While operating 20m this afternoon a China station came on calling CQ around 1626 UTC. Called him back a few times but got no response. He had been calling for some while with no success, and I noticed his DT was 4.6. I sent a CHK CLOCK message but to no avail as he returned a few minutes later with the same DT value.
The question is If I am reading him OK (assuming correct decoding of his signal as location matched) then as he is @ +4.6 then correspondingly he would be -4.6 relative, so would it be unlikely my TX would be decoded? He seems to send QRZ often so seemingly hearing the signals but not decoding perhaps.