1997 02 00 73 Magazine - Colombia

Magazine Overview

Title: 73 Amateur Radio Today
Issue: #437
Date: February 1997
Publisher: 73 Amateur Radio Today
Country: USA
Price: USA $3.95, CANADA $4.95

This issue of 73 Amateur Radio Today, the International Edition, prominently features "Software Home-brewing" with a lead-in to page 10. The cover showcases a large, complex antenna array against a winter landscape, hinting at advanced amateur radio projects.

Key Articles and Projects

Software Home-Brewing The issue delves into software home-brewing, presenting several DIY projects for enthusiasts. These include:

• Beam-aimer: A device likely for directional antenna control.
• Turbo Digi-sniffer: A tool for digital signal analysis.
• Gel Cell Charger: A charger for gel cell batteries, common in portable radio setups.
• 160m Antenna Tuner: A tuner for the 160-meter amateur radio band.
• Stealth Antennas: Antennas designed for discreet installation.

Technical Deep Dives

• Retuning Microstrip Amplifiers: An article details how to retune 14-14.5 GHz power amplifiers for use on the 10 GHz amateur band. It outlines a tuning procedure involving tuning wands and stubs, emphasizing careful measurement and adjustment to maximize output power without damaging components like FETs. Additional notes stress the importance of direct grounding for microwave power devices and proper board mounting to prevent oscillation.
• LM386 Amplifier Issues: Common problems with LM386 audio amplifiers, such as "motorboating" (oscillation), are addressed. Solutions include increasing the value of the decoupling capacitor on the VCC line and, in stubborn cases, inserting a small resistor in series with the VCC line. The article also highlights the importance of a well-regulated power source, noting that a standard 7812 regulator might not provide sufficient overhead for the LM386, and suggests alternative voltage regulator configurations or direct powering from a 12-14V supply.

Reviews

The magazine includes reviews of new amateur radio equipment:

• Ten-Tec 6m Transverter: A review of a transverter for the 6-meter band.
• Hamtronics RWX: A review of another piece of ham radio hardware.

Reader Contributions and Letters

UFO Encounters Several readers share their experiences and thoughts on UFOs:

• Colombian Encounters: A reader recounts a Turkish Air Force officer's encounter with a UFO while flying an F-104, which caused the aircraft to veer away. Another account involves a Colombian Navy frigate's encounter off the coast. A DLIELC instructor also shares that Colombian military officers, particularly those at the highest levels, have been briefed on extraterrestrial visitors.
• New Jersey Sighting: A personal anecdote describes hearing unusual noise from a snowplow three miles away, attributed to its alternator, and observing a puff of smoke. The same individual also recalls weird noise resembling a mishmash of signals when pointing an antenna towards abandoned Edison mines.
• Francestown, NH Crop Circles: A farmer reported a UFO hovering over his house, which was later corroborated by staff at the Crotched Mountain Rehabilitation Center.
• General UFO Discussion: Cliff Gieseke W4ZFL expresses fascination with UFOs since the 1950s and notes that a high-security consultant to President Clinton indicated that ETs are already here, with his son in Annapolis reporting that upper-class students are being taught this.

Ham Radio Experiences

• Ground-Wave QSOs: A reader reminisces about ground-wave QSOs with New York City/Long Island hams and working 15-meter ground-wave stations up to 200 miles away, even receiving calls from South Africa.
• Selling Music Systems: A suggestion is made for making a living by selling audio systems to restaurants, complete with CD players and appropriate ethnic music.

Technical Support and Advice

• Power Supply Regulation: Advice is given on using voltage regulators for the LM386, suggesting alternatives like a 7810 or 7808 if the primary supply voltage is between 12-14V, or using diodes or resistors to raise the ground pin for increased output voltage. The importance of specifying the correct regulator for the circuit is emphasized.
• Schematics: The author apologizes for missing schematics in the previous month's column due to a move and provides a new mailing address for requests.
• Solar Home Project: A reader mentions plans to construct a 100 percent solar home with a 4 kW peak solar array and a 65-foot tower, timed with the expected increase in the sunspot cycle.

Special Events and Advertisements

The issue lists several upcoming ham radio Special Events in February, including:

• February 8: Charleston Hamfest and Computer Show, Charleston, SC.
• February 9: Mansfield Mid-Winter Hamfest/Computer Show, Mansfield, OH.
• February 13 & 27: VE Exams in Fort Worth, TX.
• February 14-16: Orlando HamCation and Computer Show, Orlando, FL.

Advertisements feature:

• The Preferred Full Half Duplex Autopatch: A device for amateur radio communication, priced at $109.00.
• Ultimate plus Pocket Morse Code Trainer: A portable device for learning Morse code, priced at $69.99.
• Deluxe Plus Pocket Morse Code Trainers: A similar device, priced at $44.99.
• Standard Plus Pocket Morse Code Trainers: Another version, priced at $29.99.
• EMAC, inc. PRIMER 8085 Based Microprocessor Training and Control System: Available in kit form for $119.95 or assembled for $169.95.
• MultiMode TNC BayPac: Packet modems, including the BP-2 Packet Only ($49.95) and BP-2M MultiMode ($69.95).

Recurring Themes and Editorial Stance

The magazine consistently promotes "home-brewing" and DIY projects within the amateur radio community, encouraging readers to build and experiment with their own equipment. There's a strong emphasis on practical application and problem-solving, as seen in the technical articles on amplifier tuning and troubleshooting. The inclusion of UFO accounts and personal anecdotes suggests an editorial stance that is open to a wide range of topics of interest to its readership, beyond just the technical aspects of radio. The "Never Say Die" column, in particular, often touches on broader societal issues and personal philosophies, reflecting a thoughtful and sometimes unconventional perspective.