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Understanding Gain differences, j-pole and end-feed vertical antennas.

RigPix Database picture of the TS-850

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

Consoles, Recorders, Dispatch, Alerting, Paging, Monitoring equipment.

Why twinlead isn't necessarily a low loss feed line.

Sounds of Space Weather by S. McGreevy, N6NKS

Radio Scanning in Australia

Build An Inexpensive Repeater Controller from a Basic Stamp 1 or 2 By Roger Cameron

Custom iambic paddles by N3ZN

Adventures in amplified GPS antenna construction; an experiment

Ham Radio repair of all major brands and models, located in Carrollton, Texas, which is just north of Dallas, and have been serving the Amateur Radio community for over 20 years.

This is a design for a stealthy HF multi-band vertical wire antenna using a tree as a supportby G7AQK

136kHz portable station project by PA4VHF Dick

This document contains the detailed instructions to build a homemade lindenblad antenna using a twin-lead as dipole elements. This document contains 9 pages and includes a detailed construction sequence and some drawings to build this antenna for UHF and VHF ham radio bands

A group dedicated to the HF Kenwood Transceiver TS-590 S

A flex antenna working on 6m and 70cm by K0EMT

Setting up a Raspberry Pi as Remote Server for RTL2832u SDR

This online guide details the microphone pinout for the Kenwood TR-7950 transceiver, specifically addressing the wiring configuration for a dynamic mobile microphone with a **500 Ohm** impedance. It provides a pin-by-pin breakdown for the 6-pin microphone connector, identifying the function of each active pin. The resource specifies that Pin #1 is for the microphone audio (white wire), Pin #2 controls the _PTT_ (black wire), Pin #3 activates the memory down function (blue wire), and Pin #4 controls the memory up function (red wire). Pin #6 is designated as the ground connection, while Pin #5 remains unused in this configuration. The document focuses on the physical wiring necessary to restore microphone functionality to the Kenwood TR-7950, a transceiver capable of **45 watts** output on the _2m band_. It directly addresses the technical challenge of re-establishing correct electrical connections after microphone wires have been disconnected from the connector. The information facilitates proper microphone operation for simplex QSOs and other voice communications. DXZone Focus: Online Guide | Microphone Pinout | Kenwood TR-7950 | PTT Wiring

Cheap UHF antenna plans for 2 meters and up including 421 1296 and 902 Mhz

Ham Start, starter kit. Stugy guides, resources, exams, upgrades and morse code. A guide for beginners and license upgraders, Resources for getting started and advancing in ham radio (USA)

Homebrewing a mic boom headset for the Yaesu FT 897 and 857 transceivers

Towers by Tashjian, Engineering, Design and Manufacturing

RTL-SDR is a very cheap software defined radio that uses a DVB-T TV tuner dongle based on the RTL2832U chipset. This is a blog about rtl-sdr, software defined radio and their developments and applications.

The Top-Rated Electrical and Electronic Engineering Calculator for Palm OS

2,6 and 10 meters beacon located at Lake White, Ohio

TX3A online log for Chesterfield Islands 2009

The G5RV multiband HF antenna, designed by Louis Varney (G5RV) in 1946, is a popular compromise antenna offering good overall performance on most HF bands when paired with an external antenna tuner. The basic full-size G5RV measures 102 feet across the top for 80 through 10 meter operation and is fed at the center via a 34-foot low-loss feed-stub. This interaction between the radiating section and the feed-stub facilitates matching across 80-10 meters with a standard tuner, often eliminating the need for ladder line directly to the shack. The antenna's design center frequency is 14.150 MHz, configured as a 3/2-wave dipole on 20 meters, with its 102-foot length derived from long-wire antenna formulas. Construction details emphasize the matching section, which can be open wire, ladder line (window-type), or TV twin lead. Each type has a specific velocity factor (VF) affecting its physical length for an electrical half-wave on 14 MHz; for instance, open wire requires 33.7 feet (VF 0.97), ladder line 31.3 feet (VF 0.90), and TV twin lead 28.5 feet (VF 0.82). The article provides formulas for calculating these lengths and discusses the antenna's behavior on individual bands, from 3.5 MHz where it acts as a shortened dipole, to 28 MHz where it functions as two three-half-wave long-wire antennas fed in-phase. Practical construction notes include recommendations for vertical descent of the matching section, sealing the coax junction, providing strain relief, and winding a coaxial choke coil to mitigate common mode current. The resource also presents dimensions for double-size (204 ft) and half-size (51 ft) G5RV versions, along with their corresponding matching section lengths for various line types, making it a versatile reference for hams considering this classic wire antenna.

Make your own interface, two schematics for building an interface using the RTS line by N3UR

FT-817 compared to FT-100 and review

The Quick and Dirty unofficial Help File for Nino IZ8BLY's Chip 64 Software

Calculating Antenna Wind Load

IC820H or other Icom Radios Soundcard interface for VHF EME use by DF9CY

Article on a 2 and 6 meters halo antennas that does not require a mast has a very low part count and can easily be built with a minimum of tools.

Presents a collection of articles and project logs from ST2NH, focusing on various aspects of amateur radio, including satellite communications and DIY electronics. The blog details experiences with tracking the _International Space Station_ (ISS) and other orbital assets, providing insights into the operational challenges and successes encountered in these specialized modes. Documents several homebrew radio projects, offering construction details and discussions on circuit design for various amateur radio applications. Content often touches upon software-defined radio (SDR) implementations and related software tools, demonstrating practical applications for hams interested in digital signal processing and flexible radio architectures. Explores topics relevant to QRP operation and general amateur radio news, reflecting the author's engagement with the broader ham community. The blog serves as a personal chronicle of amateur radio activities and technical explorations.

Article on various type of transmissium medium, like parallel lines, twisted pairs, shielded pairs, coax lines

HB9DNU Karlheinz's blog, hosted on Blogger, presents a collection of personal reflections and observations, predominantly in German. The content spans various non-amateur radio subjects, including Swiss political initiatives, economic discussions concerning banks like UBS, and social commentary. For instance, an entry from February 2008 details the Swiss vote on a combat jet noise initiative, highlighting the debate between tourism concerns and national security. Another post from October 2008 critiques the 500 billion Euro bailout package for banks, calculating its per-capita cost for German citizens and referencing earlier blog entries from March 2006 and June 2007 that discussed UBS salaries and Raiffeisenbank issues. These entries often reflect Karlheinz's personal perspective on current events. The blog also includes lighter, more personal notes, such as a February 2009 entry about a video produced by his grandson, and observations on local events like a bird exhibition in Contone or a scenic train ride through the Centovalli, demonstrating a broad range of interests beyond the ham radio hobby.

A Low -Power Indoor Portable HF Antenna by Monty Northrup, by N5ESE

An active receiving antenna for 10 KHz to 20 MHz, a very small sized antenna with excellent performances in noise to signal ratio.

If your doing any home brewing gear for ham radio its a great idea to have a dummy load. This will to your radio be the perfect antenna...it will never radiate but your radio sees a perfect 50 Ohm impedance.

The resource presents a mobile antenna mast mount designed for rapid deployment from a vehicle's trailer hitch, addressing specific design criteria for portability and ease of use. It outlines seven key design goals, including fitting inside a vehicle, handling various mast diameters, and enabling one-person setup without tools. The construction utilizes offset T-handled stainless bolts for tool-free mast securing and a "tab" mechanism to prevent collar slippage. Detailed deployment instructions are provided, covering steps from attaching the bottom collar to securing the mount in the hitch, erecting the mast, and tightening both collars. The author, K0EMT, reflects on potential improvements, such as welding the bottom collar for enhanced stability versus transportability. The project also credits AA0ZC for the physical construction.

A 50-ohm 10W resistor forms the core of this portable QRP antenna, designed by _K0EMT_ for convenient operation on 160m and 80m. The construction involves soldering the resistor to a BNC connector, with one lead to ground and the other to the center conductor, then insulating the assembly. This minimalist design aims to provide a highly portable solution for low-band QRP operations, acknowledging the inherent trade-offs between antenna size and efficiency. Testing with an antenna analyzer revealed low SWR on both 160m and 80m, with a Yaesu FT-817 confirming good matching. While 40m and 30m showed higher SWR, the primary focus remains on the lower bands. The author successfully tested the antenna with **2.5W CW** output, demonstrating its practical application for QRP field operations where ease of deployment is paramount, even if it means sacrificing some **gain** compared to full-sized antennas.

2 meter kilowatt linear amplifier

1:1 Ruthroff voltage balun using a T200-2 Toroid core

Spanish ham radio shop with a complete amateur radio equipment offer

Homebrew a compact yagi antenna for 14 Mhz suitable for those with small plots based on a design by AB4GX

allows a Macintosh computer to communicate via packet radio with the amateur packet satellites currently in operation using the 'PACSAT' protocols

Eham IC-2100H review

This program expedites the design of lumped-element diplexers using both the lowpass/highpass and the bandpass/bandstop topologies.

Mobile antenna placement presents unique challenges for the amateur radio operator, often requiring compromises between RF performance and mechanical considerations. This resource from KV5R.COM offers practical insights into achieving effective installations, drawing on real-world experience with different vehicle types. It details how factors like ground plane availability, proximity to vehicle structures, and antenna type (e.g., **HF mobile**, **VHF/UHF mobile**) influence signal radiation patterns and overall system efficiency. The author discusses common scenarios, from sedans and SUVs to trucks and RVs, highlighting the impact of mounting locations such as the trunk lip, fender, or roof. Specific attention is given to minimizing RF interference and maximizing radiated power, crucial for reliable mobile communications. Understanding the interaction between the antenna and the vehicle's metallic body is key to a successful mobile setup, and this content provides a solid foundation for making informed decisions.