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Four or Five turn one meter loop antenna for 80 and 160 meter band. This home made receive only antena can be assembled in a small place.

March/April 2010 will be QRV from March 16th till April 4th on IOTA NA-100, 6-80m - mainly in RTTY, PSK and SSB QSL via DL7AFS

A quarter wave vertical omni-directional antenna for 7 MHz. Formulas for dimensions in feet and meters are provided. Ideal radial angle is between 35° and 45°. Velocity factor (Vf) varies based on coax type.

lighthouses and lightships of ireland and northern ireland with arlhs reference numbers for all irish lights

Article on common Classification of Spy Numbers stations.

TCSWAT Lighthouse Awards from Turkey

YU7EF EF0206 2m Band 6 Element Yagi Antenna project, provides 11.8 dbi gain

The simple balcony vertical HF antenna made with plastic fishing pole. Just along the pole I install copper wire in 7 meter length. Then was installed ATU. It was used home brew tuner. For each band was used one counterpoise in length 0.8 x lambda/4

This article include a circuit that allows a cheap 0-1mA meter to be used as a micro-ammeter or a milli-voltmeter

927.1250 MHz Santiago Peak, CA USA

The Advanced ATV Repeater is probably the most versatile ATV repeater controller in The World. It can run entirely under the operating system or all repeater functions can be controlled from any other computer

Icom PW-1 1kw Linear Amplifier described by WA0SXV

The Primary N6OCS Repeater is located at 5700 feet on Santiago Peak in the Santa Ana mountains.

A dynamic collection of high latitude geomagnetic data from 12 Canadian observatories

Product information, resources, enhancements and links of the popular ICOM IC-756PRO III

Amarteur Radio Society Of India, the national society, is issuing Worked Republic of India (WRI) Award to VU and Dx operators.

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

Alaska 10 meter Beacon

Master Callsign Database Editor allows to create and modify Super Check Partial database files used by many contesting programs in DTA and SCP formats. The files produced by Master Editor in DTA format can be used with CT, WriteLog, TRlog, SD, and others. The SCP versions of the produced files are for use with Win-Test, N1MM+, and others. Master Editor allows to create a callsign database from a separate log or from a set of logs in the Batch Import mode.

A balun is a MUST for dipoles or similar antennas when they are feed with coaxial cable. From the RF point of view, the shield can be modeled as two conductors, the internal shield (the real shield, this is, ground) and the external shield, who is really far to be ground. In this way, your dipole has 3 arms, the two from the dipole and the coaxial cable shield (external face)

Wireless Society of Southern Maine Projects, instructions and photos for many ham radio projects and experiments, including antenna construction and modelling, kit building, station setup, restoration and more

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.

How to modify your scanner or receiver with a discriminator output. If you want to decode and monitor digital (FSK and PSK) systems seriously, a discriminator tap is an absolute prerequisite.

Online coloured Azimuthal Map Generator. By default, this map shows the current gray line. The parts of the Earth that are currently in the sun (i.e., daytime) appear brighter, and the parts of the Earth that are experiencing night appear darker

Operating ham radio in international waters

27 oktober - 6 november 2012 30/20/17/15/12/10/6 meter band ssb-cw-rtty

Home page for the TARPN node design and promotion. This is an Off-The-Grid Text messaging and educational packet networking project. No Internet required or desired.

A review of the Alpha 87-A power amplifier by WD0M

3C0W Annobon Island Online Log

A short 3 element LFA Yagi for 50MHz with a 1.94M boom. This antenna has been designed in order to minimise the upward and downward lobes typically seen the the EL plane on Yagi antennas.

But it is only a couple of dB, The Effect Of Insertion Loss On Transmitted Power (dB to percentual loss) Original Information Provided by Neil McKie WA6KLA

Clarifies the intricate process of calibrating the _Elecraft K2_ dial, addressing common user challenges and lively discussions on the Elecraft reflector. Wilhelm, W3FPR, dissects the K2's PLL synthesizer design, chosen for its low phase noise, kit-friendly duplication, and cost-effective components. The resource emphasizes the critical role of the 4000.000 kHz reference oscillator's accuracy during CAL PLL, CAL FIL, and CAL FCTR functions, noting its dependence on temperature and crystal stability for optimal performance. Explaining the K2's frequency display, the document reveals it relies on microprocessor-driven look-up tables generated by CAL PLL for VFO values and CAL FIL for BFO values. In SSB and RTTY, these combine, while CW and CWr modes also factor in the sidetone pitch. The author details inherent limitations, such as the 10 Hz increment resolution of the dial and varying PLL step sizes—from 3 Hz on 160 meters to 10 Hz on 10 meters. BFO increments range from 20 to 35 Hz, collectively limiting practical dial accuracy to within **20 Hz** with diligent effort, or **30 Hz** for a slightly less demanding task. The guide outlines a four-step calibration procedure: setting the reference oscillator, running CAL PLL, running CAL FIL, and setting all BFOs. It highlights the _N6KR Method_ as a particularly easy and accurate approach, requiring only the K2 and a known frequency source like WWV for zero-beating, eliminating the need for external test equipment.

10-40m TY1TT dx pedition to Benin 2014

Fixing a problem on the Alpha 87A amplifier by replacing a blower by WD0M

Calculate distance, bearing and more between Latitude/Longitude points. This page presents a variety of calculations for lati­tude/longi­tude points, with the formulas and code fragments for implementing them.

Windows log software for the popular RD contest, usually held in Australia in mid August.

Experiments on vertical antennas for HF bands.

Norfolk Island 6m DXpedition 25 March to 07 April 2012 VK9N/ZL1RS

Accurate county coverage limited to Tehama, Butte and Shasta at the moment

A HF power amplifier with a push-pull of AFT09MS015N. The (small-signal) gain of the amplifier is around 26 dB in the lower HF band and goes down to about 24 dB on the higher end and still around 21 dB at 50 MHz. Its input matching is relatively good at the lower HF and degrades above 10 MHz.

Using DX4WIN with ICOM radios and the ICOM PW-1 RF power amplifier

FP/KV1J July 2014 DXpedition to Miquelon

The Narrow Band Emergency Messaging System (NBEMS - pronounced N-beams) is a suite of software programs based around Fldigi and designed for point-to-point, fast, error-free, emergency messaging which takes up very little space on the ham bands.

Determining the characteristic impedance (Z) of an unknown coaxial cable, a common challenge for many radio amateurs, can be resolved with a straightforward method. The impedance of a coaxial cable is derived from its inductance and capacitance, and importantly, these values are independent of the cable's length or the operating frequency. This means that measuring a random length of cable, such as 20 meters, provides sufficient data for calculation. The core of this technique involves an LC-meter to obtain the inductance (L) in microHenries (uH) and capacitance (C) in microFarads (uF). The impedance is then calculated using the formula Z = L/C. For instance, a measurement yielding L=1.2uH and C=450pF (0.00045 uF) results in an impedance of 51.6 Ohms, closely matching **RG-58** specifications. Similarly, a TV coaxial cable with L=1.8uH and C=320pF (0.00032 uF) calculates to 75 Ohms. While the accuracy of this method, depending on the LC-meter's tolerance, is approximately 10%, it proves sufficiently precise for practical determination of unknown coaxial cable impedance, as noted by Makis, SV1BSX, who credits Cliff, K7RR, for the formula's dissemination.

February 10-20, 2012 Winter DXpedition to Miquelon Island

Enables Android users to operate various _miniVNA_ antenna analyzers via Bluetooth, USB, or Wi-Fi, providing a portable solution for RF measurements. The application supports full control over data acquisition, offering features like custom frequency range selection from 1 KHz to the VNA's full range, and automatic screen adaptation for diverse Android device resolutions. It facilitates intuitive, wizard-based calibration for both reflection and transmission modes, saving calibration data for different VNA types (Standard, Pro, Pro with Extender) to avoid repeated procedures. The software displays critical parameters such as SWR, |Z|, Return Loss, Phase, Rs, and |Xs| on 2-axis graphs or Smith charts, with multi-touch gestures for zoom and frequency shift. It includes a frequency generator mode with independent channels and attenuator control for the miniVNA Pro, along with a sweeper function. The cable data mode automatically calculates phase and loss, measures cable length from less than 1 meter to hundreds of meters, and includes a table of common coax cable velocity factors. An experimental X-tal mode measures resonance frequency, Rs, and Q. Data export options include CSV, ZPLOT, and S1P formats, with CSV import capability. The application also features an SM6ENG Audio mode for SWR tuning without visual reference and provides a miniVNA battery voltage indicator. It supports a wide frequency range, with the miniVNA Extender extending coverage up to **1500 MHz**. The application is compatible with Android version 2.2 and later, tested on devices like the _Galaxy TAB 7.7 P6800_.

Filters and replacement parts for the Drake R-4C receiver by Sherwood Engineering Inc

N4PAL 10 Meter, 28.214MHz Radio Beacon Site Information and Siginal Report Logging

The areas noted in the forecast have the necessary atmospheric conditions to produce tropospheric bending of VHF, UHF and/or microwave radio waves. Tropospheric bending extends the range of radio & TV stations well beyond their normal limit and thus increases interference amongst stations as well.

The "DIY Telescopic-V Antenna £35" project showcases the creation of a budget-friendly, portable telescopic V-shaped antenna inspired by commercial designs. Using eBay-sourced telescopic whips and custom mounting solutions, the author documents their process, testing, and adaptations. Despite challenges like weather and missing tools, the antenna performed well across multiple bands, enabling successful QSOs. Future improvements include exploring loading coils and testing in better locations. The compact design offers versatility for amateur radio enthusiasts seeking an affordable and practical solution.