[amsat-bb] SO50 Help Please

My equipment is an FT-847 feeding a pair of 8 element RHCP antennas with Advanced Research Preamps mounted at the antenna.  I use SatPC for the automatic tracking.  I am supposedly transmitting a 67 Hz PL on TX.

Ar elevations above 40 degrees, I can hear AO50 full quieting with just a little fading.  What I can not sdeem to do is TX through AO50.  I can TX OK through AO51 in its current mode (QRP transponder and no PL) but not AO50.  I seemed that if TX right when someone ended the TX, I could get in for a fraction of a second.  Can anybody tell me what I am doing wrong?  Is their some quirk with PL in the Sat Mode on the FT-847?

Any help would be appreciated.  Thanks.