Thanks for looking.
I think I know what's happening. Satpc32 Commands the TS2000 Receiver A and B (SSB U/L) about every few sec for doppler correction and frequency read. ACL polls the TS2000 every 2 sec by setting. This occurs over a single COM port using a virtual COM port splitter.
Please refer to the screenshots attached. Does the ACL code ignore the tag FA or FB of received data to determine which Receiver frequency to enter into the log? Or does it ignore the Tag assuming it is the response from the Receiver that was commanded to read? When Satpc32 is not running, ACL works fine. Please confirm.