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SSTV Fundamentals, frequencies in use for SSTV and many SSTV related infos, includes Fax basics

Announce your callsign at least once every ten minutes. HamTime runs in the corner of the screen and gives you an audible alarm when that announcement is due.

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

Offer a wide range of homebrewing projects mainly for VHF UHF operations. From vhf antennas to preamplifiers, chargers and power supplies

How to adjust your SWR on your radio and why.

Covers experimental work from VLF through laser by K3PGP, one of the EME pioneers.

The configuration of this antenna is a triangle with apex in the top of a very tall tree. The antenna is fed at a bottom corner using 450 ohm ladder line.

A Chaotic Collection of Keys, Paddles, and Bugs

Located in the northeastern corner of New York State Between the shores of Lake Champlain and the foot hills of the Adirondacks

For over 50 years, Communications Specialists Inc. has been a cornerstone in specialized radio frequency solutions, initially gaining prominence with their **CTCSS** and **DTMF** tone signaling products widely used in amateur radio repeaters and commercial two-way radio systems. My own experience with their tone boards in various repeater builds confirms their reliability and ease of integration, a testament to their engineering. The company's legacy in tone encoding and decoding is well-established, providing robust solutions for access control and selective calling. Beyond tone signaling, Com-Spec has diversified into niche markets, including wildlife telemetry, pet tracking collars, and specialized tracking systems for model aircraft and rocketry. Their product line features compact transmitters and receivers designed for specific tracking applications, demonstrating a commitment to precision and durability in challenging environments. While some legacy products are no longer available, Com-Spec continues to innovate, as evidenced by the new R-30M receiver, which ships within five days. This focus on specialized RF applications, from tracking Alzheimer's patients to law enforcement, highlights their unique position in the radio communications industry.

Since the beginning when a small group of Hams met to form a club in the southwest corner of Dallas County, it has always been known as SWDCARC or by it's full name, Southwest Dallas County Amateur Radio Club.

Presents the Carolina DX Association's (CDXA) _Contest Corner_, a dedicated resource for amateur radio contesting activities. It features a curated contest calendar, linking to external resources such as the _WA7BNM Contest Calendar_ and the _ARRL Contest Calendar_, providing a broad overview of upcoming events. The page also details CDXA's internal contest programs, including the "CDXA DX King" and "CDXA DX King Classic" for 2026, with specific links for members to submit their scores. Furthermore, the resource integrates with _3830Scores.com_, encouraging CDXA members to submit their contest results and select the club affiliation for tracking. It provides a direct link to view aggregated scores from participating CDXA members, fostering club competition and recognition. The "CDXA Periodic Table of Contest - 2026" is also mentioned, indicating a structured approach to contest planning for the year.

Active antennas can be very useful, in particular they can help reduce local electrical noise by allowing the antenna to be installed in a corner of the garden well away from house wiring. The original PA0RDT antenna uses a very small patch for the antenna and relies on the antenna being installed quite high.

Corner Press full service printing since 1971 & QSL's SINCE 1961, founded as The WA2WAO Press. Made in USA

Just my little corner of the world, one radio at a time

Author found a ratio between the lengths of the sides of the Delta Loop that give reasonably low SWR into a 50 ohm coaxial cable almost independent of the high above ground and other surroundings. This ratio also gives good results no matter orientation. Includes an online delta loop antenna calculator.

This 160 meter Delta Loop antenna is made of Hard drawn copper wire AWG 10, the two upper side are 148.5 foot each base wire is 240.9 foot, the feed point at 30.69 foot to one corner, feed with 450 Homs balanced line to an antenna tuner on the ground, then with 50 homs coax to the shack.

This project involves constructing a dual-band Moxon antenna, optimized for ham radio enthusiasts, with functionality on both the 10-meter and 6-meter bands. The antenna is designed to operate using a single 50-ohm feedpoint, acting as a mini-beam on 28 MHz (10 meters) and as a 2-element Yagi on 50 MHz (6 meters). Performance-wise, it offers a 4.0 dBd gain on 10 meters and 4.3 dBd on 6 meters, with impressive front-to-back ratios of 30 dB and 11 dB, respectively. Builders like Aleks (S54S) and Marcio (PY2OK) have successfully brought this design to life using the provided specifications. Aleks noted that bending the corners of the structure proved especially useful during assembly. The project comes with a detailed parts list, highlighting the use of aluminum tubes with different diameters and lengths to form essential components like the reflectors and radiators. For those looking to fine-tune the antenna, adjustments can be made by altering the length of certain parts that fit into larger tubes. The feeding system is equipped with a balun to accommodate different power levels, making the design versatile enough to handle outputs of either 300 watts or 1 kilowatt.

This project explores the construction and performance of an Alford Loop antenna as an alternative to a round loop. The Alford Loop, symmetrically fed at opposite corners, behaves like a small loop despite its larger size. Built using PVC pipes and secured with tire wraps, the antenna integrates an LZ1AQ active amplifier for optimal performance. With deep nulls in its horizontal radiation pattern and improved resonance characteristics, this design has significantly outperformed previous active antennas in reception quality.