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HamAlyzer is a spectrum analyzer made just for hams, save plot images easily for emailing, monogramed with your call sign. HamAlyzer looks no more supported, here 2.8 trial version available. Download hamalyzer

Hexagonal Wire Beams for 40-10m from DL7IO, different mono/multiband designs with building descriptions and model files for EZNEC

20m T-Monopole short vertical antenna for 20 meters by AA5TB

A free computer aided design program to help users without special expertise in filter design to create filters using Linear Technology's monolithic filter ICs. With FilterCAD, you can design lowpass, highpass, bandpass and notch filters

A 3 Element Mono-band Yagi for 20 meters by Kees Wiegers, PA5CW (ex-PA3BHS)

Catalogs a diverse array of Software Defined Radio (SDR) projects and realizations, systematically classified by their sampling methodologies and underlying hardware architectures. The resource delineates projects into categories such as those utilizing soundcard sampling of traditional transceiver audio outputs (Type Ia), mono soundcard sampling of intermediate frequencies (Type R1x-x-xx), stereo soundcard sampling of I/Q IFs (Type Q1x-x-xx), dedicated stereo audio ADC sampling of I/Q IFs (Type Q2x-x-xx), direct antenna RF signal sampling with off-the-shelf acquisition boards (Type R3x-x-xx), dedicated RF ADC sampling of analog IFs (Type R2x-x-xx), dedicated RF ADC sampling of direct antenna RF signals with ASIC-based processing (Type R4x-A-xx), FPGA-based processing (Type R4x-F-xx), and specialized IF chipsets combining ADC and DDC functions (Type Dxx-S-xx). Each entry provides a brief description, often including pricing, availability of source code, and specific hardware components like ADCs, DACs, DDS, and FPGAs. The compilation presents various practical applications, from PSK31 and Packet radio implementations to adaptations of the DRM standard for amateur radio bandwidths, such as Hamdream and WinDRM. It features specific hardware designs like the SoftRock-40 for the 40-meter band, the Firefly SDR for 30m and 40m, and more complex systems like the Quicksilver QS1R, which employs a 16-bit 130 Msamples/s ADC and an Altera Cyclone III FPGA. The resource also lists sample processing software, RF front-end designs, and academic/commercial SDR initiatives, offering insights into different approaches for I/Q conversion and digital signal processing in SDR systems.

Build a Multi-Band Mono Delta Loop for 40, 30, 20 and 15 Meters.

17 Meter 3 element TA33 junior mono band yagi antenna conversion project by K6TC

A **90-foot tall** top-loaded vertical antenna for the 160-meter band is detailed, constructed from aluminum irrigation tubing. The design incorporates four sets of four guy wires for structural stability, essential for an antenna of this physical size. This _monoband_ vertical is optimized for low-band operation, providing a robust solution for DXing and contesting on 1.8 MHz. The document includes specific construction methods for assembling the aluminum irrigation tubing sections and securing the guy wires. While a full NEC model is not explicitly provided, the physical dimensions and construction materials are sufficient for replication by experienced builders. The antenna's height and top-loading configuration are critical for achieving efficient radiation on 160 meters, particularly in minimizing ground losses.

Picture and construction details of a 5 element 20 meter monobander

The Cedevita-20 is a hybrid monoband antenna, the result of merging the radiator of a shortened vertical with one element of a dipole. It fits on most balconies and must be hung from the ceiling. By ik1zyw Paolo Cravero

A 5 elements yagi antenna for 10 meters band project, plane and picture of the EF105A by YU7EF

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.

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.

Lincomatic's Homebrew WiFi Antennae, Cantenna, Toothpick Monopole, Patch Antenna, BiQuad, collinear wifi antenna all in one page

The basic antenna is a vertical monopole, using elevated radials to complete the ground plane by k5oe

A delta loop antenna project for the 40 meters band, include dimensions 80 meters band, with construction details, schematic and tuning instructions

A vertical monoband that's small, light and portable, needs no counterpoise and performs as well as a home antenna

Includes EH antennas, 7Mhz vertical monopoles, 5 elements vee log-yagi for 10m and more

A 3 element yagi antenna for 17 meters

A simple to build Yagi 2 element antenna for 15 or 20 meters band by 9m2mso

A potpourri of 160-Meter vertical antennas and modeling issues, inverted-L, 3-element parasitic array, 1/4-wavelength monopole

An homebrew project for a 3 elements yagi monoband antenna for the 20 meters by 9M2MSO

OE1MWW monopole antenna made with common RG 58 or RG 213 coaxial cable

If you are looking for an easy antenna for your favorite band, you can't go wrong with an halfwavelenght dipole, all you need is 3 insulators and some wire

Sound samples of the transmission modes recorded at 11025 samples per second, mono and the message in all of the samples is the same: "the quick brown fox jumps over the lazy dog 1234567890".

Wideband VHF/UHF/SHF monolithic PreAmp based on MARx-series by ON6MU

A 7 elements yagi beam monoband antenna for 14 Mhz by VE3GK

Located in France, DXBeam designs and manufactures a range of monoband, dual band and triband antennas, rotary dipoles, Moxons and Yagis

A monoband yagi for 14 MHz a PDF article from 73 amateur radio magazine by AB4GX

Outlines recommended operating procedures for amateur radio repeaters, detailing best practices for general on-air conduct. It emphasizes using simplex when possible, monitoring the frequency before transmitting, and maintaining concise, thoughtful transmissions to avoid monopolizing the repeater. The resource also stresses the importance of legal identification, such as the Canadian requirement at the beginning and end of a contact and every thirty minutes of operation. Furthermore, the article provides specific instructions for **autopatch** operation, including access codes and the necessity of brief calls, while cautioning against misuse for long-distance calls or commercial purposes. It highlights the financial support expected from regular users to maintain repeater infrastructure. Finally, the guide differentiates between permanently linked repeaters, which offer extended coverage, and **code access linked repeaters**, explaining the sequence of identification and code entry required to establish and terminate links for broader communication.

AB4GX K4EAA Mononband yagi antenna for 20 Meters

A 10 Bands mobile antenna for about the price of 2 mobile monobanders.

Multiband and monoband HF Vertical antennas and rotatable dipoles manufacturer based in Texas USA

Demonstrates the construction of two distinct wideband RF preamplifiers, detailing their component requirements and performance characteristics. The first design leverages monolithic microwave integrated circuits (MMICs) such as the MAR-6, MAR-8, or PGA103, offering a broad frequency response from DC to 2 GHz with a gain of 22.5 dB at 100 MHz and a noise figure typically below 3 dB. This MMIC-based amplifier incorporates protection against power supply transients and features a 50 Ohm input/output impedance, operating from an 8-20 volt supply with low current drain. The second preamplifier design utilizes a BSX-20 transistor, providing amplification across the 14 MHz to 550 MHz range. This simpler, more economical build achieves an average gain of 12 dB at 145 MHz and a noise figure of approximately 1.1 dB. It operates from a 7-15 volt battery supply with a current draw of 6 mA. Both projects emphasize critical construction techniques, such as maintaining short RF connections, ensuring 50 Ohm impedance paths, and mounting the circuit within a shielded enclosure to optimize performance and minimize noise. The resource also discusses phantom power options for antenna-mounted preamplifiers and precautions for use with transceivers, including output protection diodes and static bleeders.

A monoband end-fed half wave for 10m, 20m or any other HF band, includes a PDF with detailed information to build your own monoband or multiband antenna

This project will enable you to build a monoband long wire inverted vee with 3/4 wave length sides that will have a bit of gain

Dutch Antenna and Tower Manufacturers from Slimline Square Triangular Round Towers. Antennas production include Yagi Monoband/Dipole/HF Quad /50MHz and 70MHz Yagi-Quad, VHF-UHF yagi-Quad and Comby antennas VHF/UHF/SHF

A monoband antenna with large bandwidth in French

A 11 pages pdf file about monoband or multiband end fed half wave vertical antenna that is great for DX and very cheap to build by Steve G0KYA

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

A monoband J pole antenna dimensions sheet by N6JSX

EF155A1 21 MHz monobander antenna by YU7EF

A vertical monoband antenna design that can work from 6 meters to 70 cm by F5ZV in French

Unlocking the full multiband potential of the 225 Ohm elementary radiator in a folded monopole, dipole-like or turnstile layout, by Francesco Errante

A simple and awesome wire monoband antenna, very usefull for portable and dxpeditions usage, consist of two elements, a driver and the reflector. This endfed halfwave gives a very low take off angle and is very suited for chasing DX.

This project details the construction of a **full-sized 40-meter vertical antenna**, born from a renewed interest in 7 MHz operation and a desire for improved effectiveness over simple dipoles. The author, K5DKZ, initially focused on VHF experimentation, which provided an inventory of aluminum tubing and fiberglass spreaders for this endeavor. Before this vertical, K5DKZ utilized an 80/40 meter inverted-vee trap dipole and a 40-meter broadband dipole, but now primarily uses a pair of full-sized, phased, quarter-wave verticals spaced 35 feet apart for serious 40-meter work. The construction involves a base-heavy design for stability, using a 44.5-inch section of 1-1/4 inch steel TV mast driven into 1-3/8 inch aluminum tubing, insulated by a 105-inch section of Schedule 40 PVC pipe. The assembly reaches 31 feet, close to the 32 feet required for a quarter-wavelength on 40 meters, with fine-tuning achieved by winding wire onto a fiberglass spreader. The design is explicitly presented as a foundation for a two-element 40-meter Yagi beam, outlining modifications like substituting aluminum for steel in the base and using an inductive hairpin match for the driven element. The article also discusses tuning considerations for a large 40-meter beam, noting the 100 to 200 kHz upward frequency shift when raised, and suggesting methods for installation on a tower. The author emphasizes the cost-effectiveness and good performance of the monopole approach, especially when multiple verticals are needed.

An efficient monoband end-fed half wave for 10m, 20m or any other HF band

An interesting article on loading short vertical monopole antennas, representing six different methods. Base loading, Center Loading, Top Loading, Continuous loading, half and half loading and capacitive top loading.

A comprehensive listing of AM Stereo radio stations in North America with listening tips, news, AM mono to stereo radio conversion information, sources of AM Stereo receivers and a history of AM Stereo broadcasting.