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The Yaesu FNB-78 Battery plugs into the FT-897/D. It produces 13.2 VDC at 4500 mAh. The radio can hold one or two and one can be in use while the other is charging.

If you can't get on the air from home, the Internet may provide the answer. By Brad Wyatt, K6WR. Pdf File.

a neat 1:1 50 ohm balun for use on HF horizontal wire dipoles.

Members only techical pages about Sloper antennas

A model of a Guanella 1:1 VHF choke balun using a FT140-61 core

The purpose of this page is to capture and document the Yaesu FT-101 series radios during the 1970's

Catalogs over 9,300 radio transmissions heard within Finland, providing a detailed frequency database for Finnish radio enthusiasts. The resource lists frequencies for various services, including maritime VHF channel 16 at **156.800 MHz**, RHA68 channel 16 at 71.100 MHz, and _MIL AIR_ frequencies like 251.100 MHz. It also documents air traffic control frequencies, such as 123.775 MHz for Area Control and 127.000 MHz for Approach Control, alongside frequencies for Finnish Air Force operations at 140.550 MHz. The database includes entries for commercial shared channels at 170.450 MHz and 458.250 MHz, as well as specific local business frequencies like 443.125 MHz for Sale Merimasku. Shortwave broadcast entries are also present, noting stations like BBC at 6.035 MHz from Tashkent and AIR Akashvani Ext.Sce at 11.900 MHz from Bangalore. The site organizes its extensive listings by categories such as "Liikenne" (Traffic) with 2397 entries, "Radioamatoori" (Amateur Radio) with 781 entries, and "Yle" (General) with 2305 entries. The database was last updated on 26.2.2024, reflecting ongoing maintenance and additions to its comprehensive collection of Finnish radio spectrum data.

I4FAF etrode Tube Linear Amplifier experience

ON6MU Optimized 10 and 6 and 4 element UHF Yagi Antenna

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

JT65A frequencies. List of common HF frequencies where you can work JT65A.

A javascipt online calculator for 2 and 3 element beam antennas. Just input frequency and will diplay element dimensions and spacing. Measurements in Feet and Meters by G4VWL

A listing of 2m SSB nets around the US.

ON6MU optimized 6/9 element vhf yagui antenna with antenna schematic plan and pictures of homebrewed samples.

Comparison chart between Cushcraft R8, Hy-Gain AV640 , Butternut HF6V, Gap Titan and Eco 7+

An RF power amplifier, providing 7 Watts output in HF bands, schematic by ON6MU

How to create a simple but effective half wave dipole, illustrated instrucions on how to build wire antennas

A moxon antenna for UHF in french

Electronic circuit and components layout fot this VHF Preamp

A portable dualband dipole robust and compact antenna usable for horizontal and vertical polarisation by ON6MU

A project of VHF regenerative receiver by VK2ZAY

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

Video construction of a multiband HF trapped dipole antenna based on a variation of the classic W3DZZ design

A novel approach to aerial evaluation with diagrams and graphs by G3CWI

2 meters band VHF dipole with gamma match system

Article on the HF dual band antenna with construction details and how to add 160 meters to the HF2V

Notes on homebrewing antennas by Chris G4CYA, from gamma matching, to phasing antennas, splitters and combiners, baluns and measuring techniques.

A 40 ft vertical dipole antenna that can cover HF Bands from 80 to 10 meters winding a dipole in a 12m HD telescoping fiberglass pole

The MCP-F6/F7 software facilitates memory channel and menu data creation for the Kenwood TH-F6A, TH-F7A, and TH-F7E transceivers. It operates on _Windows_ XP (SP3+), Vista (SP2+), Windows 7 (RTM+), Windows 8 (RTM+), Windows 8.1 (RTM+), Windows 10, and Windows 11. System requirements include a CPU faster than the OS recommendation, RAM exceeding the OS recommendation, and **2 MB** of free hard drive space. Display resolution must be XGA (1024 x 768) or higher. Connectivity to the transceiver requires an optional PG-4Y (RS-232) or KPG-22U (USB 2.0) programming cable. The KPG-22U cable necessitates a virtual COM port driver installation. The software supports COM1 through COM20 for RS-232 communication. Installation requires administrator privileges and involves executing "setup.exe" from the extracted MFX101.zip archive. Uninstallation is performed via the Control Panel's "Uninstall a program" function or by re-executing "setup.exe." Created data files are not removed during uninstallation and require manual deletion. The software version is **1.01**. DXZone Focus: Kenwood TH-F6 F7 | Memory Management | Windows | RS-232

A base station antenna you can easily build for 146,220 or 440 MHz, with performance similar to a J-pole but smaller and less obstrusive

Members only articles on HF mobile antennas, includes an interesting RV antenna with a 5 bands coverage, and another similar antenna for camper.

Schematic and pictures of a W7IUV preamplifier

A full line of single-channel synthesized and crystal controlled vhf and uhf fm receivers. Great for repeaters, telemetry, and control applications.

Homebrew a vertical antenna for 40 and 80 meters band based on popular HF2V model by DL7JV

This Magnetic Longwire Balun (MLB) makes it possible to efficiently use a coaxial lead-in cable with all forms of longwires, T-forms or other types of wire antennas, without the need for an antenna tuner.

Interconnecting the YAesu FT-897 or 897D

HF power amplifier project by YB0AH

This page includes fatures, specifications options and photos of the ICOM IC-746

The Discovery series of amplifiers are designed and built in the UK by Linear Amp UK Ltd, one of the world's leading amplifier manufacturers, specializing in high power RF tube amplifiers. The amplifiers use large GS31 or GS35 ceramic triode tubes. Band coverage 6m, 2m and 70 cms

The RigPix database entry provides a comprehensive technical overview of the Icom IC-746 amateur HF/VHF transceiver, detailing its operational parameters and physical characteristics. It specifies the transmit frequency ranges across 10-160 meters plus WARC bands, 50-54 MHz, and 144-146/148 MHz, alongside receive coverage from 0.03-60 MHz and 108-174 MHz. The resource outlines supported modes including AM, FM, SSB, CW, and RTTY, noting a tuning step resolution down to 1 Hz and a frequency stability of ±5 ppm. Key electrical specifications are presented, such as a 13.8 VDC power supply requirement, current drain figures for RX (1.8-2 A) and TX (Max 20 A), and RF output power ranging from 5-40 W for AM and 5-100 W for FM, SSB (PEP), and CW. The entry details the triple conversion superheterodyne receiver system, listing IF frequencies at 69.01 MHz, 9.01 MHz, and 455 KHz, along with sensitivity ratings for various modes and bands. Transmitter section specifics include modulation systems and spurious emission levels. Additional features like a built-in auto ATU, electronic keyer, simple spectrum scope, DSP, and CI-V computer control are noted. The page also lists related documents, modifications, and an extensive array of optional accessories, including various filters, microphones, and external tuners, providing a complete profile of the IC-746.

Excel sheet containing technical comparisons of commercial HF portable antennas compiled by ON4SKY. Includes pictures, manufacturer, db gain, band coverage, F/B ratio, price, weight and dimensions.

High-power 3-500 HF linear amplifier by Don Pinnock G3HVA

Improvements to Using the Heath SB-200 Linear on Six Meters by Ron Klimas, WZ1V

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

The ICOM IC-7300 is a cutting-edge HF transceiver that has garnered significant attention since its release. This review, published by ARRL in QST, provides an in-depth analysis of its features, performance, and usability. The IC-7300 is known for its direct sampling technology, which enhances its sensitivity and selectivity, making it a favorite among amateur radio operators. The review covers various aspects, including the user interface, audio quality, and overall operational capabilities, providing valuable insights for both new and experienced hams. In addition to its technical specifications, the review discusses the IC-7300's performance in real-world scenarios, such as DXing and contesting. It highlights the transceiver's ability to handle weak signals and its versatility across different modes. The review serves as a helpful guide for those considering the IC-7300 for their station, offering a balanced perspective on its strengths and potential drawbacks. Overall, this review is an essential resource for anyone interested in the ICOM IC-7300 and its place in the amateur radio landscape.

A 2-way remotely operated HF antenna switch, based on an idea supplied by G3YEU

The DXrobot, operational since 1999, offers a free, non-commercial service primarily for the VHF ham radio community. It specializes in automatic real-time E-skip warnings for **144 MHz** in both Europe and North America, delivered via email or SMS. Additionally, the system provides automatic aurora alerts for _50, 70, and 144 MHz_ openings through the same notification methods. Beyond real-time alerts, the DXrobot facilitates the reception of the latest DX-cluster spots via email, a feature useful for operators without immediate WWW or cluster access. The service also displays recent E-skip and aurora spots detected by the DXrobot on 50, 70, and 144 MHz, with updates every five minutes. Historical data includes lists of all DX spots from the previous day on 50, 70, and 144 MHz, updated daily. Key propagation data, such as MUF timeline, Solar X-rays, Geomagnetic Field, and Estimated Kp index, are also presented.

Summarizes a portion of the FCC rules 47 CFR 80.371(c) and 80.373(f)

F5RDH project of a transverter, that can receive input in HF and convert output to 144 Mhz in french

Presents a comprehensive guide for constructing a broadband Hex Beam antenna, a popular directional array for HF operation. This design offers a compact footprint and excellent gain characteristics, making it suitable for limited space installations while providing significant performance advantages over omnidirectional antennas. The resource details the specific dimensions for a five-band Hex Beam covering 20, 17, 15, 12, 10, and 6 meters, emphasizing the critical element spacing and wire lengths required for proper resonance and pattern. It outlines the construction of the center post, spreaders, and wire elements, along with the feed point assembly, ensuring proper impedance matching. The project aims for a forward gain of approximately **5.5 dBi** on most bands, with a front-to-back ratio often exceeding _20 dB_. Building this antenna requires careful measurement and assembly, but the resulting performance provides a substantial upgrade for DXing and contesting.