Power Coupling Options - Agilent Technologies 8753ET User Manual

NOTE After measurement calibration, you can change the power within a range and still maintain
nearly full accuracy. In some cases better accuracy can be achieved by changing the power
within a range. It can be useful to set different power levels for calibration and measurement
to minimize the effects of sampler compression or noise floor.
If you decide to switch power ranges, the calibration accuracy is degraded and accuracy is
no longer specified. However, the analyzer leaves the correction on.
The annotation C will be displayed whenever you change the power after calibration.

Power Coupling Options

There are two methods you can use to couple and uncouple power levels with the analyzer:
• channel coupling
• port coupling
By uncoupling the channel powers, you effectively have two separate sources. Uncoupling the test ports
allows you to have different power levels on each port.
Channel coupling
CH PWR [COUPLED]
power coupled, the power levels are the same on each channel. With the channel power uncoupled, you can
set different power levels for each channel. For the channel power to be uncoupled, the other channel
stimulus functions must also be uncoupled (
Test port coupling
PORT PWR [COUPLED]
coupled, the power level is the same at each port. With the ports uncoupled, you can set a different power
level at each port. This can be useful, for example, if you want to simultaneously perform a gain and reverse
isolation measurement on a high-gain amplifier using the dual channel mode to display the results. In this
case, you would want the power in the forward direction (S
direction (S ).
12
toggles between coupled and uncoupled channel power. With the channel
COUPLED CH OFF
toggles between coupled and uncoupled test ports. With the test ports
).
) much lower than the power in the reverse
21
Operating Concepts
Output Power
7- 11