I measured FSS's open loop transfer function.
For FSS servo schematic, see D040105-B.
4395A's source out is connected to Test point 2 on the patch panel.
Test Point 2 is enabled by FSS medm screen.
"A" channel is connected to In1, on the patch panel.
"R" channel is connected to In2, on the patch panel.
the plot shows signal from A/R.
Note that the magnitude has not been corrected for the impedance match yet.
So the real UGF will be different from the plot.
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4395A setup
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network analyzer mode
frequency span 1k - 10MHz
Intermediate frequency bandwidth 100Hz
Attenuator: 0 for both channels
Source out power: -30 dBm
sweep log frequency
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medm screen setup
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TP2: enabled
Common gain -4.8 dB
Fast Gain 16 dB |