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The Salvation Army Team Emergency Radio Network (SATERN) is a vital resource for amateur radio operators involved in emergency communications. This network facilitates the coordination of communication during disasters, ensuring that vital information can be relayed effectively. SATERN operates through a series of nets that connect operators across various regions, allowing for real-time updates and support during emergencies. Participation in SATERN not only enhances your skills as an amateur radio operator but also contributes to community resilience. Operators are trained to handle emergency traffic and provide assistance to those in need. By joining SATERN, you become part of a dedicated team that prioritizes safety and communication in times of crisis. The network encourages regular participation in drills and training sessions to ensure readiness when real emergencies arise.

Undestanding and measuring SWR, Standing Wave Ratio in antenna feed lines. This article also introduce basic concepts and usage guidelines of amateur radio antenna tuners

How Oscilloscope works and how oscilloscopes are done, with main components like Vertical Amplifiers and Horizontal Scanning or Sweep Circuits

My place in cyberspace for thinking out loud about the Three Rivers Area Montioring Association

Official web site of the Youngsters On The Air Italy 2015

A pocket-sized homebrew 40m CW QRPp/QRP transceiver

These band filters are based on 3 or 5 sections Butterworth band pass filters, maintaining 50 Ohm impedance, and when built around toroidal inductors, can be made very compact.

Online shop for electronic components, sensors, connectors, capacitors, resistors, passives, semiconductors from Baitron independent electronic components distributor.

DL7JV shares his practical experience building and testing capacitive antennas, initially skeptical of their performance compared to magnetic loops and mono-band dipoles. His interest was piqued after hearing a Spanish station running 100 Watts on 80 meters with a 1-meter Micro Vert, making DX contacts into PY and UA0, despite the antenna being only 4 meters high in a garden. This prompted DL7JV to investigate further, consulting resources from DL7PE and DL7AHW, the latter providing DOS programs like "Mitspule.exe" and "Spulenprg.zip" for calculating antenna dimensions and coil conversions. The article outlines the construction of two prototype antennas: one for 7.050 MHz using a 75mm PVC pipe and another for 3.550 MHz with a 110mm PVC pipe. Both designs feature aluminum foil condensers and coils wound from 1mm² H07V-K wire. DL7JV provides specific measurements for the condenser capacitance, surface area, diameter, height, coil inductance, turns, and wire length for both 40m and 80m versions, along with RG58 feedline lengths. Initial reception tests for the 7 MHz antenna, placed indoors, yielded impressive S9+5 signals from a German station compared to an S8 from a 42-meter roof-mounted loop, even hearing a Japanese station. Transmission attempts on April 4, 2004, despite moderate solar storm conditions, resulted in successful QSOs on 7 MHz with EA5OT (579/559) and on 3.5 MHz with YT1NT (579/559) and G4KKI (579/559) using 100 Watts. DL7JV notes the antenna's sensitivity to coordination and feedline layout, suggesting a modification from DL7AXO involving a 500pF fixed capacitor and coil tap for improved SWR stability. He concludes that while the capacitive antenna is space-saving and performs well for reception and 100W transmission indoors, its transmit performance doesn't yet match larger antennas, with further outdoor field tests planned. DL7JV also intends to build a 1.8 MHz version.

The Icom IC-7300 is a popular SDR transceiver known for its excellent performance in ham bands. However, users have reported issues with reception reliability outside these bands due to ADC aliasing. This phenomenon occurs when the sampling rate of the radio interacts with frequencies outside the intended range, leading to unwanted signals being received. For instance, when tuned between 30 to 36 MHz, users may inadvertently pick up WFM broadcast signals or PMR communications due to aliasing effects. This guide outlines modifications to improve the IC-7300's performance by addressing the low-pass filter design, which is crucial for reducing interference from these unwanted signals. The proposed modifications involve adjusting the low-pass filter on the PA unit to better attenuate frequencies that cause aliasing. Measurements indicate that the original filter design allows significant signal leakage, leading to false receptions. By implementing the suggested changes, users can achieve a notable reduction in unwanted signals, enhancing the overall functionality of the IC-7300. While the modification requires careful soldering, the benefits in performance make it a worthwhile endeavor for serious operators looking to optimize their SDR experience.

Custom cases and stock cases

SimpleHRR is a free ham radio remote control web application (or web app) hosted by Raspberry Pi in the ham station to remote control a ham radio HF transceiver through a supported web browser from a Desktop PC, Laptop or Android phone. Supports recent ICOM IC-7x series transceivers

Ham radio, amateur radio, satellite communication, radio, radios,antenna, antenna design, yagi, cross yagi, power divider, splitter, Brisbane.

This article discusses how volume reduction can help in the reception of weak signals by reducing the noise level. It is commonly known that reducing the volume also reduces the background noise, and especially in the reception of weak digital signals it can be beneficial

Republic of Niger 2017 5U5R DXpedition web site 2017 Mar 9 - 2017 Mar 2 Will operate 160 to 10m, also 5.360 MHz; SSB CW RTTY; QSL via EA5RM

eHam reviews of the Icom IC R7100 VHF UHF receiver

The official club site of K7UAZ.

All available frequencies & offsets configurations for repeaters can be downloaded as database for Kenwood MCP-2A memory channel programming software for TM-D710 & TM-V71. Zip file is no more available from the author, but the full table of frequencies is still online

Design and manufacture antennas for mobile devices, wireless data including WiMAX, WiFi, and WISP (Wireless Internet), two-way radio and RFID (Radio Frequency Identification).

Sponsored by The Columbia Amateur Radio Club

TRS RenTelco provides new or used electronic test equipment for rent, lease or purchase. Solutions are provided for various type of equipment such as spectrum analyzers, network analyzers, oscilloscopes etc from leading manufacturers. Our products are widely used in communications, R&D, semiconductor, and wireless industries.

10 Elements Cross-Yagi Antenna for 433 MHz. The base of the 10el antenna is the recalculated RA6FOO antenna.Circular polarization is realized - by a phasing quarter-wave line, matching of horizontal and vertical polarization antennas

A distance of 1/8 lambda between the antenna and the vehicle roof is suggested for optimal performance, with slight adjustments possible to lower the take-off angle for terrestrial contacts. This resource details the adaptation of an _Eggbeater_ antenna for mobile use, specifically for VHF operation, leveraging the car's metal roof as a ground plane. It illustrates the mounting method, repurposing a magnetic ski carrier base, and describes the integration of coaxial relays for polarization reversal, a feature also applicable to UHF versions as discussed in "_Eggbeater Antenna VHF/UHF – Part 2_". This mobile configuration proves effective for satellite communications, such as through the International Space Station (ISS), while also maintaining strong performance for land-based radio contacts. The inclusion of switches with indicator lights for VHF and UHF polarization control, powered by the vehicle's battery, highlights practical considerations for field deployment. The system's adaptability for portable operations underscores its versatility beyond fixed mobile installations.

Reviews of the Icom ID-51A handheld dual band transceiver

Kay County Amateur Radio Club Incorporated in the State of Oklahoma Jan. 1960 W5HZZ

Jeri Ellsworthhas started a video series devoted to building a magnetic loop antenna for the 160- and 80-meter bands. The first video, included after the break, is an overview of the rationale behind a magnetic loop

Turning an RV marine battery into a massive 12-volt emergency power source

GREENSTONE USA leader in the Vacuum Industry manufacturing products such as Vacuum Tubes, Vacuum Capacitor, Vacuum Relays, Vacuum Contactors and Vacuum Interrupters.

International postage stamps by K3FN

E51LYC DXPedition to Pukapuka atoll OC-098 North Cook Isl 2017

Tips on QSLing. Once you work that DX station, you have won the battle, but the war may just be beginning. I am talking about getting the QSL card. There are several ways to go about this.

OY/DL3UB , Faroe Islands (29. July - 09. August) verticals + PA (max 500w) WARC bands cw

PT0S DX pedition Nov 10 to Nov 22 , 2012

The Texas Slow Net (TSN) operates daily at 7:45 PM local time on 3570 KHz, serving as a dedicated traffic handling training net within the National Traffic System. It specifically caters to operators aiming to enhance their **International Morse Code** skills and learn proper CW traffic net procedures. Each session incorporates a traffic handling lesson delivered as a radiogram to all participants, reinforcing practical application. The resource provides guidance on effective Morse Code learning, emphasizing sound recognition over visual dot/dash counting, suggesting characters be sent at 15 words per minute with adjusted spacing. It recommends listening to W1AW code practice transmissions, setting goals with ARRL's Code Proficiency Program qualifying runs, and regular participation in NTS traffic nets. The content also references the ARRL's Public Service Communications Manual, particularly Section 2, which details the **National Traffic System**.

If your club holds only two-meter ARDF events, you are missing half the fun. There is another international foxhunting band, too.

The page automatically generate a Great Circle Map (GCM) for ham radio operators based on the IP address or by a given QTH locator. The GCM generated, unlike traditional maps of this type, has been rendered in an elliptical shape instead of a circle. This provides an expanded view horizontally thus making it easier to interpret. The map base is colored with each continent colored differently for easier recognition. The color code of the continents is given below the map for easy reference

A detailed review of the Icom IC-7700 by VA7OJ/AB4OJ

Amateur radio news, events and other electronic stuff by KE2YK

Ham radio blog by KU7PDX Chris Arnesen

Microwaves101 provides an extensive repository of information covering fundamental principles of microwave design, targeting engineers and radio amateurs interested in the higher frequency spectrum. The site features a detailed _encyclopedia_ of microwave terms and concepts, alongside practical design considerations for various components and systems. It serves as a foundational reference for understanding RF propagation, transmission lines, and active/passive microwave circuits. The resource includes numerous calculators for impedance matching, filter design, and other critical RF parameters, facilitating hands-on project development. Discussions on **10 GHz** equipment and **24 GHz** projects highlight practical amateur radio applications, extending to operations up to 134 GHz. Content spans from basic theory to advanced topics like MMIC design and antenna characteristics, supporting both educational and practical endeavors in microwave technology.

The Spectrum Monitor, amateur, shortwave AM FM TV Scanning Satellite magazine, is edited and published by Ken Reitz KS4ZR, former managing editor, features editor, columnist and feature writer for Monitoring Times.

YT9X Serbja contest team

Testing a Bencher YA-1 low-pass TVI filter with a spectrum analyzer with tracking generator.

This PDF document reviews the POTA PERformer Antenna by KJ6ER, providing insights and details about its performance and features. The content is aimed at hams looking for information on this specific antenna model to help them make an informed purchasing decision. It contains technical specifications, user experiences, and possibly recommendations for optimal use. The review is valuable for hams interested in portable operation and seeking a reliable antenna solution for Parks on the Air (POTA) activations.

Mali DX Pedition by Italian DXPedition Team 2012

This blog article introduces an updated repeater controller project utilizing the Arduino UNO. It includes a CW identifier, and the ID message can be customized using hex codes. The author offers a Windows command line program for easier message coding and provides a link for download. The controller features three adjustable timers for IDer, Timer-out, and Squelch-tail. The article also mentions the use of an audio switch to control audio levels between the receiver and transmitter. Detailed instructions and code files are available on the author's website for both version 1 and version 2 of the Arduino repeater controller. The project aims to enhance repeater functionality and audio management in ham radio operations.

Showcasing college amateur radio club activities, events, and projects. Informs visitors of up to date news items pertaining to ham radio technology used on campuses by students, faculty, and staff. A way for alumni to be informed of their clubs activities.

Installation and modification of the popular Butternut HF9V antenna with the optional 160 meter addon. Article includes a modification to improve the performance on the top band

Useful Function for the Drake TR-7(A) \"Store\" Switch Add A Transmit Key Function

VP8STI log on line VP8 DX Pedition