Cannot open PNA E8364C with VNA Tools 2.5

[mauro foti]

Hello,

we are upgrading our software and we have an issue with VNA Tools and our Agilent PNA E8364C, specifically, when testing or opening the device, VNA Tools throws a VisaTimeout exception, and the Pna returns an error "QUERY UNTERMINATED", making it unusable. If we send an identification string with an external program (like NI-MAX), the Pna responds correctly

The weird thing is that, this new computer (Windows 10, VNA Tools version 2.5.8091.31424, a USB-GPIB interface) works with all our other VNAs (an HP8510C and an Agilent ENA E5061B), it only refuses to communicate with the Pna.

We know that the analyzer works because with the older workstations (Windows XP/7, VNA Tools version 1.6.5777.20096, another USB-GPIB interface and a PCI card) we can use it without any issue.

We already tried copying the compiled drivers from the older machines, but of course they don't work (they just don't show up on the drivers list), which is understandable. What could be done to fix this issue? Is it a bug in a newer driver? Looking at the driver source code the commands appear to be pretty much the same from one version to the other.

[Michael Wollensack METAS]

Hi,

this is bug introduced in V2.5.2 of VNA Tools. There is workaround for it, see

see https://groups.google.com/g/vnatools/c/a2VOH36mMt8/m/DUNy-GvYAAAJ

It will be fixed in V2.5.4 which will be released this or next week.

Regards

Michael