73 Amateur Radio Today

Magazine Overview

Title: 73 Amateur Radio Today
Issue: #435
Date: December 1996
Publisher: 73 Amateur Radio Today
Country: USA
Price: $3.95 USA / $4.95 CANADA
Cover Headline: Be A Key Person Internet Hamming

This issue of 73 Amateur Radio Today, dated December 1996, focuses on a variety of amateur radio topics, including a significant high-altitude balloon mission, advancements in amateur television (ATV), and new technologies for 'Internet Hamming.' The cover art depicts a festive Christmas scene with handheld radios in stockings, hinting at holiday-themed content or a general seasonal issue.

High Altitude Balloon Mission

The lead story details a high-altitude balloon mission conducted by a group called HALO (High Altitude Lift Off) on September 22nd. The objective was to test a payload designed for a future 'rockoon' – a rocket launched from a balloon platform at 90,000 feet, intended to briefly enter space. The payload included a nitrous oxide fuel tank with pressure and temperature probes to study the effects of the balloon flight, crucial for firing a hybrid rocket. The experiment payload also featured an ATV/telemetry system built by Ed Myszka KE4ROC, comprising a live color TV camera, a PC Electronics KPA-5 ATV transmitter on 434 MHz, a microphone, a big wheel antenna, and a sensor decode system with two Basic Stamp IIs hooked to a GPS/Pico-Packet combo. Telemetry and position information were transmitted in APRS format on 145.79 MHz. The payload was housed in a sturdy aluminum frame covered with Styrofoam for thermal insulation.

The launch took place at an old airport in Huntsville, Alabama, under near-perfect conditions. A 19k cu.ft. Raven zero pressure balloon was used, which is designed to vent helium and level off at altitude rather than burst. During the launch preparation, the balloon was accidentally snagged by a gust of wind, causing two large holes in its side. These were taped shut, and the launch proceeded. The balloon ascended at a leisurely pace, described by Bill Brown WB8ELK as "just like taking an elevator to the edge of space." The ATV camera provided a clear view of the ground below. However, at 39,000 feet, the balloon began to descend slowly, indicating that the taped holes had sprung leaks and were releasing helium.

To allow the system to land closer to potential recovery teams, the cutdown mechanism was not fired. The payload descended slowly, and a chase team, organized by Ralph Fowler N4NEQ, tracked its position using an APRS system. After traveling 108 miles, the balloon landed at 1:59 p.m. in a kudzu patch southwest of Dallas, Georgia. The owner of the property, seeing the balloon land, initially thought it was a UFO and contacted local media. The payload survived the landing and was recovered.

Post-flight analysis revealed valuable data, and the flight was considered a success. The article emphasizes the need for extensive planning, coordination with the FAA, and obtaining launch permissions for such missions. Bill Brown WB8ELK shares more details and photos on his personal website.

Amateur Television (ATV) and Other Technologies

The issue also delves into Amateur Television (ATV), promoting the TVC-4G ATV 420-450 MHz downconverter, priced at $89. It highlights how ATV repeaters and individuals are retransmitting Space Shuttle video and audio, as well as home camcorder footage. The article encourages readers to get involved in ATV and mentions the availability of other ATV equipment such as downconverters, antennas, transmitters, and amplifiers for 400, 900, and 1200 MHz bands. P.C. Electronics is presented as a one-stop shop for ATV needs.

Another section discusses 'Packet Track,' a 'Stealth Attic Antenna,' and the 'JBI Interface Kit,' suggesting practical projects and equipment for radio amateurs. The magazine also features advertisements for Pauldon Associates, offering power amplifiers and preamplifiers for AM & FM frequencies, as well as ATV transmitters and transceivers.

Recurring Themes and Editorial Stance

This issue of 73 Amateur Radio Today showcases the magazine's commitment to covering cutting-edge amateur radio technology and experimental projects. The editorial stance appears to be one of encouraging innovation, exploration, and hands-on involvement in diverse areas of the hobby, from high-altitude rocketry and ballooning to ATV and digital communications. The inclusion of detailed project descriptions, technical specifications, and contact information for suppliers reinforces a practical, DIY-oriented approach. The magazine aims to inform and inspire its readership by presenting both ambitious scientific endeavors and accessible technical projects, all within the framework of amateur radio.