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Homebrew VHF Yagi 50MHz 144MHz 432MHz 1296MHz 2320MHz 6M 2M 70CM 23CM 13CM Yagis

How to build a 432 Mhz Quagi, using a wood-made boom, and gives a 13 DBI Gain

U6YRN 6 element yagi antenna for 430-450 Mhz

432 MHz EME low noise amplifier. Circuit, components and image by Christoph Petermann DF9CY

The latest and best yagi beams for 432MHz tested and optimized with NEC

DF9CY - 10 Element for 432 MHz Winkler Antennen

A 14 elemets yagi antenna for 432 MHz based on DK7ZB design

144 and 432 Mhz GS35b High Power Amplifier

A full duplex antenna system for 144 432 Mhz

OZ2OE Technical Home Page - 432 MHz PA with 8874

Demonstrates the design and construction of a 9-element Yagi antenna for the **70 cm band** (432 MHz), based on the DK7ZB concept. The resource details EZNEC+ calculations for a single antenna, providing gain, sidelobe suppression, and front-to-back ratio figures. It also presents a comprehensive analysis of stacking two such antennas, including optimal stacking distance (1000 mm) and the resulting performance enhancements for the stacked array, such as an increased gain of 17.03 dBi. The article includes detailed drawings, wire file dimensions in millimeters, and azimuth/elevation plots for both single and stacked configurations. Practical construction steps are documented with original photographs, illustrating element mounting, the **28 Ohm matching system** using two quarter-wave 75 Ohm transmission lines, and the critical N-connector wiring. It also covers the iterative process of fine-tuning the driven element length to achieve a return loss of 20 dB, validating the EZNEC+ simulation results with actual measurements.

Comparison of several UHF antennas by DF9CY

A short good performing antenna for 70cm

A Quagi antenna project with pictures and dimensions for a UHF Quagi antenna

Receiver converter that can be plugged to the backside of the Yaesu FT-817 battery powered portable transceiver

VHF UHF diplexer by G8MNY

Presents a curated collection of newsletters dedicated to _Earth-Moon-Earth_ (EME) communications, primarily focusing on the 432 MHz band and higher microwave frequencies. The resource details various EME DX experiences and news contributions from operators like K2UYH (W6/PA0ZN), offering insights into successful moonbounce contacts and operational strategies. It serves as an archive of specialized content for those engaged in or interested in extreme weak-signal propagation via the moon. The newsletters provide practical information on achieving EME contacts, often including details on station setups, antenna arrays, and signal reports from challenging DX. For instance, operators might report achieving contacts over **750,000 km** round trip, demonstrating the feasibility of long-distance communication on UHF and microwave bands. The content differentiates itself by concentrating on the unique technical and operational aspects of EME, which contrasts significantly with terrestrial DXing, providing a specialized knowledge base for advanced amateur radio operators.

ATV 432 MHz AM transmitter schematic

This web article by VK3BLG details the construction of an experimental 70cm (432 MHz) circularly polarized patch antenna, intended for satellite communication. The resource provides dimensions, feed point specifications, and impedance matching considerations for a single patch element, with discussion extending to array configurations for circular polarization. Construction involves a copper patch element on a dielectric substrate, fed via a coaxial cable. The design is based on information derived from AO-40 satellite antenna specifications, focusing on achieving circular polarization for satellite reception. The article includes specific dimensions for the patch and feed points, along with impedance values. Validation is implied through on-air satellite reception reports, with initial signal reports of **1 S-point above noise** for AO-40 beacons using a grid reflector, improving to **3-4 S-points above noise** with a 2-turn helical feed. The author references a _NanoVNA_ for impedance measurements and discusses the relationship between slot and dipole antennas in the context of patch design. DXZone Focus: Web Article | 70cm Patch Antenna | On-Air Satellite Reception | Circular Polarization

An easy to build with a cheap HEMT FET Transistor Low noise preamplifier with FHX35LG based on JH0WJF design

5 Element Yagi with Conventional Driver, this little Yagi has a high F/B, which makes it quite useful as a contest stack.

A combined 144MHz Low-Pass and 432 MHz Notch Filter by VE2ZAZ

ZL1BJQ 23 feet diameter dish antenna for 432 Mhz

Message list about 903 Mhz. and above bands. Use various VHF reflectors for the 432 and lower bands. Most traffic will be about 2304 and above.

A 70 cm yagi designed for EME + SSB narrow bandwidth version, strictly G/T breeding. This little Yagi has a high F/B, which makes it quite useful as a contest stack

This walkie is sold without the wide band receiver enabled, this is, only 144 and 432 MHz band

Six meters is a great band for home built Yagis. The elements are reasonably small, but not so small that building tolerances are critical. With careful construction and detailed instructions, it is certainly feasible to build no-tune Yagis up to 432 MHz.

Combined 432 MHz High-Pass - 144 MHz Notch Filter By Bertrand Zauhar, VE2ZAZ

A compact Yagi with bent Driven Element. Worlds smallest yagi that did EME QSO

Comparison of some popular 432 MHz EME antennas by DF9CY

The _DL4EBY_ resource page provides operational data for Earth-Moon-Earth (EME) communications on VHF, UHF, and microwave bands. It includes a 432 MHz and above EME Directory in ASCII and HTML formats. _K1RQG_ provides 432 MHz and up EME Net Notes. EME Operating Procedures were confirmed at the EME Conference 2002 in Prague. A lunar calendar from _DL7APV_ is linked via _G4CCH_'s pages. Resources for CW contest operation include the _PED411i.zip_ file. A "Cheat Sheet 432 & up" is available for EME operations. The _Dubus_ 70cm CW EME Activity Event is referenced for moonbounce activity. DXZone Focus: Operating Activity | Global | EME, CW | VHF, UHF, Microwave

A high G/T Yagi with bent DE for compact contest arrays

Get involved with 70cm Earth Moon Earth communications it is easier than you think, EME promotional Flier

The purpose of this article is to provide radio amateurs with enough background information to understand the technical challenges involved in small-station digital EME on the 144 and 432 MHz bands.

A 3.2m EME dish project that provides a better performance on 1296 MHz (10+dB sun noise vs. 6dB with my 432 array) and an even better performance on 2304 MHz

The prototype for this amplifier was originally designed for 70cm and was used on the 2004 3B9C Dx-pedition to Rodriguez Island for satellite and EME. It had a noise figure of 0.49dB with an associated gain of 20dB.

UHF beacon from JN55VF italy 432,469.0 MHz

Helix antenna 432/435 MHz 14 turns. This 50 ohm impedance antenna allows, when fed with 25/50W of SSB RF, to join the orbiting satellites like AO-40 and AO-10 very easily

The CQ Contest & DX Group, main activities is - participating in contests. Mainly in the Nordic Activity Contest at the 50 MHz, 144 MHz and 432 MHz, though the group holds a full licence, have we not participated in a HF contest yet.

A 18 elements Yagi antenna for 432/435 MHz as published on 2011 CQ VHF magazine

A very small receiver converter that can be plugged to the backside of the battery powered portable transceiver FT817 from Yaesu. A high performance receiver for 2.3GHz amateur radio signal

This article provides a detailed guide on how to build a no holes roof mount for ham radio antennas. The author shares their design that can hold 2 masts and offers tips on installation. The mount is versatile and can handle small 144 Mhz or 432 Mhz beams, as well as small verticals. With adjustable angles and spacing, the mount can be customized to fit different roof types. Additionally, the author suggests affordable options for obtaining Dish antenna mounts. Overall, this DIY project offers a cost-effective solution for ham radio operators looking to mount antennas on their roofs.

This page details my building of a 100 Watt Power Amplifier for the 432 MHz Band based on two Motorola MRF646 transistors taking inspiration by Carlo Gnaccarini VK3PY, formerly VK3BRZ

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.

Manufacturer of 50MHz, 70MHz, 144MHz, 222MHz, 432MHz, 900MHz or 1.2GHz transverters and VHF UHF amplifiers

Antenna project for a home made quagi antenna for UHF Bands, 432 MHz. This projects is done using some aluminium bar rods and includes design and pictures of the project

This resource provides an in-depth look at Earth-Moon-Earth (EME) operating techniques specifically for the 432 MHz band and above. It outlines the differences in operational procedures between the 144 MHz and 432 MHz bands, emphasizing the importance of sequence lengths and scheduling. The initial calling period typically starts on the hour, with the eastern-most station calling first, which is crucial for effective communication. The document also discusses the challenges faced by operators, such as signal readability and the necessity of confirming exchanges. It highlights the significance of using a standardized procedure to enhance the likelihood of successful contacts. Additionally, it covers the use of signal reports and the importance of patience and clarity in communication, especially when dealing with weak signals. Overall, this guide serves as a valuable resource for amateur radio operators interested in improving their EME operations.

The project aims to create a remote control system for the VK5RSE beacons located near Millicent, South Australia. The beacons on 144.550, 432.550, and 1296.550 MHz can interfere with nearby amateur radio operations, particularly for EME work on 1296 MHz. The remote control system uses a DTMF decoder and PIC microcontroller to allow turning the beacons on and off individually or in combination. The system is housed in a diecast box and powered from 5-8V. The password-protected control allows authorized users to manage the beacon operations remotely, helping mitigate interference issues for local amateurs.