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A 50.200 MHz Moxon antenna for the 6-meter band is detailed, providing practical construction guidance for amateur radio operators. The design utilizes 3/4" aluminum angle stock for the elements, joined with wood molding and 1/4 x 20 hardware. Key components include an SO-239 connector for the feedpoint and a **choke balun** made from coiled RG-58 coax, ensuring proper impedance matching and minimizing common mode current. The antenna measures approximately 29 inches deep by just under 7 feet long, making it suitable for portable operations. Specific dimensions, based on **Cebik's nomenclature**, are provided for the driven element and reflector. The resource also offers modeling hints, suggesting an effective element diameter of 1 inch for software simulations and emphasizing element sizing based on corner screws rather than end-to-end measurements.

80 watt multi-mode amplifier using one of the newer S-AV36 Toshiba modules. Less than 50 milliwatts will drive it to full output in any mode.

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

A really simple project to make a power meter measuring RF output powers from a few mW up to half a watt. A DIY amateur radio project for QRP enthusiasts

Redesigning CDE rotator control meter scale for north-centered operation

SJ2W Contest Station, antenna for the 160 meter is a 39m vertical. This 160m antenna consist of 29m of WIBE tower sections with an insulated base and 10m top tube.

YT1VP Yagi antenna for 6 meters

4.6 MHz (USAF MARS) Halfwave Sloper antenna by W1TR

Map of Brazilian prefix call areas

Inches and meters Javascript Wavelength Calculator allow to input a frequency in MHz and calculate wavelenght in several units considering also fractions of wavelenght and the velocity factor. Includes an usefull inch to meter converter

A page dedicated to servicing and building a 10 meter band moxon Antenna

Dealer of digital and analog panel meters Products include portable test equipment, oscilloscopes, recorders and temperature sensing equipment

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.

Complete collection of the four main parts of this excellet research on modelling and designing half wave dipole antennas for 40 meters band, covering all aspects beginning from full wave length antennas, to shortened, loaded and reshaped dipoles

This variation of the basic horizontal, half wavelength flat top dipole has proven to be a simple, effective antenna suitable for both home and portable use.

A multiband Fan Dipole that works on 40 20 15 meters band, making a folded dipole for 7 MHz band and additional element for the 21 MHz and 14 MHz

Second part of the Dovetron Mod for Kenwood TL922A

A 144 to 148 MHz J-pole antenna, optimized for base station use, is presented with detailed construction plans. This slim, omnidirectional, half-wave antenna is fed at the end through a quarter-wave shorted transmission line, drawing inspiration from the classic _Zepp antenna_. The design emphasizes achieving a 1:1 VSWR and good efficiency on the 2m band, noting that even a one-percent error in calculation can significantly impact performance. The article provides specific dimensions in inches for the radiator, quarter-wave section, and feed point, along with a parts list for construction from inexpensive materials, estimated at approximately **$10** total cost. The resource offers practical construction tips covering copper pipe selection, L and T joint variations, and detailed soldering instructions using a propane torch. It addresses feedline attachment, the critical role of a four-turn, _5-inch diameter_ choke to prevent coax radiation, and proper antenna fastening techniques, including grounding for lightning protection. The author explicitly advises against scaling the design for other bands due to potential efficiency loss and offers guidance on corrosion protection. The antenna design has been released into the public domain for private amateur use.

A quad turnstile consists of two cubical quad loops oriented in a diamond configuration and angled 90 degrees apart from one another with both diamonds sharing the same top and bottom points

Have wondered why a Smith chart has such strange grid lines. Believe it or not, there is a logical progression from Speedometers to Smith charts that will make the Smith grid crystal clear.

Measure the AC current flowing through your appliances

Extending The Bandwidth of 80 Meter Dipoles

Six meter club of chicago smcc amateur radiomembers interested in hf/vhf/uhf, special events and public service

The **Arlington Amateur Radio Club** (K5SLD) website details club activities, including a weekly Taco Tuesday net on their 147.140 MHz repeater with a 110.9 Hz PL tone. The club, organized in July 1955 by 22 hams, also hosts monthly dining events and promotes Community Emergency Response Team (CERT) training through the Arlington Fire Department. Membership renewal information for 2026 dues is prominently featured, with an online payment option and a donation button available on the "Pay Dues" page. Club communications extend to a dedicated Facebook page for members and the wider amateur radio community. The site lists upcoming contests and encourages participation in local events. The 2-meter repeater net is open to all, fostering local camaraderie and technical exchange among hams in the Arlington, Texas area, regardless of club affiliation.

This antenna is a vertical loop antenna mounted on a 8 meters high grounded mast with an input impedance of 50 Ohms without a matching device

Windows shareware contest log program for the ARRL 160 meter contest

A Six-element Yagi Beam for 6 Meter by W1JR proiddes a power gain of 10.2 dB over a dipole it is built on a 24 foot long boom

10 meter 28.286 mhz 100 milliwatt Beacon

Experimenting a 20 40 meter short coil loaded dipole antenna with the goal to keep the total length under 40 feet so that the dipole can be mounted on two 20 foot fiberglass pole to make a 20/40 meter rotatable dipole.

6 Meter J-Pole from 450 Ohm Ladder Line a quickie project

50 Mhz page by YT1VP

Sound card based multimeter

A light and sturdy Quad for 10 and 15 meters. Basic Quad antenna design considerations. Building and assembling a dual band HF QUAD antenna, designing and joining cross-arms and boom, assembling spreader and element wire installation notes. QST article.

Producer of meter test equipment for electricity meters testing and calibration

Two receivers compared, Drake R8A and Palstar R30

The RBN S-Meter visualizes real-time HF propagation data from the Reverse Beacon Network (RBN). It processes thousands of automated spots per hour, providing a real-time picture of active RF paths on HF bands. Users can set their vantage point using _Region Mode_ or _Grid Square Mode_. Region Mode allows selection from broad geographic areas like E. North America or Europe, while Grid Square Mode uses a Maidenhead grid square and radius for more precise data. The app displays eight region panels, each with horizontal bars for bands 160m through 6m, indicating signal strength with a color ramp from green to red. A dimmer trail shows peak hold values, and an S-unit readout provides additional detail. The app is a free web application accessible on any device, offering a practical tool for ham radio operators interested in CW, RTTY, and FT8 signals. It features a Progressive Web App installation option for enhanced usability on mobile and desktop platforms. Users can install it on Android, iOS, and Windows devices, providing a native app-like experience. The app replaces the previous Windows standalone executable, incorporating user feedback to improve features like grid square mode and automatic location detection.

Presents the construction of a shortened _Morgain_ dual-band wire antenna for 40 and 80 meters, specifically designed for installations with limited physical space. The design achieves a compact footprint of approximately 10 x 0.5 meters, utilizing 64 meters of 1.5 mm² insulated electrical wire. The article details an alternative configuration that reduces the antenna's physical length while maintaining its electrical characteristics for dual-band operation. Author _Remo - IM0JZJ_ conducted tests from Sant'Antioco, Sardinia, reporting SWR measurements of 1.2:1 to 1.4:1 on 40 meters. On 80 meters, SWR ranged from 1.1:1 to 1.5:1 across 3620 kHz to 3720 kHz, with a 1:1 current balun recommended for coaxial feed due to the antenna's approximately 50-ohm feed-point impedance. The installation used two 11.50-meter galvanized steel poles, supporting the antenna at about 10 meters above ground. Construction involves three wooden boards and sixteen fiberglass laminate spacers, with specific instructions for routing the 32-meter wire arms. The design eliminates jumpers for 40-meter tuning but requires two jumpers approximately 1.45 meters from the ends for 80-meter operation, which are tuned and then permanently soldered.

All the essentials about the Dip Meter or Grid Dip Oscillator used for many RF measurements including detecting resonance, locating RF emissions, and making many RF measurements.

Windows shareware contest log program for the CQ 160 meters contest

A trap antenna dipole covering two differen bands made reusing an old 160/80m inverted vee antenna.

Map of Argentina Locators

Beacon website of WE4S, Grady Donaldson, located in McDonough, GA. EM73TM.

World-Wide 50MHz Beacons database maintanied by G0LGS provide a fully sortable table available also in a google map format

Antenna may be made practically from any wire (strand, solid) having a reasonable diameter 0.5 2.0 mm (24- 12 AWG). Antenna may be installed at any balcony of 3 to 6 meter length.

Constructing a basic multimeter involves integrating a 0-1mA meter movement with various shunts and multipliers, selected via a switch, to create a versatile instrument capable of measuring DC volts, current, and resistance. The design outlines two main units: a primary unit handling six DC current ranges up to 1 amp and eight DC voltage ranges up to 1000 volts, alongside an internal battery for an ohms range up to 200,000 ohms. This approach allows for a practical, hands-on understanding of meter operation. An add-on unit further extends the multimeter's capabilities, incorporating a meter rectifier and switched series resistors to provide four AC voltage ranges up to 100 volts. Additional shunt and series resistors, designated Ra and Rb, are included to expand the instrument's range to 10A and 5kV, demonstrating how modular design can enhance functionality. When this add-on is in use, the main instrument is set to measure 1mA FSD, connecting via specific lugs. Component selection emphasizes precision, with 1% tolerance high stability resistors for series elements and Eureka resistance wire for shunts. The design specifies values calculated for a meter with 60 ohms internal resistance, noting that these would require modification for different meter characteristics. Experimental adjustment of shunt values is recommended to ensure accurate readings against a calibrated reference meter, reinforcing practical calibration techniques.

How fix Astron 70 model number VS-70M amp meter not working

Build a digital AC voltmeter to measure the output range from 0 to 150VAC with reasonable accuracy

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

A 70 MHz Transverter project with a block diagram and schematics

Developing operational amateur radio equipment for the 134 GHz band presents significant technical challenges, particularly in frequency generation and stability. This resource details the construction of a 134 GHz system, outlining its architecture with separate transmit (Tx) and receive (Rx) modules, each employing a local oscillator (LO) and RF head units. The system utilizes a dual Flann 50 GHz lens-type horn antenna configuration for optimal signal coupling. The transmit path incorporates an LMX2541 synthesizer chip operating at approximately 2.8 GHz, referenced by a 10 MHz double-oven Morion OCXO for exceptional stability. This signal is multiplied through a series of stages (X4, then X2) to generate a 22.4 GHz signal, which subsequently drives a dual series diode multiplier to produce the final X6 signal for 134 GHz operation. The receive side features an anti-parallel diode mixer coupled to a 144 MHz transceiver via a preamplifier, ensuring effective downconversion. Operational mode is CW, achieved by keying a multiplier stage. The project includes images of the Tx and Rx head units and describes a successful 3.5 km test with G8ACE, demonstrating stable signal tones due to PLLs locked to OCXOs at both ends, confirming the system's robust performance.