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Spitfire Collinear Arrays for 160 meters band at UA2FW

FP/KV1J July 2014 DXpedition to Miquelon

A tutorial on how to get started operating RTTY using MMTTY as the primary program to begin your RTTY operations. Installing, configuring and using MMTTY. Documentation in English and Spanish

T30 BY SP5EAQ SP5DRH, West Kiribati 2011

Yamuna Cable Accessories Pvt. Ltd. specializes in the development, manufacturing, and marketing of power cable accessories, including a comprehensive range of cable jointing kits and components. The product line encompasses _Heat Shrink_ and _Cold Shrink_ cable joints, heat shrinkable tubing, pre-moulded slip-on joints, resin pour, and Tapex systems, all designed for applications up to 66 kV. The company highlights its ISO 9001-2015 certification, signifying adherence to international quality management standards in its manufacturing processes. The resource details specific product categories such as end caps, insulation piercing connectors, copper mesh, fireproof coatings, tubing and components, lugs and ferrules, and safety products. It also features specialized items like _Elbow Connectors_ rated for 25 kV-250, 400, and 630 amps, and various types of tinned copper braid used for grounding and electrical shielding. The site provides an overview of their manufacturing capabilities and global presence across 40+ countries. Established in 1973, Yamuna Densons has over four decades of experience in the industry, positioning itself as a significant designer, manufacturer, and supplier of insulators, tabs, and cable jointing systems in India. The company emphasizes its role as a leading exporter of these products, serving both domestic and international clients.

An explanation of the different procedures and definitions that are commonly used for blocking dynamic range (BDR) measurements. Dynamic range in general is the ratio between the weakest signal a system can handle and the strongest signal the same system can handle simultaneously without an operator switching attenuators or turning volume potentiometers

Asociacion de radioaficionados rocieros

The antenna ground or earth system can be key to its operation whilst also being a key safety feature. This article is about grounding systems for antennas, covering different aspects of grounds made for antenna safety, or expressly for lightning or just to improve antenna performance, being ground an antenna component.

Iraqi amateur radio society

Tubes and electronic components online shop. Dealer for svetlana, sovtek, tesla, mullard and tungsol tubes

Personal web site of VE2WPT Nick from Montreal Canada

A windows program to learn Morse code and doing QSO in CW. The training course contains 39 Lessons based on Koch method. It can sends only letters, only numbers, only punctuation

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

Icom IC-R75 product page at SWling.com with technical details and links

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

4S7 Log Online Sri Lanka DX Pedition - March 2014

Operating on Airplane scattering. Scattering of radio signals by airplanes. An introduction to operating ariplane scattering, using aircraft to redirect RF that would otherwise be lost in space. Antenna Pointing, Doppler Shift/Digital Modes, using digital modes to operate airscatter.

I used a FT 240-43 for much more power, not needed but beter safe than sorry. 150 Watt continious, 300 Watt PEP SSB, 90 Watt Digimodes 10 Mhz, 18 Mhz, 24 Mhz Very easy to build design and a good antenna for people who don't have much space for big towers or long wires This design is from Hans - PE1RNU

I wanted to mount an amateur radio antenna on my truck that was more permanent than the magnetic mount on I already had, but I had a few specific design requirements for the project.

High-performance rugged antennas and RF accessories such as magnetic mounts, RF coaxial gooseneck adapters, LNAs, BDCs, for law enforcment, military, maritime and video markets.

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.

The K3NG Keyer is an open source Arduino based CW (Morse Code) keyer with a lot of features and flexibility, rivaling commercial keyers which often cost significantly more.

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

Covers the WB2JKJ Educom HF Net, which operates on 7.238 MHz and 21.395 MHz. This resource highlights the activities of The Radio Club of Junior High School 22 NYC, Inc., a non-profit organization established in 1980. The club's mission, "Education Thru Communication" (EDUCOM), focuses on integrating amateur radio into schools across the nation as a teaching theme. WB2JKJ, Joe Fairclough, founded and presides over this club, which is recognized as NYC's largest ham radio club. The site also provides access to the "APPLE SLICE NewsletterCurrent Edition" and information on how to support the organization. It includes a scrapbook section and contact details for further engagement. The content was last updated on May 5, 2023, reflecting recent activity.

Marscomponents is an independent distributor of electronic components. Offer one-stop sourcing service for ICs, connectors, discretes, transistors and other electronic components and devices

McMinn County Amateur Radio Club, Inc. in Athens, TN.

This morse key and buzzer design only requires parts that one may already have or are easy to find on the web. There is nothing critical except that the contacts must meet when the key is depressed.

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

An inductance and capacitance meter, measuring range is from 0 to >0.1uF for capacitance and 0 to >10mH for inductance. A project by Phil Rice, VK3BHR

Elecraft new QRP transceiver, an 80-10 m SSB/CW/Data station that fits in your pocket

This page is devoted to the state of Maryland. It contains links for Trunktracker information and conventional data, along with amateur radio sites

Ohio Area Repeater Council

An end fed antenna winder design that also contains the necessary matching toroid. This would be just the thing to throw in your backpack for portable operation.

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

With over 1700 members CARMA is the largest scanner club in the USA. We support all facets of public safety and promote responsible radio monitoring.

Constructing a dual-band antenna for 40 and 20 meters often involves compromises in size or complexity. This resource presents a compact _open sleeve dipole_ design that addresses these challenges by using 450-ohm ladder line and folded elements to achieve a total length of approximately **17.17 meters**, significantly shorter than a full-size 40-meter dipole. The design leverages electromagnetic coupling, where a primary radiator handles the 40-meter band, and a second conductor resonates on 20 meters without direct electrical connection. This configuration eliminates the need for traditional traps, loading coils, or switching components, simplifying construction and reducing potential loss points. The antenna is fed with RG-58C/U coaxial cable, and a common-mode choke is recommended at the feed point to suppress sheath currents, ensuring a cleaner radiation pattern and minimizing RF in the shack. The design is well-suited for portable operations, field deployments, temporary installations, and restricted urban environments where space is a premium, offering solid performance on both HF bands.

eHam.net reviews of the Icom IC-R20 wideband receiver

eHam users review of the Icom IC-R75 receiver

March 2015 9Q0HQ Congo DX pedition

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.

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

Antennas custom made to your frequency of choice

Tutorial- WSPR receiver with Raspberry Pi and RTL-SDR

The Carolina Amateur Radio Club is a service-oriented club and has been in existence for more than 30 years

Official web site of the Youngsters On The Air Italy 2015

How to solve RFI problems caused by the charge controller, which is a PWM type charge controller, that generates a lot of EMI interference

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

PT0S DX pedition Nov 10 to Nov 22 , 2012