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This page is a live feed for Most of South King County, WA Fire and EMS as dispatched by Valley Communications.

Phased vertical antenna system in french

The Assyrian Democratic Movement also known as ZOWAA . This political organisation is aiming to bring freedom and democracy to Iraq.

An easy method for erecting antenna masts using readily available material

Slot antenna and complementary dipole

The page discusses Axial-Mode Helical Antennas, focusing on turning helical antennas over perfect ground and modeling helices in NEC-2 for optimized design. It covers topics such as high-gain performance, broadband, impedance matching, radiation pattern, feedline, balun, near field, far field, and DIY applications.

A german documento on magnetic loop antennas

Antenna manufactuer, Panel antennas, sector panel antennas, high gain for ISM, MMDS, PCS, GSM, CDMA, TDMA, 400MHz, 900MHz,1.9GHz, 2.4GHz, 2.7GHz, 3.5GHz,5.8GHz. Broadband wireless applications for ISP,ASP.

Complex CAD and Optimization Software for Waveguide, Coax, Combline and Antenna components design and antenna modelling

Russian callsign prefix series: RAA-RZZ, UAA-UIZ, includs Amateur callsign system in Russia

About HF Wire Antennas for field day or any day a basic wire antenna article

A moxon antenna project for 70 cm band, test and results of this popular antenna model applies to UHF bands.

Helical antennas have long been popular in applications from VHF to microwaves requiring circular polarization, since they have the unique property of naturally providing circularly polarized radiation. Paul Wade W1GHZ

Outdoor equipment and electronics - handheld, base, mobile VHF, UHF and CB radios. Uniden emergency scanners. FRS and now GMRS 2-way radios.

Northern NJ's number one club. Weekly swap n shop/net, VE sessions 2nd Monday, Meetings, Second Tuesdays. E-mail us to learn more.

This HALO design is not ground dependent and can be mounted atop a section of PVC.

W6/PA0ZN CATV tuner based Spectrum Analyzer Building Project

Various publications through the years have shown how the SWR measured on a shorted (or open) feed line can be used to calculate feed line attenuation

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

Sometimes amateurs like to home-brew their power supplies instead of purchasing one off the shelf at any of the major ham radio retail dealers.

An easy mod to make the 1st IF of the Icom IC-7600 accessible and connect to a cheap RTL SDR dongle by VE4NSA

Map of ITU and IARU Zones at hamatlas.eu

Open source software designed to control and program the ICOM IC-R75 receiver

The Wireless Institute of Australia (WIA) provides an official directory and database of Australian amateur radio repeaters, detailing their locations, frequencies, and operational status. The resource includes downloadable files in PDF and CSV formats, along with a _Google Earth KMZ_ file for visualizing repeater sites across Australia, including Amateur, CB, and Marine repeaters. It also references external resources for various digital modes such as _IRLP_, _Echolink_, _D-STAR_, P25, Fusion, and DMR, providing links to their respective information sites. The WIA repeater data is cross-referenced with the _ACMA database_ to ensure accuracy, with updates typically occurring twice a year. The directory employs a color-coding system, where purple indicates repeaters carrying the WIA broadcast or callback channels, and a 'W' status denotes operational repeaters with the weekly WIA broadcast. The resource also outlines policies for removing unlicensed or non-operational repeaters from the PDF listing after specific timeframes, while retaining them in the CSV file for potential reinstatement.

There is considerable confusion as to what exactly a multiband vertical antenna is. The confusion concerns the method of feed, how much mismatch one can expect, how many radials are required, how the particular antenna is built for multiband use, plus some other points.

Lowering an NVIS or N.V.I.S. antenna very close to the ground enhances NVIS operation

Free software to operate your own Internet remote base ham radio station. Client module allow remote control to your ham radio station and to other radios available on the net, Host module instead allow to publish your radio in the internet.

An inexpensive condenser microphone with excellent performance can be easily constructed with easily available parts.

A freware book on learning morse-code. The Art & Skill of Radio-Telegraphy Third Revised Edition by William G. Pierpont N0HFF, online version available in multiple languages

Radio Free Asia (RFA) is a private, non-profit corporation broadcasting news and information in 9 languages to listeners in Asia

A Quad Loop antenna for 17 meter band

The G5RV JR cover 10-40 meters band a project by PU2OKE

BaseStation is a Windows application written originally for the SBS-1 family of Virtual Radar Receivers.

With over 20 years of experience, Proyecto 4 operates as a specialized ham radio retailer in Madrid, Spain, providing a diverse inventory of transceivers, antennas, and related accessories. The store features popular models like the _ICOM IC-705_ and _ICOM IC-7300MK2_, alongside Yaesu transceivers such as the _FTX-1 Optima_, which delivers 100W on HF and 50W on V/UHF bands. The product range includes mobile and portable antennas, such as the D-Original DX-NR770HB, offering 3 dB gain on 144 MHz and 5.5 dB on 430 MHz, and the Diamond RH-770 with a BNC connector. CB radio enthusiasts can find the Anytone CB SMART II AM/FM transceptor and the Telecom LS145 mobile antenna, rated for 500W and 4 dB gain on 26-30 MHz. Proyecto 4 emphasizes its in-house technical service, inviting customers to visit their laboratory for repairs and technical consultations via sergio@proyecto4.com. The store also highlights customer reviews and offers promotions like Yaesu Cashback, providing savings up to 100€.

SARA is a dedicated group of people that formed an international society to learn, trade technical information and do their own observations of the radio sky

Welcome to the official Home Page of SouthEastern Repeater Association Inc. SERA is the largest Amatuer Radio Coordination organization in the United States. SERA represents Kentucky, Mississippi, North Carolina, South Carolina, Virginia, Tennessee, West Virginia and Georgia

Detroit Fire Department Radio Feed

This resource, "Transistor Audio Preamplifier Circuits," offers comprehensive design guidelines for constructing **bipolar transistor** audio preamplifiers. It delves into critical aspects such as quiescent current setting, voltage gain calculation, and the impact of various component choices on circuit performance. The content provides several _schematic diagrams_ illustrating different preamplifier configurations, including single-stage common emitter and two-stage designs, alongside explanations of their operational characteristics and practical implementation considerations. The analysis extends to frequency response, noise performance, and distortion, providing insights into optimizing these parameters for specific audio applications. The resource presents calculated gain figures for various stages, demonstrating how to achieve desired amplification levels. It also discusses the importance of proper power supply decoupling and input/output impedance matching, crucial for integrating these preamplifiers into larger audio systems or ham radio transceivers. The practical application of these designs is evident in their suitability for microphone preamplifiers or general-purpose audio amplification.

Fractal Quad Yagi Antenna by KF7BS published on 73 magazine October 99

Schematic of a regulated 0-24v 2A Power Supply

Quad and loop antennas comparisons, evaluating the impedance and gain of both antennas and considerationso n horizontal loop antennas for low bands by PA0FRI

Open source software designed for the Yaesu VR-500 receiver.

Serving Tarrant, Parker, Wise counties, and city of Fort Worth, Azle, Springtown, Boyd, Weatherford, Saginaw

Arduino uno universal VFO/BFO with Si5351 and TFT touch screen for BITX like txcvr

Increase TS 480 PEP power level

An Eprom Eraser with UV-Ray for 27Cxx Eprom (and similar, common in TNC) with a timer

Picture and specifications

Website dedicated to Coastal Radio Stations, includes frequency lists for memdium frequencies maritime stations

How to Increase your CW speed article by George Allison, K1IG as published on QST