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Trouble with upgrading 8720es control code fromVEE6/Win2000 to VEE9.3/Win7

Question asked by SteveE. on Mar 23, 2016
Latest reply on Mar 24, 2016 by Mike
Over a decade ago I wrote some code (VEE6/Win2000) to do a power flatness calibration on an 8720es having the computer set up the 8720 parameters and then do a power cal by stepping thru the 201 points using external manual trigger to single step. The computer then would read the 4418A/B power meter and build up a flatness correction table that I would then download to the 8720 via the INPUPMCAL command. The routines worked well and allowed me to create dozens of power cals with different frequency ranges and power levels, saving them as files on the computer and downloading them as needed for various measurements. This all worked until (due to security requirements) we had to upgrade to WIn7 and VEE 9.3. SInce then the power cal routine still works to create the flatness table, but nothing I have tried will successfully transfer the table down into the 8720. When I read back the power correction memory all I get is a 201 point array of the value -4600 (the 8720 power setting is -46dBm in this example). The data I send out to the 8720 is 201 points of the corrected power level in the same format of (setting *100) i.e. -4309,-4258,-4204...) the original code sent the array in string format, but I have tried text Real 64 with and without limits on the significant digits, and string format with and without limits on number of characters.. I monitor the GPIB bus traffic with an old school VEE 7.5 bus monitor object and everything looks like it should but nothing seems to work. I have thought about setting up the 8720 to control the power meter and allowing it to run the power cal and then downloading the power correction array, but without being able to download the power cal back into the 8720 that would be of no value. Can anyone suggest anything to try? If anyone is willing to contact me directly for more information or to provide any help I can be reached at or 408 624-3173 (8AM-5PM PST) 

Thank You all for taking the time to read this and for any help you might be able to provide

Stephen Estrin 
Principle Test Engineer at Cobham MES