Improved Mechanical Design for the Helical Antenna

2822 Woodside Drive Quincy, IL 62301 The helical antenna is an effective way to obtain circular polarization, but the wooden mechanical design of the antenna as typically used by amateurs leaves something to be desired. In this article, an almost all-metal mechanical structure is presented. It can be made from readily available material and can be built with common hand tools. The helical antenna is a widely used satellite antenna in the amateur community as well as in the professional world....

Info

3 The ARRL Antenna Book, Chapter 19, pp 22-23. 'Kraus, J.D, Antennas, New York McGraw-Hill, 1950, Ch 7. 'Wong, J.L. and King, H E., Characteristics of 1 to 8 Wavelength Uniform Helical Antennas, IEEE Transactions on Antennas and Propagation, Vol AP 28, No. 2, March 1980, pp 291-296. 'Harris, E.F., Helical Antennas, Antenna Engineering Handbook, H. Jasik ed., New York McGraw-Hill, 1961, Ch 7. ' Kunde, Keith, K8KK, 'Try a 'Dopplequad' Beam Antenna for 2 Meters, OST, February 1985, pp 28-31.

AO Antenna Optimizer

Don 9t Just Analyze Designs Optimize Them Automatically The new AO 5.0 program automatically optimizes antenna designs for maximum forward gain, best pattern, minimum SWR, adequate impedance, and resonance. AO uses a conjugate-gradient technique to optimize cubical quads, phased arrays, interlaced Yagis, log periodics, V beams, or any other arrangement of wire or tubing. AO uses an enhanced, corrected MININEC algorithm for improved accuracy. For high speed, AO uses optimized, hand-coded...

Design Automation Hepaplus

Design Automation manufacturer's CAD CAE design software for RF power amplifiers should be interesting to some of you who want to design amplifiers for amateur applications. The program is called HEPA-PLUS High Efficiency Power Amplifier-PLUS . With the program, you can design linear single ended or push-pull , class AB, B, or C or switching-mode amplifiers class E or F . The program automatically optimizes the proposed design and also identifies and helps prevent design errors and omissions....

A k x bit ROM Emulator

By Dave Lichtenstein, AA6FJ and John Nemec, NS6Z 6543 Hampton Drive 2707 Estella Drive San Jose, CA 95120 Santa Clara, CA 95051 Many amateur projects can utilize microcontrollers. A major advantage of this approach is that the hardware construction can be much simpler than a discrete logic implementation. The possibilities range from simple circuits like an electronic keyer or a frequency counter and display, to more complex applications such as station control local and remote , repeater...