A38-A41 60-Db Source Step Attenuators And A42-A45 Bias Tees (Optional); A50-A53 Mechanical Switches And A54 Combiner (Optional) - Keysight N5244A Service Manual

Theory of Operation
Signal Separation Group Operation
A38–A41 60-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 and A32 reference
couplers and the A33 and A36 test port couplers.
The 60-dB step attenuators provide coarse power control for the test signals.
They are electro-mechanical step attenuators that provide 0 to 60 dB of
attenuation in 5-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.
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
and A32 reference couplers.
These switches allow the source signal to be routed to or from rear-panel
connectors. The internal source signal can be sent out through a rear-panel
connector to be made available for external use or an external source signal
can be input through a rear-panel connector to be used in place of the internal
source signal.
In the port 1 signal path, there is an additional reference coupler (A54) which,
when switched into the signal path, is used as a combiner to combine two
source signals from the rear panel. These signals typically come from the
analyzer's two internal sources and are jumpered on the rear panel.
5-24 Keysight N5244A/45A Service Guide