| Synopsis |
Transmitting and Receiving Antennas Have Different Jobs to Do.
Although the fundamental characteristics of antennas apply to both transmission and reception, the requirements and priorities of receiving antennas can be vastly different from those of transmitting antennas. Receiving Antennas for the Radio Amateur focuses entirely on active and passive receiving antennas and their associated circuits. There are relatively few cases where a radio amateur cannot benefi t from a separate, well-designed receiving antenna or antenna system. On the low bands, including our new allocations at 630 and 2200 meters, heavy emphasis on the receiving end of these radio paths is essential for success.
The active antenna holds a prominent position in this book, as it offers good receiving performance while taking up minimal space. Recent developments in radio frequency (RF) semiconductors, especially low-noise RF operational amplifiers, have made a number of previously difficult-to-implement active antenna designs simple to build.
Table of Contents:
Receiving Antennas are Different!
Your Friend, the Decibel
The Preamplifi er Problem
The Amazing Disappearing Antenna
The Receiving Antenna as a
Signal Generator
The Quest for Infi nite Power Gain
The Role of the Resistor in the
Receiving Antenna
The Small Loop Antenna
Achieving the Perfect Null
You Can Make Accurate
Field Strength Measurements
The Aperiodic Loop
The Q Factor
The Beverage: In a Class of Its Own
Dealing with Non-Reciprocal Propagation
The Evolution of the eXOgon Antenna
The Lowdown on LF
The Random Wire
Arrays and Beamforming Networks
Powering Your Active Antenna
Diversity Methods
NVIS Receiving Antennas
Receiving Antenna Projects and Accessories
Materials and Construction Techniques
Our Two New Bands |