Recommendations for GPIB to Fiber extenders

[mmikeinsantarosa]

I need to be able to isolate my GPIB cabling into an anechoic chamber using a pair of GPIB to Fiber extenders. I have a pair of HP 37204 extenders but when I connect them up to my NI PCIe GPIB card, Automation explorer reports "Too many listeners" and won't even try to poll the port. When I connect the same extenders up to a Keysight PCIe card, it reports 240 GPIB devices found and makes the interface "Connection Expert" basically unusable. Can anybody recommend a brand/model of GPIB/Fiber extenders that behave with NI GPIB?