[TenTec] USB to multi-port RS-232 adapter

[lee berman via TenTec]

I want to use my laptop to control my Jupiter-Pegasus transceivers in dual receive mode using N4PY software.  To accomplish this I need to have either a USB to multi-port RS-232 adapter or multiple usb to RS-232 cables.  There are several chipsets used to accomplish the transition, but they don't all work well.  My questions are 1. Which chipset(s) work best with TenTec radios and, 2. Has anyone used a multi-port adapter successfully.
73,  ~Lee W1IDZ The greatest danger to our American freedom is a government that ignores the Constitution.                                    Thomas Jefferson