USB to Serial
With Radio communications or Fiber communications, the computer will need to have a COMPORT, however most computers today do not have them. The Keyspan USA-19HS works well. This type of adapter you will also need a serial cable between the Keyspan (comport) and the sign controller (or HN232 device).
The TRIPP-LITE U209-000-R. This cable have USB on one end and comport on the other end, so you would not need any other cable or adapter between the computer and the comport of the sign controller (or HN232 device). HOWEVER this unit seems to connect to the V4 Sign Controller at a slower speed.
Another brand we would recommend using is the Radio Shack model 2603487 (includes Windows 8 support) or their older model 26-949 (up to Windows 7 support). These cables have USB on one end and comport on the other end, so you would not need any other cable or adapter between the computer and the comport of the sign controller (or HN232 device).
These cables do come with an install disc that will have the Windows drivers on it.
NOTE: when using a USB to Serial adapter the USB should be plugged directly into the computer, do not plug it into a USB hub. When plugging in the USB to Serial converter and a laptop (or any computer), make sure you always plug it into the same USB port on the computer. The computer will change the comport number when using different USB ports.
Driver for Gigaware 26-949
Driver for Gigaware 26-3487