Keysight Technologies N5247B, Service Manual

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Keysight N5247B Service Guide 5-51
Theory of Operation
Signal Separation Group Operation
A38–A41 50-dB Source Step Attenuators and A42–A45 Bias Tees
(Optional)
On 4-port models with Option 419 or 423, a step attenuator and a bias tee are
placed in the signal path of each test port between the A29–A32 reference
couplers and the A33–A36 test port couplers.
On 2-port models with Option 219 or 224, a step attenuator and a bias tee are
placed in the signal path of each test port between the A29–A32 reference
couplers and the A33 and A36 test port couplers.
The 50-dB step attenuators provide coarse power control for the test signals.
They are electro-mechanical step attenuators that provide 0 to 50 dB of
attenuation in 10-dB steps. They adjust the power level to the DUT without
changing the level of the incident power in the reference path. These
attenuators are controlled by the A21 CPU board.
The bias tees are to provide DC biasing for the DUT.
A38–A41 50-dB Source Step Attenuators and A71–74 Bias Tee
Combiners (Optional)
On 4-port models with Option 405, 420, and 425, a step attenuator and a bias
tee are placed in the signal path of each test port between the A29–A32
reference couplers and the A33–A36 test port couplers.
On 2-port models with Option 205 or 220, a step attenuator and a bias tee are
placed in the signal path of each test port between the A29 and A32 reference
couplers and the A33 and A36 test port couplers.
The 50-dB step attenuators provide coarse power control for the test signals.
They are electro-mechanical step attenuators that provide 0 to 50 dB of
attenuation in 10-dB steps. They adjust the power level to the DUT without
changing the level of the incident power in the reference path. These
attenuators are controlled by the A21 CPU board.
The bias tee combiners are to provide DC biasing for the DUT via the N5292A
PNA Millimeter Test Set and millimeter heads. Refer to
www.keysight.com/find/pna .
A50–A53 Mechanical Switches and A54 Combiner (Optional)
On 4-port models with Option 423, a mechanical switch is placed in the signal
path of each test port between the A5 and A10 26.5 GHz sources and the
A29–A32 reference couplers.
On 2-port models with Option 224, a mechanical switch is placed in the signal
path of each test port between the A5 and A10 26.5 GHz sources and the
A29–A32 reference couplers.