We have an old product coming back into production. Testing of this product was done using a program written in VB5 on an external PC with a National Instruments GPIB card connected to an 8510. Is it possible to run VB5 code on the internal PNA's PC? Do I use a USB to GPIB convertor to operate the PNA, using the USB and GPIB port in the back of the PNA? The problem I see is I don't believe VB5 had very good support for USB. I realize I may have to rewrite some of the code but I'm hoping to avoid a complete rewrite.