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High power, UHF, L-band, S-band, C-band, microwave frequency amplifier and oscillator devices, pulsed, CW, fixed-tuned, or tunable devices in the range of 600 MHz to 2000 MHz

The Southeastern VHF Society (SVHFS) is a not-for-profit organization incorporated to promote amateur radio operation on the bands above 50 MHz in the southeastern United States.

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.

This article describes the construction of a high performance transmitter and receiver for SSB (voice) communication covering the 14MHz (20 meters) high frequency amateur radio band with output range 15 to 20 watts and a top audio sound quality both on transmit and receive.

A 70 MHz Transverter project with a block diagram and schematics

This DIY vertical multi-band Windom antenna offers a practical and effective solution for amateur radio enthusiasts seeking a versatile and compact antenna for HF communications. Its simplicity of construction, multi-band capability, and favorable performance make it a valuable addition to any radio shack. The article provides detailed instructions on constructing the antenna and balun, along with diagrams and component specifications. Field tests demonstrated successful contacts with stations across Europe and North America on 14, 18, and 28 MHz. The antenna exhibited comparable performance to a W3DZZ dipole and outperformed a Cobweb antenna on 18 MHz. Low noise levels were observed, effectively suppressing background noise.

The antenna described in this article is for 50 MHz, but the design can be scaled for any band, including VHF, UHF, or even the higher HF bands. The antenna is nothing more than a square loop of wire, approximately 30" (or ~76cm) per side. The loop is fed in the middle of one side, and the opposite side to the feed point has a gap in it.

The PI6ATV repeater, operating on 10.475 MHz, serves the amateur television community by providing both analog and digital DVB-S2 services. Recent updates include user-adjustable Symbol Rate settings via Webcontrol, allowing operators to optimize their digital ATV transmissions for various conditions. This functionality, implemented on December 13, 2022, enables dynamic configuration of the digital stream. Significant technical milestones include the return of the analog ATV transmitter on 10.475 MHz, featuring a newly constructed liquid-cooled final amplifier by Edwin PD2EBH. This restoration on September 6, 2020, followed an 18-month hiatus, ensuring continued support for traditional analog ATV enthusiasts. The repeater's transition to DVB-S2 modulation, initiated on December 20, 2018, addressed capacity limitations of the previous DVB-S setup. This change from 20 MS/s with FEC 3/4 to DVB-S2 allowed for more efficient data handling, accommodating multiple channels within the available bandwidth and enhancing the overall digital ATV experience.

A home made magnetic loop for HF Bands. This small and compact loop is designed to support small power transmissions on HF bands, from 7 MHz to 21 MHz

DL1OFC, operating from Hankensbüttel, Germany, shares insights into the fascinating hobby of amateur radio. While the station has been on hiatus since 2016, the site provides a valuable archive of activities and technical information. DL1OFC was active across various bands and modes, including 145.225 MHz FM, 430.225 MHz FM, 29.600 MHz FM, and DMR via DB0AGM on TS-1 TG-262 DL. Shortwave operations included SSB on the 40m through 10m bands, as well as 6m. The site details regional amateur radio activities in and around Hankensbüttel, offering a glimpse into local field days and community involvement. A notable feature is Die Isetalrunde, a regional amateur radio net covering the area from the Harz mountains to the sea. The site also includes general information on radio technology, tips for obtaining an amateur radio license, and discussions on VHF/HF propagation, including specifics on the 70 MHz band.

How to setup and configure the buddipole antenna in the J-Pole mode for the six meter band

A simple portable dipole antenna for the 40 meter band using a total lenght of 18 meter. It can be used for 80 to 10 meters coverage using a antenna tuner.

The Boone Area Radio Klub (BARK) serves Boone County, Iowa, as its local amateur radio club, actively welcoming visitors to its meetings and weekly ARES nets. The club maintains a 2-meter repeater on 146.850/250 MHz with a 114.8 Hz tone and a 440 MHz repeater on 443.9+ MHz, both situated at the Boone County Hospital, with a simplex fallback on 146.550 MHz for the 2-meter net. Additionally, BARK supports the Iowa 160-meter ARES net at 1.972.5 MHz, which operates at 9:30 PM on Sundays, featuring a rotating schedule of net controls including KNØR, KBØMPL, NØISU, KEØQEU, and KBØLPI. BARK conducts bimonthly license testing sessions on the second Saturday of even-numbered months, with specific dates like October 19, 2024, at the Hamboree, requiring a $15 fee and prior FCC Registration Number (FRN) acquisition. The club's activities are well-documented through numerous photo galleries from past Field Days (1998, 1999, 2008, 2010, 2013, 2017, 2018, 2019), JOTA events (2013), and special event stations (2010 B&SVRR&M). Members like KBØMPL (Margot Conard) have contributed educational PowerPoint presentations on topics such as "Fun with Handie Talkies," "HF Propagation," and "Digital Mode - FLDIGI - OLIVIA 8/500 - JT65 HF - BAND PLANS." The club's officers, as of May 2018, include WØFS (Clay Conard) as President, NØISU (Mitch Carroll) as Vice-President, and KBØLPI (Eric Sloan) as Treasurer/Secretary, guiding the club's operations and community engagement.

A multi-band off centre fed dipole, designed to operate on all bands from 40m (7MHz) to 6m (50MHz). Author claims it will operate on 40, 30, 20, 17, 15, 12 and 10m without an ATU (SWR <3:1) plus 6m with an ATU.

The ZS1J/B beacon operates on 28.2025 MHz with 5 Watts output to a half-wave, end-fed vertical antenna, initially installed in 1977 as ZS5VHF near Durban. The 10-meter transmitter is a modified 23-channel CB radio, and the identification keyer uses a diode matrix unit with TTL ICs from the same era. After relocation to Plettenberg Bay in 1993, the beacon has been in continuous service, with additional QRP transmitters later installed for other bands. In 1994, a single-transistor, 80-meter, 0.5-watt QRP transmitter with a half-wave dipole was added on 3586 kHz, followed by a 160-meter, 0.5-watt unit on 1817 kHz. A 30-meter, 0.5-watt transmitter was installed in 1996, operating on 10.124 MHz. In 2002, a 40-meter QRRP beacon on 7029 kHz, with an output of 100 microwatts, achieved DX reports up to 1100 km from ZS6UT in Pretoria. Best DX reports for the 80m and 160m beacons came from 9J2BO.

The MD-2017 is a dual band DMR and Analog handheld transceiver with a frequency range on VHF 136-174 MHz and on UHF 400-480 MHz

Yaesu FT-7800R dual band 2m/440Mhz mobile radio review

King Conversions has extensive experience in amplifier repair and conversion King Conversions specialize in converting HF amplifiers to operate as monoband amps on 50 MHz

Over 150 pages of content are dedicated to maximizing activity on the 6-meter band, often referred to as the _Magic Band_. The resource details various propagation modes, including sporadic E, F2, and tropospheric ducting, providing insights into their characteristics and how to leverage them for DX contacts. It also covers essential equipment considerations, from transceivers and transverters to specific antenna designs optimized for 50 MHz operation, such as Yagis and Moxon antennas. The eBook presents strategies for participating in 6-meter contests and pursuing awards like _VUCC_, offering practical advice on logging software and operating techniques. It includes discussions on software tools useful for predicting propagation and managing contacts, alongside guidance on finding and utilizing DX maps to identify openings. The author, K5ND, shares his extensive experience to help operators achieve successful 6-meter DXing. Specific sections address the code of practice for 50 MHz operations and provide assistance in locating rare DX opportunities. The content is structured to guide both new and experienced operators through the nuances of the band, from initial setup to advanced operating strategies.

This article is about two excellent small helical antennas for the two meters band. With performance close to that of full sized antennas, these small helical antennas are low in profile but high in efficiency.

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

Sound clips and notes on sporadic E on four meter band

The page provides information on a simple 50MHz J-Pole Antenna project based on the DK7ZB design. It explains the principle of the Wireman-J-Pole, the feeding process, practical mounting, and simulation results using MMANA GAL. The content aims to guide amateur radio operators in building their own J-Pole antennas for the 6-meter band.

Antuino is an accurate instrument that can be used in the field to measure SWR, field strength, modulation, etc. In the lab, it can be used to sweep filters, measure gain, distortion, frequency response, etc. It works upto 150 Mhz. On the third harmonic, it is usable on 435 Mhz band as well (with reduced sensitivity).

The TBJ-1 – a triband base antenna was published in March 2017 QST. This antenna covers 2M/220 MHz/70cm in one 6ft 3/4 inch PVC pipe and requires no radials.

Transverter for 13 cm 23 cmd and 33 cmd band. 23 cm RF power amplifier, RF power amplifier for 2.4 GHz for the QO-100 satellite. Popular for the 1296 MHz transverter

The Baofeng UV-5R handheld transceiver, introduced around 2012, operates across the 2-meter (144-148 MHz) and 70-centimeter (420-450 MHz) amateur bands, offering dual-band receive and transmit capabilities. This review provides an early assessment of the radio's form factor, user interface, and general performance, noting its compact size and the inclusion of a **VFO/Memory mode** button for frequency management. The device supports both FM and narrow FM modes, with a reported power output of 4 watts on VHF and 3 watts on UHF, making it suitable for local simplex and repeater operations. Key features discussed include its 128-channel memory capacity, a built-in VOX function, and a **DTMF keypad** for tone dialing and repeater access. The review highlights the radio's ability to scan frequencies and memories, along with a dual-watch function allowing simultaneous monitoring of two frequencies. Battery life is addressed, with the standard 1800 mAh Li-ion pack providing several hours of operation depending on transmit usage. Initial impressions cover the radio's construction and the clarity of its LCD display, which shows both A and B band frequencies.

This is a project aboout compact and portable a QRP antenna tuner for use in the HF ham radio bands from 3-30 MHz, even if it's a compact and efficient project this small antenna tuner will not match any possible load.

A not-for-profit organization incorporated to promote ham radio operation on the bands above 50 MHz in the southeastern United States.

Gimme Five reloaded, a compact 5 band QRP SSB transceiver in SMD technology. This unit covers 5 bands within the amateur radio spectrum (3.5, 7, 14, 21 and 28 MHz). Receiver is a single conversion unit with an interfrequency of 9 MHz. Transmitter uses 5 stages and has got a power level of 10 watts PEP output.

List of countries that have been worked from the Czech Republic on 50 MHz band since January 1, 1993

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

Two beacons in 3 and 1.2 cm band, 10368.755 MHz and 24048.870 MHz

A homemade delta loop antenna for six meters band in German

Stacking yagi antennas for 50 Mhz band article by by Zaba, OH1ZAA/NN0Y

A homemade j-pole antenna for six meters band, designed to work on local repeaters, and working on the 52-53 MHz. Includes a list of needed materials and detailed description on assembling the copper tubes used to build this antenna.

This antenna is a classical antenna working on 7,10,14,18,50 MHz is implemented with three traps for 30, 17 and 6 meters

Top Loaded Vertical Antenna 3,5 MHz 80m and a 14 MHz Trap for the 20m band. The weight of this portable vertical antenna is less than 1 kg, including the ground network. The weight of the telescopic fiberglass fishing rod is another 1kg. The rod expands from 1.5 meters to 8 meters.

CB station AP from Lieksa Finland

Allocation of 4 meter band worldwide

Presents amateur radio activities and experiences from JJ0LUU and JJ0LXF, two operators based in Japan. The weblog, hosted on shinshu.fm, documents their on-air operations, equipment setups, and general ham radio interests. Content often includes details about specific contacts, antenna configurations, and local operating conditions within the Japanese amateur radio community. The resource primarily focuses on personal operating logs and occasional technical discussions relevant to their station. It offers a glimpse into the daily life and pursuits of Japanese **amateur radio** operators, detailing their engagement with various bands and modes. JJ0LUU and JJ0LXF share their passion for radio communication, contributing to the broader online repository of individual ham radio narratives. The site serves as a digital logbook and informal platform for sharing their **DXing** and contesting endeavors.

The XV4-10 is a linear transverter for the 4m band to be used with a 10m transceiver. Input frequency 29-30 MHz, output frequency 69.5-70.5 MHz

Homemade receiver for 80 meters band. The receiver works very well (in fact better than some of its successors), especially the AGC makes listening to 80m QSOs a real pleasure. Sensitivity is not cutting-edge, but on a full-size short-wave antenna it is by fare sensitive enough.

AC7GZ/B is a converted Sharp CB-2460 Citizens Band transceiver operatin on 28.2118 MHz.

An Hentenna project for the six meters band. The standard size of standard hentenna is width 1/6 wavelength x height 1/2. The antenna build in this project is a full wavelenght antenna for the 50 MHz providing a 6.8 dbi gain.

DF0WD/DL4YHF's Longwave Overview details amateur radio operations on the 135.7 to 137.8 kHz segment in Germany. The author outlines the "inofficial" European band plan, specifying segments for QRSS, TX tests, beacons, conventional CW, and data modes. Early LF activities at DF0WD began with a 20-watt CW transmitter, later upgraded to a homemade linear transverter capable of 100 watts, driven by an Icom IC706 on 10.137 MHz. The station's antenna system includes a 200-meter wire, approximately 10 meters above ground, supported by football field light-masts. Despite its length, the antenna's efficiency is noted as very low due to the immense wavelength of about 2.2 km. The author's experience highlights the significant challenge of achieving effective radiated power (EIRP) on LF, estimating DF0WD's EIRP at around 80 milliwatts based on field strength measurements from PA0SE. DF0WD/DL4YHF has successfully worked numerous countries on 136 kHz CW, including DL, F, G, GI, GM, GU, GW, HB9, HB0, LX, OE, OH, OK, OM, ON, OZ, PA, and SM. The author also mentions ongoing efforts to log contacts with CT, EI, LA/LG, and to complete a two-way QSO with Italy, demonstrating persistent activity on this challenging band.

The purpose of this construction is to enable the realization of an HF antenna called W3DZZ with minimal equipment and low cost. It allows traffic on the bands 3.5 / 7/14/21 and 28MHz.

The DIY 137 MHz WX SAT V-dipole antenna project details the construction of a specialized antenna for receiving weather satellite transmissions. It provides specific dimensions for the dipole elements, designed for optimal reception around the 137 MHz band, which is commonly used by NOAA and Meteor weather satellites. The resource outlines the materials required, such as aluminum tubing for elements and PVC for the support structure, along with the necessary coaxial cable and connectors. The article presents a clear, step-by-step assembly process, including how to form the V-shape and connect the feedline. It emphasizes practical considerations for mounting and weatherproofing the antenna for outdoor deployment. The design focuses on simplicity and effectiveness for amateur radio operators interested in satellite imagery. Key aspects include the precise angle of the V-dipole and the lengths of the radiating elements, which are critical for achieving the desired circular polarization response for satellite signals. The resource includes photographic documentation of the construction phases and the final mounted antenna.

A review of the Yaesu FT-8900r 29/50/144/430 MHz FM Transceiver, providing 50 Watts of power output on the 29/50/144 MHz Amateur bands, and 35 Watts on the 430 MHz band.

An introduction to NPR by Daniel Estevez. In this blog article Daniel EA4GPZ / M0HXM, introduce the new IP communication protocol over the 70 cm amateur radio band. Daniel is an experienced operator on IP on 430 MHz with CC1101 and Beaglebone black project and makes a good comparison of the two projects.