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Presents the design and performance of a 4-element wire Yagi antenna for the 40-meter band, building upon VE3VN's earlier 3-element switchable wire Yagi. The resource details the antenna's evolution, highlighting the transition from a 3-element to a 4-element configuration and the resulting improvements in gain and front-to-back ratio. It provides specific insights into the antenna's construction and expected operational characteristics. VE3VN shares insights from field results, noting the antenna's performance on 40 meters. The discussion includes the antenna's pattern and matching characteristics, crucial for any DXer or contester looking to optimize their signal on this popular HF band. The author's experience with the previous 3-element design informs the enhancements made to this 4-element iteration. The article includes a visual representation of the antenna's current view, offering a practical perspective on its physical layout. It serves as a valuable reference for hams considering a directional wire antenna for 7 MHz operations, demonstrating a practical approach to achieving enhanced directivity and gain.

The resource details the construction of a 6-meter _Moxon_ antenna, presenting two distinct versions: one horizontally polarized for 50-51 MHz CW/SSB and another vertically polarized for 52-54 MHz FM. It specifies the use of 5/8 inch OD and 1/2 inch OD aluminum tubing, with 3/8 inch OD solid aluminum for corners, and provides a comprehensive material cutting schedule. The design aims for robust, portable construction, with all materials costing under $100. Detailed drawings and EZNEC models are referenced for precise dimensions and assembly, ensuring accurate element spacing and impedance matching. The EZNEC model for the H-POL version predicts a gain of **11 dBi** and a front-to-back ratio of **25 dB** at 50.5 MHz, while the V-POL version shows a gain of **6.7 dBi** and a front-to-back ratio of **36 dB** at 53 MHz. The article includes practical SWR measurement advice, noting the impact of coax length and loss on analyzer readings. Field tests during a tropical storm demonstrated the antenna's durability and performance, yielding numerous contacts across significant distances, including California, Colorado, and Texas, on SSB and PSK.

The 11-meter band, often associated with Citizens Band (CB) radio, presents unique challenges and opportunities for long-distance communication, particularly for operators interested in DXing. This group facilitates discussions and information exchange among enthusiasts who operate on this frequency, often utilizing single-sideband (SSB) modulation for improved range and signal clarity compared to traditional AM CB operations. The community provides a platform for members to share experiences, technical insights, and propagation reports relevant to 27 MHz operations. Members engage in discussions covering various aspects of 11-meter DX, including antenna configurations, transceiver modifications, and operating techniques to maximize signal propagation across continents. The forum serves as a central hub for coordinating contacts, sharing QSL information, and celebrating successful long-haul QSOs. Specific topics often include optimizing power output, reducing noise, and understanding solar cycle effects on 27 MHz. The group's activities extend to organizing virtual gatherings and promoting ethical operating practices within the 11-meter DX community. It supports both seasoned operators and those new to the band, fostering a collaborative environment for exploring the capabilities of CB radio beyond local communications.

Building a PEP Power circuit for all analogue watt-meter

Whether we are tuning up homebrew equipment, checking antenna VSWR, adjusting a linear amplifier, or just monitoring output power during a contest, almost all aspects of ham operation can use a power meter. Paul Wade W1GHZ

Presents the construction of a 10-meter Fractal Quad Yagi (FQY) antenna, detailing the design principles and practical build steps. The article highlights the antenna's compact size, with elements measuring just over 4 feet per side, making it suitable for easy erection and rotation with a TV rotator. It claims an impedance close to 50 ohms, allowing direct feed with 50-ohm coax, and specifies a 3 dBd gain with a front-to-back ratio exceeding 25 dB. Bandwidth is reported at 500 kHz for less than 2:1 VSWR. The resource includes a segment chart (Fig. 1) illustrating the precise lengths for each wire segment of the driven element and reflector, noting adjustments for different wire diameters. Construction utilizes readily available materials such as #9 aluminum ground wire and plastic water pipe for spreaders. The author, _KF7BS_, describes fabricating the framework, bending the fractal elements, and mounting them, including modifications like adding a small stub for reflector tuning. A materials list is provided, detailing items like 40-ft rolls of #9 Radio Shack aluminum ground wire and 1/2-inch plastic water pipe. Scaling equations for the driven element are discussed for different frequencies, such as designing for the CW band. The article references _Chip Cohen NIIRV_'s_ original _Fractenna_ website as the inspiration for the design.

The W4NFR 40-meter mobile vertical antenna project details the construction of a mobile antenna system, drawing inspiration from a July 2011 QST article by VE6AB. The design simplifies the top hat by integrating an 8-spoke top hat from Tar Heel Antenna. The resource outlines the tuning process, which involves adjusting the L1 coil for the desired band segment and then fine-tuning SWR with an L2 coil at the feed point. The author achieved a 1:1 SWR at 7.150 MHz with this configuration. The project includes specific instructions for adding anti-sway supports to ensure stable operation and reduce physical stress on the ball mount during vehicle motion. Visual aids such as drawings of the 40-meter mobile antenna, detailed views of the coil and top hat assembly, and an illustration of the ball and spring mount are provided to guide the builder through the construction and installation phases. The content focuses on practical implementation and tuning for optimal performance on the 40-meter band.

An Attic version for limited space applications by NW9T

A 3 element yagi antenna project for the 144 MHz band by PY5ALZ in portuguese

An home made SWR meter for 2.4 GHz. A DIY SWR meter that allow precise measurements and calibration of any WiFi antenna. This is test equipment everyone who build wifi antennas should have in their shack. Article is in french and include some videos.

A Wifi (V)SWR Meter to build yourself

Design plan of an array of a two element yagis for 80m and a 3 element 40m antenna sharing a single 12 meters long boom by EA5DY

Making your own 2 metre (146 MHz) 5/8th wave whip antenna

10 Meter Easy to build wire dipole antenna

The **2M Moxon antenna** design presented operates at 144 MHz, providing a compact, directional solution for VHF communications. Construction involves aluminum tubing for the elements, with specific dimensions for the driven element and reflector to achieve optimal performance. The design aims for a good front-to-back ratio and a relatively low SWR across the 2-meter band, making it suitable for portable or fixed station use where directivity is beneficial. Element lengths are critical for proper resonance and pattern. The driven element measures approximately 38.5 inches, while the reflector is slightly longer at 40.5 inches. Spacing between the elements is 12 inches, forming the characteristic Moxon rectangle. This configuration yields a gain of about 5.5 dBi and a front-to-back ratio exceeding 20 dB, which is advantageous for reducing interference from unwanted directions. Feedpoint impedance is close to 50 ohms, allowing direct connection to coaxial cable without complex matching networks. The antenna's lightweight structure, typically under 2 pounds, facilitates easy deployment and rotation, making it a practical choice for field operations or as a compact home station antenna.

Near Vertical Incidence Skywave (NVIS) and the 40 meter Novice Sub-band.

EF155A1 21 MHz monobander antenna by YU7EF

picture and dimensions of a coax loop antenna centered at 51.490 MHz

Every ham needs an RF power meter. Here is a high performance unit to build at home.

The circuit is based on two AD8307 log amplifiers, which are connected to the forward and reflected ports on a directional coupler

This homebrew six-meter linear amplifier started off life as a "junker" Alpha 76PA h.f. amplfier. Power output is 800W

January 1955 QST article by W5DQV about constructing a Cubical Quad antenna for 14MHz PDF File

A magnetic loop antenna for 7 Mhz by ZL1BJQ

Presents the DBO274 Citizen Band mailbox, a digital communication hub accessible via HTTP and Telnet, specifically catering to **CB radio** enthusiasts in Germany. This resource outlines its functionality for Packet and other digital emissions on the 11-meter band, a segment often overlooked by traditional amateur radio operators but vital for CB users seeking advanced communication methods. The author, DH8YMB, provides insights into its operation, reflecting practical experience with digital modes in the CB spectrum. The DBO274 serves as a bridge, enabling users to exchange messages and data packets, extending the reach and utility of standard CB transceivers. It represents a localized digital infrastructure, demonstrating how the 27 MHz band can support more than just voice contacts, incorporating elements of early internet-like communication within the CB community. This setup highlights the enduring innovation within the CB realm, adapting technologies like Packet Radio for a different user base. It underscores the versatility of radio communication, even on less conventional bands, for those interested in digital data exchange beyond the typical amateur allocations.

Backpacking, boating or mountaintopping ? Invest your time and pack this novel directional gain antenna on your next expedition

This 40 meter Inverted V antenna was tested and tuned at a height of 35 feet and proved excellent results. The ends of the antenna are about 11 feet above the ground. Article and video available

The two linear amplifiers are ment for use with QRP SSB/CW/FM/AM transmitters on the amateur bands 15 and 17 meters can be powered from a 12 volt DC supply by ON6MU

CB Radio and 10 meter Radio reviews & mods blog. Most articles are in Japanese

5/8 vertical groundplane antenna for six meters band

3 Element reversable quad antenna for 40 meters band

The circuit described below will substantially reduce or completely eliminate interference from almost any local source whilst leaving the wanted signal relatively unaffected, even though it may be on the same frequencey by TREVOR, G3ZYY

Operating on 160 meters from a city lot is always a challenge. Here's how K9YC does it.

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

The 40 meter horizontal loop is constructed from #10 stranded insulated wire available in most hardware stores. The feedpoint uses PVC a pipe T-section. The coax loops through the T-section to provide strain relief by W1TR

A 40/80 meters dipole made with two loading coils based on a project by IK1ZOY

Article on a 2 and 6 meters halo antennas that does not require a mast has a very low part count and can easily be built with a minimum of tools.

2 meter kilowatt linear amplifier

A simple center-fed dipole made just with a thin-wall PVC pipe, aluminum tape, and RG-8X coax

A solutiom for the Ameritron AL-811(H) RF power amplifier, burnt panel meter lights. A common failure with the Ameritron AL-811 and similar amplifiers is that the panel meter lights burn out prematurely. These bulbs are usually integrated into the actual panel meter. The solution for this is to provide the meter backlighting with LEDs.

A home made yagi antenna featuring 6db forward gain and 22 Db front back

The digital wattmeter project was created for the purpose of measuring power in the range of 300nw to 30w.

Building a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

How to build a no tuner 80 meter, half wave wire antenna that takes full advantage of the phone portion of the band known as 75 meters.

A project of a bobtail-curtain antenna for 10 MHz

How to adjust your SWR on your radio and why.

PCB for the DJ9BV Power Meter taken from DUBUS 3/87

RF Power Meter using for reading a standard Digital Voltmeter by Iulian Rosu, YO3DAC / VA3IUL

Presents the construction of a 6-meter (50 MHz) Moxon wire beam antenna, detailing the use of #14 AWG THNN stranded wire and a treated wood frame. It covers the assembly of a galvanized pipe mast, emphasizing the use of pipe sleeves for joint reinforcement over threaded couplers to prevent breakage during raising and lowering operations. The resource also describes the integration of a 1:1 current balun, rated for 50-54 MHz, and the use of RG-8X coax for the transmission line, recommending low-loss alternatives like Belden 9913-7F. Further, it outlines a manual rotation mechanism using pipe hanger clamps and carriage bolts for true North orientation, incorporating magnetic declination calculations from NOAA. The antenna's performance is discussed, noting good gain and take-off angle, with SWR tuning facilitated by a Palstar AT-500 manual tuner. An EZNEC+ 5.054 model for the antenna is available for download, alongside predicted radiation patterns and SWR curves, compared with actual AIM-4170C measurements.

A 2-metre Quad antenna project by K6WXA in PDF file

An 80 meter band vertical loop antenna setup