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no tune SSB/CW transceiver for 1296, 2304, 5760 and 10368 MHz

The Kenwood TH-F6A handheld transceiver can achieve an extended transmit frequency range of 137-174 MHz, 216-235 MHz, and 410-470 MHz by removing a specific diode and chip resistor from the main PCB. This modification also expands the receive range on the A-band to 142-152 MHz, 216-235 MHz, and 420-450 MHz. For the TH-F7E, the transmit range extends to 137-174 MHz and 410-470 MHz, with a corresponding receive range on the A-band. Performing these hardware changes will reset and initialize the radio's memory contents, necessitating prior backup of important channel frequencies. Instructions are provided for constructing a homemade PC programming cable compatible with the Kenwood TH-G71A, TH-F6A, and TH-F7E. The interface utilizes an RS-232-to-logic (0-3.3V) level-shifter and a full-duplex serial connection, adapting the Kenwood PG-4S cable schematic for the TH-G71's 2.5mm and 3.5mm phono plugs. Specific schematic tweaks include changing R1 from 150 ohms to 1K ohm to optimize power from the serial port and adding a 150K ohm resistor between the Radio TXD and ground to manage the 3.3V I/O pin. Detailed plug pinouts for the 2.5mm and 3.5mm connectors are presented, with the interface's TXD connecting to the ring of the 2.5mm plug and RxD to the shield of the 3.5mm plug. Ground connects to the shield of the 2.5mm plug, while the tips of both plugs are no-connects. Debugging procedures cover verifying positive and negative power rails from the serial port, checking component polarities, and testing level-shifting and inversion functions of the interface. Software setup involves enabling "TC ON" (Menu 15 for TH-G71, Menu 9 for TH-F6) and using Kenwood's MCP programming software.

MMMonVHF maintains the data for 6m, 2m, 70cm and 23cm bands in collaboration to LA0BY. This site allow display of a beacon map and latest beacon spots.

J-Pole Antenna by K4TAX

The FTBVR5K software facilitates comprehensive memory management for the Yaesu VR-5000 scanning receiver, supporting operations such as modifying, moving, adding, deleting, masking, and unmasking individual memories. It allows for importing and exporting memory definitions via CSV files, sorting memories by frequency or name, and identifying duplicate frequencies within the receiver's configuration. The program also supports the creation and modification of bank definitions, management of PMS (Programmable Memory Scan) definitions, and adjustment of PMS scanning ranges. Additionally, users can print detailed reports of memories, banks, PMS definitions, rig settings, and S.CALL details, with visual cues like red highlighting for masked memories and yellow for the priority channel. FTBVR5K provides functionality to alter values within the VR-5000's Set and Config menus, and to change S.CALL station names and frequencies. The application operates on standard Windows PCs, including Windows XP, Vista, 7, 8, and 10, requiring an available COM port for transceiver connection, which can be a conventional serial port or a USB adapter. A minimum screen resolution of 800 x 600 is supported, with 1024 x 768 recommended for optimal usability.

Topic on eham forum on how to start building a VHF ham radio repeater.

A complete list on Long Beach Frequencies. Long Beach Police Penal Codes, and Police 10 Codes

This antenna allow transmission and reception on all bands between 7Mhz and 28 Mhz. Similar in concept to the Miracle Whip by VK3YE

A schematic design of the W3DZZ antenna in portugues with description of trap building

Band-pass filters can be critical components in competitive stations. This setup may help put your station on the map.

Revisiting the WA2EBY broadband HF amplifier

A portable VHF home-made Yagi-Uda antenna, that is extremely easy to build and very cheap. Moreover this antenna, while dismounted is just 1 meter long, and the total weight is just 100 grams.

New User Tips for VHF-UHF Operation by Dave Schultheis WB6KHP

A well documented article on a small magnetic loop antenna for the 40 meters band

A free application that searches more than 100 web-accessible sources to locate QSL information for a callsign that you enter once

The ZS6BKW wire antenna, a variant of the G5RV, utilizes a specific 13m (42.6 ft) length of 450-ohm window line as its matching section, feeding a 28.5m (93.5 ft) flat-top element. This design aims for lower SWR on 40m, 20m, 17m, 12m, and 10m compared to a standard G5RV, often achieving SWR values below 1.5:1 on these bands without an antenna tuner. The feedpoint impedance transformation provided by the window line allows for direct connection to 50-ohm coax on multiple bands. F4FHH's experience involved constructing the ZS6BKW and evaluating its performance against an _OCF dipole_ (Off-Center Fed) on various HF frequencies. The article includes observations on SWR readings and operational effectiveness, highlighting the ZS6BKW's suitability for multi-band operation. The antenna's overall length, including the flat-top and window line, is approximately **41.5 meters** (136 feet), making it a significant wire antenna for fixed station use. Comparative analysis with the OCF dipole provided practical insights into the ZS6BKW's advantages and limitations, particularly concerning bandwidth and tuner requirements.

Trader net frequencies

Compiling an extensive collection of technical information, the Repeater Builder's website serves as a critical resource for those involved in amateur and commercial repeater systems. It covers a broad spectrum of topics essential for the design, construction, and ongoing maintenance of these vital communication hubs, drawing from years of practical experience in the field. The site provides detailed insights into various aspects of repeater technology, including specific information on VHF and UHF bands, such as 2-meter systems. Users can find data related to repeater logic, control systems, and interfacing with other radio infrastructure, all presented with a focus on practical application. Authored by Kevin Custer, W3KKC, the content reflects a deep understanding of repeater operations and engineering, offering guidance that extends beyond basic setup to advanced troubleshooting and optimization.

Live space weather and propagation data, in RSS (XML) format.

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

Remote HF - VHF - UHF radio station using TS-2000 and remoterig devices

VHF/UHF DX site showing latest propagation, software, radio dealers, awards, maps etc.

Memory management program for the FT-60R/E FM handheld.

A small portable antenna tuner for HF and VHF bands by ON6MU

The following frequencies are assigned to datacommunications in the HF bands within the UK By RSGB data communications committee information.

Based on DL6UW Yagi antenna's design-formula The forward gain is 13.6 dBi (about 11.5 dBd) and it's pretty small, about 1,5 m in length

A popular 2 meter antenna returns in an improved, easier to reproduce form, 2008 QST article

Local and DX contacts from tight spaces, it works from 40 to 17 meters

Features and specifications for Yaesu FT 857D

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.

An interesting article on building a 4 elements yagi antenna with gamma match for the 2 meter band. This article include two videos demonstrating assembling procedure by KG0ZZ

A telescopic pole that you adjust to suit the band you're working on , tested on 40 20 and 15 meters band by M0PZT

Automatic Picture Transmission (APT) is used by Satellites to enable a fully automated unattended reception of the transmitted pictures.

Proppy: Online HF propagation predictions using the ITU Recommendation P.533-13 Propagation Prediction Application.

A 400 W 144 MHz GI7b Linear amplifier

Here is an antenna for the nineties. It's strong, computer designed, and has lots of gain. It is a full size, four element beam on 10, and three elements on 15 meters

HFUnderground.com is dedicated to documenting longwave, mediumwave, and shortwave stations, including broadcasters, utility/military stations, pirate radio and spy numbers stations.

Moon bounce EME, meteor scatter and weak signal operations, introduction by ARRL.

HFCC manages and co-ordinates global databases of international shortwave broadcasting in keeping with International Radio Regulations of the ITU. Operational Schedule, available for free download and iteractive schedule

Low Noise Antenna pre-amp for SAT, EME & DX-ing

Different band dipoles can be put together with a single feed, learn how by W8HDU

IC706 Specifications by universal radio inc

Live feed from Warren county fire dep. radio

A project for a four element cubical quad antenna for 144 MHz in portuguese

Homemade HF Tuner by PE1OPM

Build an HF antenna tuner by VK5AJL

The NAVTEX system is used for the automatic broadcast of localised Maritime Safety Information (MSI) using Radio Telex (also known as Narrow Band Direct Printing, or NBDP).

An RF power supply for 144 MHz schematics and instructions

A compact Quad Antenna for the HF Bands by GM0ONX

A pdf file with review of RTTY contests software available on the net and information on how to operate a RTTY Contest, by RSGB.