Active

Active Antenna HF VHF UHF  ^new - An active antenna AA-7 HF/VHF/UHF, 3-3000MHz by Fred Blechman

Active antenna for 10 to 200 Khz - Tuned active receiving antenna for 10 to 200 KHz.

Active antenna project - An active antenna amplifier schematic works from 1 to 30 Mhz

Active HF antenna - An active HF receiving antenna circuit by G7BCJ

Active magnetic Antenna - DF9CY Active Magnetic Antenna project

Active receiving antennas - An active antenna is sometimes used for receiving purposes in instances where a normal antenna would be impossible to accommodate in a physical sense.

AMRAD Active LF Antenna - The AMRAD Active LF Antenna. You can tune into LF activity with this easy-tobuild and erect active antenna. As a bonus, you get MF and HF coverage, too—not to mention world-class performance

An active antenna - Project for QRP operations by George Dobbs G3RJV

Another Approach to Active Antennas - Active antenna with a frequency response that is flat from 5kHz to over 30MHz

Simple active antenna - This circuit shows an active antenna that can be used for AM, FM, and shortwave

Why active antennas aren't perfect - There have been various comments here regarding the effectiveness of active antennas