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The QM7 antenna is a simple 7 elements Yagi with 3.7 m boom length for the lower 144 MHz SSB/MGM band, in PDF Format

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

Yagi beam plans for 144MHz band

A 144 MHz kilowatt amplifier project details the construction and performance of a high-power VHF linear using the GU74b tetrode. This Russian tube, equivalent to the Svetlana 4CX800, is noted for its conservative datasheet ratings, performing closer to 800-1000W anode dissipation in practical applications. The design prioritizes compactness and achieves 1.2 kW output with only 20W of drive power, demonstrating a 70% efficiency at 2.5 kV plate voltage. The amplifier has been successfully deployed in demanding _EME_ (Earth-Moon-Earth) operations since June 1994. Challenges encountered during development included achieving stability with a grid-1 input configuration. The author, _CT1DMK_, opted not to publish the full design due to its complexity, suggesting it might be difficult for less experienced builders to replicate successfully. However, he invites direct contact for those with specific interest in the design. Future plans include a "144MHz GS35b compact amplifier" project, promising another kilowatt-plus design. This resource offers insights into high-power VHF amplifier construction and the practical application of specific power tubes.

A full wave 2-meter VHF omnidirectional antenna by ON6MU

A project by N6BG for a four element cubical quad antenna for the 2 meters band

A homebrew project for a 2 meter 4 element yagi beam antenna by 2E0HTS

A preamplifier project based on Rainer DJ9BV project, in french

144 and 432 Mhz GS35b High Power Amplifier

Yagi Calculator is a free Windows program that also runs well on Linux, Ubuntu 8.10 under Wine, to produce dimensions for a DL6WU style long Yagi antenna. Long yagis are commonly used from the 144MHz amateur band to the 2.4GHz band.

This article describes the 144MHz horizontally polarised antenna at VK1OD in November 2008. The antenna uses two identical four element arrays that were constructed around 1970

Over two decades of historical DX spots and news are archived on this Japanese resource, providing a retrospective look at amateur radio propagation and activity across various bands. The content is organized chronologically, with separate sections for _50MHz_, _HF DX_, _144MHz_, _EME_, and Satellite clusters, detailing spot data from as early as 1996 through 2014. This extensive archive serves as a valuable historical record for analyzing long-term propagation trends and significant DXpeditions from a Japanese perspective, offering insights into band openings and rare entity activations. The resource also includes links to other DX news sites like _425 DX News_ and _Ohio/Penn DX Bulletin_, along with QSL manager lookups and callbook services, enhancing its utility as a comprehensive DX information hub. While the primary cluster data is historical, the compilation of external links points to active resources for current DX operations. This makes it a useful reference for contesters and DXers researching past conditions or seeking information on specific DX entities and their QSL routes.

Design for a 5 element 2 Metre beam with a forward gain of 8dBD and a front to back ratio of over 24dB.

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

G0KYA Moxon antenna for 2 meters band

Dedicated to 50MHz and 144MHz. Online 2m and 6m logs. Real Audio sound clips of Tropo, Aurora, Sporadic E, Meteor Scatter, TEP and F2 Propagation.

Construction of attenuator, suitable for fox hunts at 144mhz

Linear Amp UK specializes in the design and production of high-quality linear amplifiers, offering models for HF, VHF, and UHF amateur and commercial applications. The company emphasizes nearly 30 years of experience in crafting each unit, ensuring robust performance and longevity. Their product line includes amplifiers engineered for a 100% duty cycle, promoting continuous and reliable operation across various modes. The amplifiers feature solid, dependable designs, ensuring quiet and effortless performance during transmission. Each unit is hand-built to stringent standards, reflecting a commitment to durability and operational stability. All products are CE approved, confirming compliance with European safety and environmental directives, and come with a standard two-year warranty, providing assurance to operators. Key specifications often include coverage for 1.8-30MHz (WARC bands), 50MHz, 70MHz, and 144MHz, utilizing tubes such as 811, 572, 811A, 572B, GS35, GS35B, 8877, 3CX1500, and _3CX1500A7_ in their designs.

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

A simple accessory for a satellite station, that allows using a 6 meter capable radio in conjunction with a typical S-band to 2 meter converter

Automatic 144MHz E-skip Alerts for North America

A 144MHz FM class C RF Power Amplifier based on a 2N6084 RF transistor, that can produce 50w output max

Solving interference from television channel 11 on 144MHz transverters by Chris Cox, NØUK, G4JEC

A 3CX1500/A7 8877 144mhz W6PO amplifier, that running a little over 4kv on the plate, this Amp will do over 2kw out.

These pages containing informations about contesting on 144MHz and higher bands. All informations are only in Czech language.

A home made, dirty and quick moxon antenna for 144 MHz made with PVC pipes.

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.

144MHz 2m Portable Yagi VHF Beam Antenna. This page contains construction details on a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

A home made project for a 7 element yagi antenna for the two meters band based on the DK7ZB original desing.

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

Learn how to build a VHF 144MHz transverter connected to an LMR SDR radio using easily accessible components. The transverter works by mixing the 144Mhz input frequency with a 116 MHz local oscillator frequency. Explore the challenges of finding a 116 MHz crystal and the solution of using a programmable Si5351A oscillator. Follow the provided schematic for the RX and TX sections. The transverter design is still a work in progress, with ongoing trials to achieve optimal results.