Manual for Integra TMF 1800H Prog YIG Filter???

Does anyone have a manual or know the GPIB programming syntax for the Integra Microwave TMF 1800H Programmable YIG Filter? I bought one used with no manual.

or if you know the GPIB syntax can you share it with me. I have tried hacking to find the IEEE488 GPIB syntax but no avail. It always returns 0FFFFF which I think is a DAC value but I have no way to set this value. The GPIB seems to respond so I think it is working.

Thanks i hope

Jeff Meyer
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