Today, I was monitoring changes to transmit Doppler shift of CAS-4B using SatPC32 software. As expected, as CAS-4B approached my QTH, the frequency increases. However, as the satellite passed nearly overhead, I was expecting to see a downward frequency shift reversal but that didn't happen until CAS-4B's footprint was far away, well past the Caribbean. Can someone explain why there's not a frequency reversal at the time the satellite is overhead?
Paul, W9AC