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Common faults, and modifications for the kenwood TS-430 S

A Primer for the new Packet Radio operator

This high antenna require a large ground composed by 40 radials. It's not very handy expecially in windy situations but is very powerfull in pile-ups. In italian

Home made bazooka antenna for 2 meters band

A High Efficiency Extended Length Mobile Antenna The antenna itself is 3.42 meters or 11 feet 2 inches long from the top of the mounting spring to the tip.

Fatpigdog's Real Time FFT Audio Spectrum Analyzer. User interface has the look and Feel of an HP Spectrum Analyzer. But, in addition to the regular Spectrum Plot, it also produces detailed Waterfall plots. The user can optimize the color map, chosing from a wide assortment of color themes. This analyzer supports multiple traces, trace arithmetic and normalization.

A Center-Fed Half-Wave Dipole is probably the simplest of antennas to construct and use. It is usually suspended between two supports, from it's end insulators, and has the feedline hanging from the center.

Freeware program, special and easy to use packet program for communicating with ISS, PCSat and other 'compatible' sats. Can also be used for basic normal packet.

Live scanner feed and police and fire feeds

Inline RF Power & VSWR Meter. A DIY meter 0 to 30 Watt with Average and Peak. Circuit Description, Arduino Nano software code and part list to DIY your own Digital SWR Meter

Harger Lightning Protection is a full line supplier of lightning protection and grounding equipment, servicing the lightning protection, communications and electrical industries.

Search for call sign and display maps and dxcc info

A really simple receiving antenna for 80 and 160 meter dxing by WA2WVL

Tuning control of the Yaesu FT-736R multiband VHF/UHF transceiver.

A new method of feeding a dipole with toroids.

Equipment and procedures to monitor ACARS

Comprehesive page on TS-940 TS-940 reference maintained by ZL4AI Jeff

UK reseller for HF VHF UHF

The mirror-image J-Pole is very easy to construct and requires only two T-Fittings plus a length of copper pipe.

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.

Project by VE7GC

Official ICOM distributor for The Netherlands, Belgium and Luxembourg

End-Fed Half-Wave Antennas (EFHWAs) are analyzed for their utility in portable QRP operations, emphasizing their simplicity, efficiency, and predictable radiation patterns compared to other portable antenna types. The discussion contrasts EFHWAs with vertical antennas, random length wires, and center-fed dipoles, highlighting the common pitfalls of each, such as ground system dependency for verticals and feedline issues for dipoles. The article details the electrical half-wavelength calculation using the formula L (Ft) = 468/F(MHz) and explains how EFHWAs can be resonant on harmonic frequencies, enabling multiband operation. Various deployment configurations are presented, including the inverted L, inverted Vee, sloping wire, and vertical setups, each with specific advantages for radiation angle and polarization. For instance, a vertical EFHWA offers a low angle of radiation suitable for DX contacts without requiring an extensive ground system. The resource also addresses the counterpoise requirements, suggesting a quarter-wavelength wire or connection to a metallic structure for decoupling. A schematic diagram for a simple parallel-tuned circuit tuner, based on the _Rainbow Bridge/Tuner_ design, is provided, detailing component values for 30 and 40 meters, including a 6 microhenry toroidal inductor and a 20-100 picofarad mica compression capacitor. The tuner's adjustment process for SWR matching is also outlined.

WebSDR.org is a WebSDR network. List of all active WebSDR radios.

Over 75 years of engineering expertise underpins Bird Electronic's offerings in RF power measurement, critical for maintaining peak performance in amateur radio stations and professional communication systems. The company specializes in a range of test equipment, including wattmeters, SWR meters, and antenna analyzers, essential for optimizing antenna systems and ensuring efficient power transfer. Their product line extends to various RF components such as filters, cables, and connectors, all designed to meet stringent technical specifications for reliability and accuracy across diverse frequency bands. Bird Electronic's instruments, like the _Bird 43_ Thruline Wattmeter, are widely recognized for their robust construction and precise measurement capabilities, providing hams with confidence in their station's operational parameters. These tools enable accurate assessment of forward and reflected power, SWR, and modulation characteristics, which are vital for troubleshooting and maximizing radiated power. The company's commitment to innovation ensures that its products remain relevant for modern RF challenges, from HF through microwave applications, supporting both traditional analog and advanced digital modes.

An interesting rotator interface that interfaces a pc to a rotor or rotator controller, emulating a Yaesu GS-232A/B and Easycom protocols, made with Arduino

Eighteen-part tutorial on packet radio in HTML and ASCII format from Larry Kenney, WB9LOZ

PC power supply conversion for ham radio use. Slide show overview showing how convert PC Power supplies to ham radio use presented at the August 2007 FSARC meeting.

Experience of band filters, for a contest multi operator enviroenment

Sells leading-edge voice and digital communications products to the world-wide military, government, industrial, and amateur radio marketplaces. Bluetooth Remote Audio/PTT, Rig Controller with Audio & PTT , HamLinkUSB Rig Control, Noise filtersm antenna analyzers, Multimode Data Controller, TNC, Packet Radio Terminal Node Controller. USB2RS232

When one operates at low power on SSB, speech processing becomes almost essential to get through the QRM. The circuit is a low cost speech processor that will perform well with a minimum of construction effort.

Details a practical QRP wattmeter construction, leveraging a simplified SWR meter design by JA6HIC. The project focuses on a forward-only power measurement circuit, providing a functional instrument for RF power levels from milliwatts up to 5 watts. It maintains a 50-ohm input and output impedance, suitable for typical QRP transceivers and antenna systems. The resource includes the schematic for the "VSW" (Very Simple Wattmeter) and outlines a six-step alignment procedure. This calibration process involves using a known RF source up to 5W, setting full-scale deflection, and marking power increments. It also addresses minimizing frequency effects on readings with a 100pF trimmer capacitor, noting that measurement error is highest at the lower end of the scale. Construction notes mention using a piece of RG-213 coaxial cable for the inductance and coupler, with the wattmeter assembled in early 2003. The author provides an example measurement showing 0.8W into a dummy load and 1W into a 3-element beam.

Transceivers, Receivers and some Equipment for Amateur, CB, maritime and aircraft with world wide shipping,

The function of the calculator is to give all of the needed sizing to construct a good 5 element quad antenna for amateur radio use.

Demonstrates a comprehensive logging and contest program for Windows, _UCXLog_, designed to assist amateur radio operators in managing their QSO records and participating in competitive events. It integrates essential features such as transceiver control for single-operator two-radio (_SO2R_) setups, CW keying via COM/LPT ports, and SSB/RTTY operation through soundcard interfaces. The software also provides DX cluster connectivity via packet, internet, or Telnet, alongside robust statistics tracking for awards like _DXCC_ and _IOTA_, locator management, and greyline map display. Enables operators to efficiently handle log import/export functions, print QSL cards, and maintain detailed records of their contacts. The program's network capability facilitates multi-operator environments, while its support for various digital modes and rig control protocols enhances operational flexibility. Regular updates, including beta versions, are provided, ensuring ongoing development and feature enhancements for the amateur radio community.

Map of USA Districts

Great first time J-pole project. Covers most of the basics. This small and thin design also makes it good for several stealth applications.

The DRM Software Radio is based on the proven Fraunhofer DRM engine, which is considered to be the most advanced DRM engine today, built around fully licensed proprietary DRM encoding technology.

BesserNet Reflectometer is a fun SWR calculator and simulator Java applet

Active digital mode frequency list compiled by Jason Buchanan - N1SU

Homebrew Sector Antenna for Wifi ISM band (2,4GHz)

On 23cm the best way to obtain a good RX-sensitivity is to use a GaAs-FET in the front-end, since these devices show very low noise figures.

KGKSDR is my attempt at some SDR decoding software. I'm putting this software together purely as a learning exercise, to better understand the mathematics behind SDR in general.

Portable Vertical Antenna for 75m and 40m featuring Low radiation angle for DX, easy to install and to match 50 ohms

Repeaters, transmitters, receivers, small power Amps and Controllers

Two element X-Beam is a high-performance broad-band antenna that is ideal for Ham radio operators with limited space. X-Beams are inexpensive and easy to build. The performance of the simple X-beam is amazingly similar to larger, more conventional antennas by 4S7NR

A 3500kHz - 3579kHz range transceiver, output 250 mw by SP5DDJ

RightMark Audio Analyzer

This is a base-loaded vertical antenna that mounts on the car's roof. The loading coil is designed as a variable inductor, with a three-legged chariot that travels up and down inside the coil, with grooved brass wheels running on the coil turns, and driven by a slotted rotor tube.

Calculate dimension for discone antennas online