AD8307 Module 1MHz to 500MHz wideband RF detector RF power meter ALC AGC Strength Meter FOR Ham Radio Amplifiers - AliExpress Electronic Components & Supplies
Learn on the fly : Simple AD8307 rf power meter for sweeper using ad9850 dds and arduino for testing crystals etc
Chinese AD8307 power measurement module #3 – owenduffy.net
AD8307 USB 0-500MHz RF Power Meter
Accurate USB 0-500MHz RF Power Meter Kit - Electronics-DIY.com