[amsat-bb] LVB tracker issue

I had the USB port on my LVB go out after a voltage surge that took out my computer. I removed the USB board and put the chip in for serial control. With the DB9 connected to computer with real serial port(not USB/serial converter) the LVB will not always track right. I use for EME and SAT and sometimes it will just idle when it shold be tracking. Are there any port settings that I need to change or any advice when used via serial cable. Also is the USB board available just as single part.

Thanks for any info, 73, Joe KI4TZ