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This resource, a blog from the Penang Amateur Radio Club (PARC), offers insights into various aspects of amateur radio in Malaysia. One post details monitoring Automatic Terminal Information Service (ATIS) on the 2m band, providing specific frequencies like 122.750 MHz AM for Butterworth and 126.400 MHz AM for Penang, along with sample aviation weather and operational data. Another entry critiques the lengthy and costly process of obtaining an amateur radio license in Malaysia, contrasting it with the more streamlined FCC licensing system in the United States, citing a 1-year wait and RM 414 (USD 125) for 10 years in Malaysia versus 3 weeks and USD 14 for 10 years in the US. The blog also covers internal club matters, such as the 2007 Annual General Meeting (AGM) attendance and council elections, highlighting member dissatisfaction with outdated newsletters and a call for "reformasi." Additionally, it presents local phonetic alphabets in Bahasa Malaysia and Chinese, and discusses monitoring AM broadcast bands for international stations like Voice of America on 1575 kHz and Zhong Yang Ren Min Guang Bo Dian Tai on 1134 kHz, offering alternatives to local 2m repeater chatter. The author, "firstclass," shares personal observations and criticisms regarding the Malaysian ham radio landscape.

Understanding the operational impact of Broadband over Power Line (BPL) on amateur radio communications is crucial for any radio amateur, especially given the potential for significant radio frequency interference (RFI). This ARRL tutorial delves into the technical aspects of BPL, explaining how the technology operates by transmitting data over existing electrical power lines, which can inadvertently radiate broadband noise across various amateur bands. My own field experience, particularly on the lower HF bands, has often involved tracking down noise sources that exhibit characteristics consistent with BPL emissions, making this a pertinent topic for maintaining clear receive conditions. The resource further details the specific FCC rules and regulations implemented to restrict BPL deployment. These regulations aim to protect licensed radio services, including amateur radio, from harmful interference. It outlines the technical standards and operational limitations imposed on BPL systems to minimize their impact on the electromagnetic spectrum, a critical aspect for contesters and DXers alike. For those engaged in RFI mitigation, the tutorial provides a foundational understanding of the regulatory framework that can be leveraged when addressing BPL-related interference issues. It serves as a valuable reference for hams seeking to comprehend the technical challenges and regulatory solutions surrounding this pervasive noise source.

Demonstrates the swift setup process for a **Trans World Antenna**, showcasing its utility for portable amateur radio operations. The video highlights the antenna's design for quick deployment, a critical factor for activations like Summits On The Air (SOTA) or Parks On The Air (POTA), where efficiency in establishing a station is paramount. It illustrates the physical components and the sequence of assembly, emphasizing ease of use in varied field environments. The antenna system is presented as a multi-band solution, capable of operating across various HF frequencies. This adaptability makes it a versatile choice for hams engaging in outdoor activities or emergency communications. The visual demonstration provides practical insights into managing the antenna elements and feedline for optimal performance during temporary deployments. The focus remains on the practical aspects of field setup, rather than detailed technical specifications or performance metrics.

An automatic band decoder made into a nice enclosure with LED indicators for the chosen band

The page provides detailed instructions on how to build a 60 meter End Fed Half Wave Antenna Tuner, with large pictures and diagrams. It is aimed at amateur radio operators looking to construct their own antennas for the 60 meter band.

An easy to build dipole for 21 and 14 MHz with traps made by two T50-6 toroids cores mounted on a simple PCB foil

The M0PLK multiband delta loop antenna project details the construction of a non-resonant, bidirectional antenna designed for 20-10m operation, requiring an external antenna tuner. The design utilizes two 5.65m aluminum tubes arranged at right angles, with 2x 2.80m antenna wires converging into a 2.30m ladder line, feeding a 1:4 balun. The resource provides a comprehensive parts list, including specific dimensions for aluminum tubes (25mm, 20mm, 16mm outer diameter), DX-Wire FS2, and custom 3D-printed components like a middle insulator, tube end caps, and ladder line spacers, with STL files provided. Construction steps cover base plate fabrication from a 300x300x4mm aluminum sheet, balun assembly, tube preparation with slits and threaded holes, and wire attachment with strain relief. Initial VSWR measurements are presented, indicating performance in line with expectations across the target bands. The author reports successful SSB test QSOs to the USA on 10, 12, 15, 17, and 20m immediately after completion. The project highlights the antenna's bidirectional pattern, noting the need for a lightweight, remote-controlled rotator to fully utilize its directional capabilities. Comparisons are drawn to the Cobweb antenna, with the M0PLK design cited for its reduced local QRM pickup. The article references external sources, including M0AWS's detailed report and PC modeling, along with other construction variants and commercial assembly instructions, providing a robust foundation for replication.

Homebrew 30 meter full quarter wave vertical antenna.

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

This version of the broadband hexbeam is based on the work of Hunt G3TXQ, HB9MCZ, and Shoemaker K4KIO. EZNEC model is based on a wider element spacing than the version published in QST by K4KIO

The TransWorld Antennas TW4040 The Adventurer Monobander™ is a portable HF antenna designed for rapid deployment in field operations, including **SOTA** and **POTA** activations. This manual details the antenna's assembly, tuning procedures, and operational guidelines for optimal performance on the 40-meter band. It outlines the specific components, such as the telescoping whip and base unit, required for proper setup. Instructions cover mast erection, radial wire deployment, and impedance matching to achieve a low **VSWR** across the designated frequency segment. The document also provides guidance on antenna orientation and environmental considerations for portable use. It specifies the antenna's power handling capabilities and physical dimensions when fully deployed and collapsed for transport.

A 600W 1.8 MHz to 54 MHz power linear amplifier made using rugged MRF300 transistors featuring output power between 580W and 750W depending on band, power supply: 48V, 18A typical, 20A max

Changing band selector to a Kenwood TL-922 power amplifier by IW1PUR in italian

A homemade band pass filter for the 30 meter band based on the original VE7BPO design

Review of the Retevis RT95 also marketed as Anytone AT-778UV dual band VHF UHF FM mobile radio transceiver

Such kind of omnidirectional antenna gives the possibility to be QRV with horizontal polarisation, as commonly used for the CW and SSB section of the 2m band. This actual design shows a 1.3:1 bandwidth of about 150kHz, centered to 144.200MHz.

A shielded broadband (~200 MHz) active loop antenna offers more quiet and relatively less interference reception.

Demonstrates a specialized DX cluster monitoring application, _DxWatcher_, designed for Windows environments. It processes DX spots received via Telnet/Internet, presenting them in a filtered table and a dynamic bandmap. The software integrates with transceivers, specifically the FT-2000, to read VFO frequency and enable one-click tuning to spotted stations. _DxWatcher_ version 1.0.3.0, released on 13 June 2020, includes minor bugfixes and improvements such as enhanced recovery from suspend mode. Key features include configurable bandmap position and size, automatic opening, and bolding of spots received within the last **10 minutes**. The application utilizes the standard _ctry.dat_ file for DXCC country analysis, allowing users to update it for current DXCC status. Source code, developed in C# with MS Visual Studio 2008, is freely available, encouraging modification and sharing while requesting retention of the original author's callsign.

The 7-minute, 52-second video, published on December 31, 2016, by TheStingyHam, details several methods for optimizing receive audio on the **Elecraft KX2** QRP transceiver. It specifically addresses challenges encountered on the 40-meter band, a common haunt for QRP operators, while also noting that 15m and 20m operations might benefit from different settings, such as combining the preamp with receive EQ and RF gain adjustments. Key moments highlighted in the video include specific adjustments for noise reduction, filter settings, signal attenuation, and receive equalization. These techniques are demonstrated to help operators extract clearer signals from a noisy band, a critical skill for successful portable operations and DXing with low power. The author, drawing from field experience, suggests that while the tips are primarily aimed at 40m, the underlying principles of careful audio and RF gain management are broadly applicable across the HF spectrum, enhancing the overall QRP operating experience.

The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.

This wire antenna for 40 and 20 meter band feature a good SWR. Horizontal side of the antenna is placed at two meters above the ground. Impedance of the antenna are depending by the height of the base from the ground and conditions of the ground

The 160-meter amateur radio band, spanning 1.8 to 2 MHz, was historically the lowest frequency amateur allocation until the introduction of the 630-meter and 2200-meter bands. ITU Region 1 allocates 1.81–2 MHz, while other regions use 1.8–2 MHz. This band, often called "Top Band" or "Gentleman's Band," was established by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927, with an initial allocation of 1.715–2 MHz. Effective operation on 160 meters presents significant challenges due to the large antenna sizes required; a quarter-wavelength monopole is over 130 feet, and horizontal dipoles need similar heights. Propagation is typically local during the day, but long-distance contacts are common at night, especially around sunrise and sunset, and during solar minimums. The band experienced a resurgence after the LORAN-A system was phased out in North America in December 1980, leading to the removal of power restrictions.

Fine tuning your Multiband Hustler Vertical

The BTech DMR-6X2 dual-band DMR handheld radio is thoroughly reviewed, detailing its features and performance for amateur radio operators. This resource covers the radio's capabilities for both VHF and UHF frequencies, supporting Tier II DMR digital and FM analog modes. It highlights key specifications such as its **136-174 MHz** and **400-480 MHz** frequency ranges, CTCSS/DCS, DTMF, 2-TONE, and 5-TONE signaling, and its _digital simplex repeater_ function. The review provides a comprehensive unboxing experience, listing included accessories like two Li-Ion batteries (2100 and 3100 mAh), a programming cable, and a 37-page English user guide. It also specifies the radio's physical dimensions of 5.1 x 2.4 x 1.5 inches and weights of 9.9 oz with the 2100 mAh battery and 10.8 oz with the 3100 mAh battery, offering practical insights for hams considering this transceiver.

A 2m band Moxon antenna design is presented, centered at 145.2 MHz, with dimensions derived from Moxgen software. The design features a calculated 6 dBi gain, an 80-degree beamwidth, and an impressive 43 dB front-to-back ratio with minimal back lobes, concentrating RF energy in the forward direction. The antenna is balanced to 50 Ohms, facilitating direct feed. SWR sweep data from 144 MHz to 146 MHz demonstrates a near 1:1 SWR at the center frequency, maintaining healthy SWR values across the entire 2m amateur band. This performance is comparable to a 3-element Yagi, yet the Moxon offers advantages in compact size and ease of mast mounting, making it suitable for various operating environments.

VHF Broadcast Passband Filter (88 108 MHz) by DF9CY

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

A review of all possible receiving antennas for top band 160 meters

Homebrew Amateur Radio 440Mhz Interdigital Bandpass Filter

A interesting guide to help get started with HF published at Essex Ham

The construction principles for open-sleeve elements in antennas

The SDRanywhere application facilitates remote control of RFSPACE SDR hardware, specifically the SDR-IQ, NetSDR, SDR-IP, and Cloud-IQ models, from any location worldwide. This Android app compresses and transmits both demodulated audio and waterfall spectrum information to the client over a low-bandwidth internet connection, making it practical for mobile or remote operations. The system is designed to allow users to monitor and operate their SDRs without being physically present at the radio's location. This capability is particularly useful for DXers and contesters who need to monitor band conditions or operate a remote station. The application's ability to function with limited bandwidth ensures reliable performance even in challenging network environments. The associated web page displays a live monitor of active SDR nodes, detailing their status, port, and geographical coordinates, such as the "Smola 315 deg ant #2" node operating on port **8021** or the "Karelia MW DX, Finland" node on port **50000**.

The RSGB Band Plan is normally published annually in the February edition of RadCom and additionally reviewed mid-year. It is derived from the IARU Region 1 Band Plan taking into account any proposed national variations or special amendments, which are considered necessary by the relevant spectrum manager.

A dipole can be broadbanded by a number of techniques including by matching with resonant sections of transmission feed lines.

Wideband receiving phased arrays with small electric or magnetic active wideband elements are discussed in details. Practical results and examples are given.

5 Elements 12,5 Ohm Yagi with a 6m Boom

An interesting presetnation full of usefull tricks to correctly design and build 23 cm Yagi using simple tools. The basic design of the antenna presented in this document is taken from the original DL6WU Yagi Design published in 1982

Performance data of the KIO Hexagonal Beam antenna

Freeband modification for the Yaesu FT-100

Encouragement for Little Pistols, article originally written for and published in SKIP the monthly newsletter of the Fresno Amateur Radio Club

Presents the K9AY Loop, a compact, directional receiving antenna system optimized for low-band operation, demonstrating its design and construction. The resource details the physical and electrical simplicity of the terminated loop, which consists of a wire loop, a ground rod, a 9:1 impedance-matching transformer, and a terminating resistor. It compares the K9AY system's real estate requirements to an equivalent EWE array, showing it needs only one-seventh the area while providing identical directional patterns. The article includes schematics for the relay box and control unit, specifying components like DPDT relays, steering diodes, and a 43 material toroid for the matching transformer. The resource provides practical construction steps, including material lists for two 85-foot wire loops, insulators, a copper ground rod, and a 25-foot support. It discusses the critical role of the terminating resistor (RTERM), with values ranging from 390 to 560 ohms for 160m and 80m optimization, respectively. Performance evaluation methods are outlined, suggesting listening tests with local AM stations or WWV to verify front-to-back (F/B) ratios of 2 to 3 S units. EZNEC modeling results for vertical and horizontal radiation patterns are presented, showing a broad front lobe and a deep rearward null at 30-40 degrees elevation, crucial for reducing local noise and QRM.

These are QRP rated 3 Pole Butterworth filters based on a design by K4VX, feature simplicity, almost no insertion loss, and reasonable rejection on the other ham bands.

Adding a full power output 12 meter band capability to the Yaesu FL-2100 despite of 10 meter.

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.

Homemade LC Bandpass Filters for 20M, 30M, 40M In multi-station environments like special events, field day, portable operating, is very important to protect receivers from excessively strong signals. Bandpass filters help to protect your transceivers.

An interesting article about low band receive antenna for Urban QTHs

MMSTV help pages, describing how to setup and run this sstv program by Andrew O'Brien

160 to 40 meters inverted L antennas projects

A monoband delta loop antenna for the 7 MHz. This vertically polarized DX Antenna is a full wavelength sngle side antenna and has a total length of 42.3 meters (137,1 inch) Can be easily setup with a flag pole or fishing pole as center top mast. For optimal performance lower side should be at 2 meter above the ground. This antenna offers a low radiation angle and 1 DB Gain.

An home made doblet antenna made with two Slinkys that are aproximately five meters in length connected with a twin-feed connected to a balanced ATU