Using WSPR to check reciprocity

WSPR ( Weak Signal Propagation Reporter ) is a mode created by K1JT ( Nobel Laureate
in Physics ) . The measurement results can be sent over the Internet to a common
server that presents the results in an Excel friendly format . The stations transmit 
and listen by turns and all results are uploaded . It may look like this . 
Signal / Noise level specified relates to a bandwidth of 2.5 kHz .