Amazon.com: MLA-30+ Loop Antenna,0.5-30MHz Active Receiving Antenna,MLA-30 Plus Loop Antenna for HA SDR Short Medium Wave Radio,with 10m Feeder,Built-in Low Noise Amplifier,for Rooftop,Balcony : Electronics
Active antennas constructed by other hams using AAA-1
Simple active receive loop - PA1M - Amateur Radio
Top Band Receive Loop Antenna - Resource Detail - The DXZone.com