association, Club 27 Catania, which is affiliated with Protezione Civile FIR-CB. The resource indicates a focus on CB radio and various DX groups, including Papa Alfa Tango, Wisconsin Michigan, Charly Tango, Oscar Sierra, Big Time Operators, WAC Club, Azteca DX, and TX&RX Group. The page itself is a placeholder, stating "We’re getting things ready" and "Loading your experience… This won’t take long," suggesting future content will detail the club's activities and affiliations. The current state of the resource provides minimal information beyond its name and affiliations. It does not offer details on club events, membership, technical discussions, or operational specifics. The listed DX groups imply a focus on long-distance communications within the CB radio spectrum, but no specific results, comparisons of operating techniques, or practical applications are available on the present page.

Kenwood TS-590S QST review comments and table comparison vs Elecraft K3

Constructing a compact directional antenna for the 17-meter band, this resource details the build process for a Moxon rectangle, a two-element Yagi variant with folded-back elements. It covers the antenna's evolution from the _VK2ABQ beam_ and provides specific dimensions for a version built using fishing pole whips. The content includes a discussion of the antenna's radiation pattern, feedpoint impedance, and its inherent front-to-back ratio, which is often superior to a standard two-element Yagi. Practical considerations for element spacing and material choices are also addressed, alongside a visual representation of the antenna's physical layout. Performance data presented includes a comparison showing the Moxon rectangle's **2.5 dB gain** over a half-wave dipole and a front-to-back ratio of **20 dB**. The resource also touches upon the antenna's relatively wide bandwidth for a two-element beam and its suitability for portable operations due to its compact footprint. It offers insights into optimizing the design for specific operating conditions and discusses the advantages of its lower take-off angle compared to omnidirectional wire antennas, making it effective for DX contacts on the 17-meter band.

This resource, intended to present historical score records for the _ARRL International DX Contest_, currently displays a "Page not found" error. The page's original purpose was to document top scores and records for both Phone and CW segments of the contest, offering a historical perspective on competitive amateur radio operating. Without the content, no specific technical details regarding past contest results, callsigns of record holders, or score breakdowns can be extracted. The resource's current state prevents any analysis of score comparisons, operational strategies of top stations, or the evolution of contest performance over time.

Yaesu FTDX10 vs. ICOM IC-7300 Comparison Chart and review of reception performances

A 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

Two different ways to create autotransformer for end fed half wave wire antennas, by using ferrite or air core.

Evaluates the **LDG Z100 autotuner**, a device designed to automatically match antenna impedance for optimal transmission efficiency. The review discusses its performance in comparison to the MFJ-902, noting that while the Z100 is a reliable autotuner, it does not match the range of impedances that the MFJ-902 can handle. The Z100 is suitable for operators seeking a 100-watt autotuner that covers HF bands, providing a practical solution for those who require automatic tuning without manual adjustments. The review highlights the Z100's operational context, focusing on its use in HF bands and its practical application in amateur radio setups. While it offers a straightforward tuning process, the Z100's limitations in impedance matching are noted, making it less versatile than some competitors. This comparison provides valuable insights for operators considering an upgrade or replacement for their current autotuner. The Z100's performance is positioned within the broader market of autotuners, offering a clear perspective on its strengths and weaknesses in real-world amateur radio operations.

A very informative review of the Icom IC-7300 direct RF sampling transceiver, including audio samples, recordings and a comparison vs the Elecraft KX3

A Comparison of most popular Amateur Radio Digital Voice Systems DMR D-Star System Fusion presented by W9HPX Roland at the Charlotte Digital Radio Group in a comprehensive article about Digital Voice

This Microphone comparison article summarizes the test results of two popular ham radio microphones the ElectroVoice RE27 and Heil PR781

Comparison of some popular 432 MHz EME antennas by DF9CY

Jose B Rivera, N2LRB, shares his initial experiences with the Icom IC-7300, recounting a shift from skepticism to appreciation for the transceiver. He details how the radio's impressive Sherwood Engineering test results, ranking it #12, significantly influenced his decision, especially considering its competitive price point against higher-end options like the Elecraft K3s. The review highlights the IC-7300's strong receive capabilities, a key factor in N2LRB's purchasing decision, and notes the advantages of its SDR architecture for future updates. He describes the straightforward setup process, from unboxing and connecting PowerPole connectors to making a first contact with N0HQ, a special event station. N2LRB expresses satisfaction with the radio's clear audio and ease of tuning, even if the pan-adapter's utility for his operating style remains to be fully explored. He concludes that the IC-7300 offers exceptional value, providing SDR features and receive performance comparable to more expensive rigs at half the cost.

BaoFeng UV-5RA, UV-B5, UV-82, and Yaesu VX-6R Comparison

Comparing many antennas for 50 MHz band

The Icom IC-7600 compared to other Icom HF radios , like IC-756Pro III, IC-7700 and IC-7800 by VA7OJ/AB4OJ

Mobile installation of a Kenwood TM-D710 and comparison with the Yaesu FT-350R

A very well done presentation about End-Fed Half-Wave antennas. This PDF document contains a summary of experiences in how to build custom EFHW antennas. Includes an interesting comparison table of UnUn configurations with recommended toroids, Wire size, turns and capacitors. An useful recap on common errors in building homebrew EFHW Ununs completes the document.

CATSync V1.30 integrates OpenWebRX support, expanding its capability to synchronize a local amateur radio transceiver's CAT control with a broader range of public WebSDR receivers. The software facilitates real-time frequency tracking, allowing the operator to adjust their physical rig's VFO and observe the connected WebSDR instantly follow the tuned frequency. This functionality is crucial for remote listening, signal comparison, and verifying propagation conditions across different geographic locations using a familiar hardware interface. The application supports both the classical WebSDR interface and KiwiSDR platforms, providing a consistent control experience across various online SDR deployments. It bridges the gap between local station operation and the vast network of globally distributed software-defined radios, offering a practical tool for DXers and contesters. CATSync is designed for Windows and Linux environments, with Android compatibility noted, making it accessible to a wide user base seeking to leverage WebSDR resources with their existing station setup.

The **LDG Z100 Autotuner** review by GW6ITJ details the unit's practical application and performance in a ham shack environment. Initially acquired to replace an MFJ-902, the Z100 is noted for its ease of use, though the author observes it doesn't quite match the impedance range of the older MFJ unit. This hands-on assessment provides a real-world perspective on its capabilities for 100-watt operation across the HF bands. GW6ITJ specifically mentions the Z100's suitability for 3.5 MHz and higher frequencies, indicating its utility for common HF operations. The review focuses on user experience rather than technical specifications, directing readers to the LDG website for detailed data and manuals. This approach highlights the tuner's operational characteristics from a user's perspective. The author's experience with the Z100 suggests it's a reliable choice for general amateur radio use, particularly for those seeking a straightforward autotuner. The comparison to the MFJ-902 offers a valuable benchmark for hams considering a similar upgrade or new acquisition, emphasizing practical differences in impedance matching.

An in-depth comparison here between the various digital technologies

Articles on the correct placement of ferrite noise suppressors are common, but little has been written about the different options and where to buy them. This page contains an interesting comparison of several ferrite types used to reduce RFI.

Identifying The Drake TR-7 Differences and Versions

The Red River Valley Amateur Radio Club Paris, Lamar County, Texas

A comparison of commercial 4m verticals by by Ian Hogan G6TGO

The current page presents a domain name for sale, rather than providing amateur radio content. It outlines the process for acquiring the _ae5x.com_ domain, including a direct purchase price of **$3,795** or a 24-month payment plan at $158.13 per month with 0% interest. The service emphasizes quick delivery, secure shopping via SSL encryption, and a 30-day money-back guarantee. Information regarding domain transfers to other registrars like GoDaddy is provided, noting that transfers can take up to 5 days and payment plan domains are ineligible until fully paid. The purchase includes only the domain name, with hosting and web design services needing to be sourced separately. Privacy protection options through NameBright.com are also mentioned.

The W6JWS 2-meter Repeater Maintenance and Repair Log documents the ongoing upkeep of a 146.745 MHz repeater, specifically addressing modifications to enhance its functionality. It details changes made to ensure the repeater powers up in _PL mode_ and to improve the reliability of touch-tone control, drawing comparisons to similar work performed on the AE6KE repeater. The log also notes a repair to a fused wire in the reverse battery protection circuit after an accidental polarity reversal, highlighting a temporary workaround where a wire was omitted but the system remained operational. The resource includes practical insights from Jeff Liebermann, AE6KS, regarding jumper configurations and programming, with accompanying photos. It provides access to several documents for the Icom RP-1510 repeater, including operating manuals and a schematic for the single logic board version, which differs from the dual-board configuration described in some printed manuals. The log mentions a specific modification to adjust the dropout delay, which was later deemed unnecessary, and references a related project for the AE6KE repeater, aiming to replicate successful modifications on the W6JWS machine, resulting in improved touch-tone reliability and proper PL mode activation.

A comparison of Elecraft KX2 and Yaesu FT-818

This page describes a comparison study on seven different beam antennas for 40 meters band. Yagi antennas, moxon antennas, mini horse all antennas are described with schema diagram , azimuth plot and SWR F/B Gain diagram

Heil Sound PR-35 vs Heil Sound PR-781 vs Electro Voice Blue Cardinal by K4QKY

This paper presents the method of calculating the maximum usable frequency (MUF) and field strength of radio waves reflecting 2 times at the F2 ionosphere layer under inhomogeneous conditions of the ionosphere. The comparison between predicted and measured MUF has shown that the proposed method significantly increases the accuracy of calculation MUF.

An introduction to NPR by Daniel Estevez. In this blog article Daniel EA4GPZ / M0HXM, introduce the new IP communication protocol over the 70 cm amateur radio band. Daniel is an experienced operator on IP on 430 MHz with CC1101 and Beaglebone black project and makes a good comparison of the two projects.

DXLook is a free, web-based propagation platform that delivers comprehensive, real-time insight into HF and VHF conditions directly from any modern browser. It aggregates live spots from PSK Reporter, WSPRnet, RBN, and DX Cluster, complemented by NOAA space-weather metrics such as SFI, K/A indices, and geomagnetic alerts. Integrated VOACAP predictions allow practical "theory versus reality" comparisons, while the interactive world map with filters, gray line, and grid overlays enhances situational awareness. With no installation or maintenance required, DXLook provides a convenient, accurate, and accessible solution for everyday operating and propagation analysis.

On the field comparison among C-Pole antenna, an EFHW vertical antenna and an Inverter V dipole antenna. Test is done using two identical WSPRLite beacons that transmit with 200mW on the WSPR frequency and analyzing spotted results.

Experimental Long Boom Antennas - CP, LPDA, multiband with several NEC Files for 50MHz 144MHz 222 MHz 432MHz but also 902MHz and 1296 MHz Antenna projects. Includes also for each antenna model, in a general comparison table each antenna characteristics including Directive Gain, G/T, E-F/R, H-F/R abd Boom Length. This is a great value comparison table of several commercial and home made VHF UHF antenna projects.

A comparison among a traditional J-Pole Antenna and 2BCX Slim Jim Antenna

A Magnetic Loop Controller project details the construction and operation of an automatic tuning system for magnetic loop antennas, which are resonant circuits using an oversized inductor and an adjustable capacitor. The system employs a stepper motor to precisely adjust the variable capacitor, maintaining optimal resonance across the HF bands. It integrates with various transceivers, including _Icom_, _Kenwood_, and _Yaesu_ models, by monitoring the VFO frequency and adjusting the loop's tuning accordingly. The project provides comprehensive building instructions, a PowerPoint-style presentation, and the full source code for the controller's firmware, enabling hams to replicate and customize the design. The controller's firmware offers diverse functionality, including automatic frequency tracking, manual tuning, and SWR monitoring, significantly enhancing the operational efficiency of magnetic loop antennas, particularly for QRP and portable operations. The design emphasizes accurate capacitor positioning, crucial for achieving low SWR and maximum radiated power. Comparisons with manual tuning methods highlight the benefits of real-time adjustment, especially when operating across different bands or making frequent QSYs. The project's detailed documentation and available source code facilitate experimentation and modification by advanced builders, allowing for tailored performance characteristics.

This study details a reception comparison between vertical and horizontal active loop antennas, specifically two identical _Wellgood active loop antennas_, on various HF bands. The experiment, conducted in a densely populated QRM-prone area, monitored FT8 signals over a 24-hour period using two identical receivers. The methodology involved direct comparison of signal reception across the HF spectrum, aiming to identify performance differences based on antenna orientation. The results indicate that vertical loops demonstrated superior performance on higher bands (10m, 15m, 20m), while horizontal loops excelled on lower bands (30m, 40m, 160m), particularly for receiving long-distance (DX) signals. The horizontal loop's advantage on lower bands is attributed to potentially better low-angle performance and reduced sensitivity to man-made noise, yielding a **2-3 S-unit** improvement on 160m. The study provides practical insights for optimizing antenna placement in challenging urban environments, noting that the horizontal loop consistently showed a **10-15 dB** signal-to-noise ratio improvement on lower bands.

Exploring LoRaWAN Range, comparing the performance of 1Watt and 100mW LoRa trackers on daily commute. Analyzing APRS tracks, beacon statistics, and visual comparisons to uncover insights and surprises in the world of long-range wireless communication.

This project details the construction of a compact, circularly polarized Quadrifilar Helix Antenna (QHA) designed for 146 MHz operation. The antenna features a 1/2λ1/2λ helical design with a 2.6:1 aspect ratio, providing 4.5 dB gain and a spheroid radiation pattern. It is ground plane independent and compatible with both vertical and horizontal polarizations, making it ideal for terrestrial and space communications. The design includes step-by-step instructions for building the antenna using readily available materials like aluminum rods, PVC pipes, and RG-58 coaxial cable. The antenna's performance has been validated through comparisons with commercial omnidirectional antennas, showing superior results.

Discover the best low band receive antennas for hams with limited space. Learn about the K9AY loop antenna and Shared Apex Loop Array, two alternatives to the traditional Beverage antenna. Understand the concept of Relative Directivity Factor (RDF) and compare the performance of different receive antennas. See how the Shared Apex Loop, patented by Mark Bauman (KB7GF), offers an RDF between 8 and 10dB. Find out how to optimize antenna performance and enhance your receive capabilities on 160, 80, and 40 meters. Explore the world of low band receive antennas with insights from WB5NHL Ham Radio.