QROP Meter: Links
by Jason Hsu, AA0II
copyright 2003, 2008, 2010
Measuring SWR: Elmer 101 web page on directional coupler circuits
An op-amp circuit to compensate for diode losses: Elmer 101 web page on compensating for the diode drop loss
NoGaWaTT Kit Information: homebrew QRP SWR/wattmeter kit