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Resource for finding data on vacuum tubes.

Influence of batteries on RFI and noise generation by k0bg

Electronic components dealer stocking RF adapters and many other popular items.

An amateur radio contest log sheet printable in A4 format, useful for portable operations, free to download PDF File.

Front Panel designer by panel pool

TrunkStar780%u2122 is a high-performance, full-featured software package for Uniden® BC780XLT trunking scanner. Data management and operational control over the BC780XLT is provided.

Useful exercise sheet to learn morse code reception. In A4 format PDF File, it contains groups of 5 characters commonly used while learning morse code reception.

Complete catalog of low noise preamplifiers and microwave Gunnplexers.

Navtex Maritime Safety Information Broadcast Channels

A moon tracking software capable to drive the rotation of your antennas in azimuth and elevation

OSX/Mac and Windows versions of SdrDx. Supports RFSPACE, FunCube Pro, Andrus MK1.5, AFEDRI, FunCube Pro Plus, Peaberry, RTL sticks (RTL supported under OS X only, via this OS X RTL server) and Softrock SDR receivers.

This article compares two commercial vertical antennas for the 4-meter amateur radio band: the Watson WVB-70 half-wave and the Sirio CX4-71. The Watson measures 2.03m in length, costs around £40, and exhibited adequate performance but required additional waterproofing after rain affected its VSWR readings. The longer Sirio CX4-71 (3.02m) performed noticeably better, delivering signals approximately 2 S-points stronger than the Watson. The Sirio demonstrated high build quality, a stable 1.2-1.4:1 VSWR, and weather resilience, though minor VSWR fluctuations were observed during rain and frost. Both antennas are half-wave designs requiring no ground plane radials.

This is the 195-foot tall rotating Rohn 55G tower at W8JI with yagis for 40 20 15 and 6 meter bands.

Antenna Analyzer AIM4170 by W5BIG from Array Solutions

The information in this article has come from many amateur sources, the most notable was from WA6TEY (sk 1985) Ray Frost, who was a pioneer of VHF Quad designs and one of the best Southern California Transmitter Hunters. Ray built hundreds two meter quads in single and paired configurations as well as his famous mobile radio direction finding quad.

A page by 9A7PJT dedicated to HB9CV yagi antennas includes link to the HB9CV calculator program and some interesting plans

Magnetic loop for 20 to 6 metres pedestrian mobile by VK3YE

Radio restoration in new york

A 2m 70cm Dual Band J-Pole antenna for 35 USD. An excellent performing J-Pole type antenna, constructed from readily available materials.

Custom Design T-Shirt with No Minimum order (you can buy just 1) and NO Setup Fee. Will transfer your Favorite Images from JPEG's and E-mail attachments and from photo prints to Custom T-shirts with unbelievable Crispiness and Clarity of true Color Reproduction. Our image transfer paper is 11.5" x 8" heavy duty industrial grade.

Christian radio station 'The Overcomer' providing broadcasts via shortwave.

ARRL video review of the Yaesu FTDX-5000

Coaxial stub filters used at W7GJ

Servering the amateur radio community with a consolidated news center.

The Baja Net is one of the boaters favorite nets on the West Coast. It has a long history of handling traffic for mariners who are out of touch with friends and family. Several stations have phone patches enabling them to put you right on the line to talk to your loved ones.

For radio amateurs and electronics enthusiasts maintaining vintage tube gear, having accurate documentation for tube testers is crucial. Michael Marx, WB0SND, through SND Tube Sales, provides high-quality reproductions of these essential manuals. These aren't mere photocopies; each manual is digitally scanned, cleaned of imperfections, and professionally printed on a _Laserjet 5000_ with heavy card stock covers and plastic comb binding, often making them difficult to distinguish from originals. The catalog includes instruction manuals, schematics, and roll chart supplements for a wide array of classic tube testers. Operators can find documentation for popular models such as the _Hickok 539B/C_, _AVO CT-160_, and _B&K 700_, along with military-grade testers like the _TV-7_ and _USM-118_. Many listings also offer specialized supplements for obsolete or foreign tubes, ensuring comprehensive coverage for diverse tube collections. WB0SND's offerings extend to calibration instructions and data for specific adapters like the _Hickok CA-4_ and _CA-5_, providing critical support for precise tube testing.

This voice-keyer-interface connects between a Yaesu FT1000MP and a PC's sound card & COM port. It can be used as a voice-keyer with Contest Voice Blaster and as a voice-keyer and CW-keyer with Writelog.

An Unorthodox Antenna, originally by W3AWH is considered a multi-band antenna suitable for fixed location use and as an easily deployable portable antenna for events such as Field Days.

Yaesu MH-31 Electret Condenser Mic Modification

Power connectors, power cables, coax cables, wires, batteries fuses and holders and tools

The N3UJJ multi band cage dipole antenna project thay can fit a small property

P49V Aruba Ham Radio Rental

This calculator is designed to give the horizontal length of a particular dipole including Tees, antenna, or one side of it, for the frequency chosen. Enter the desired frequency and select the desired calculation from the drop box

A web page for uhf & hf cb operators & scanner hobbtists

Yaesu VX-8R specifications and picture

K8CU builds a classic 1967 QST semiconductor project during the 40th anniversary year of the original project publication.

WWCR-Shortwave, Nashville, Tennessee, USA

This tutorial provides step-by-step instructions for setting up the ICOM IC-7300 to work with WinLink and WinMor. The process begins with downloading the necessary USB driver from ICOM Japan, followed by configuring the radio settings through the menu. Key settings include selecting the correct output and data modes, as well as ensuring the USB serial function is properly set. Once the radio is connected to the PC via USB, the drivers will install automatically, allowing for seamless communication. After confirming the installation of the USB Audio CODEC and COM port, users are guided to download the RMS Client Software for WinLink. The tutorial emphasizes the importance of understanding the WinLink system and provides links to additional resources for setup. Finally, it details how to configure the WinMor modem settings, ensuring the ICOM IC-7300 is ready for effective digital communication. This guide is essential for operators looking to enhance their digital capabilities using the IC-7300.

An home made UHF 7 elements Yagi antenna project

Paul Harden NA5N has produced a superb guide to solar activity and HF propagation for the QRPer

An home made slim jim antenna for 2 meters band by VU2TQC

This article loaded with nice pictures and schematics, describes a 160-10 meter linear amplifier that uses a pair of 3-500Z triode power tubes. It was designed and constructed by William Moneysmith, W4NFR. The amplifier features fast warm up and 1500-Watt RF output with 100-Watts of drive.

A monster magnetic loop antenna for 160 meters band. This Magnetic loop is optimized for 1840 Khz + 50 Khz. PDF Article published on La Radiospecola 10.22

This document details the design and construction of the PA70H, a 50-watt RF amplifier for the 70MHz (4-meter) amateur radio band. Built around the Mitsubishi RD70HVF1 MOSFET transistor, the amplifier delivers 45-55W output with 3-5W input power while operating on 13.8V DC at approximately 7-8A. The PCB design incorporates multiple protection circuits including overcurrent, SWR, and temperature control. The amplifier features various control modes including GND PTT, +13.8V PTT, and RF VOX. Two versions are available: PA70HLI (requiring 100mW input with additional driver) and PA70H (for 3-5W input). The comprehensive documentation includes circuit diagrams, assembly instructions, and performance data showing successful operation from both 100mW and 3.5W input sources.

Measurements for building a full wave loop using wire

Eham.net review of ICOM IC-2720H

This circuit stores a single morse code message as bits in an EPROM chip, the message is sent to a relay which can key a CW transmitter.

Receiver tests of some transceivers and receivers including FT-1000, FT-2000, IC-751, IC-756 IC-7800 and TS-870

Maker of optical spectrum analyzers, digital oscilloscope, digital power meters and more test equipmente related products

This is the schematic of asolid-state 7 MHz QRP CW transmitter by VU2NAN