This adjustment should only be performed if the 2nd LO power measured at A20J6 is not between -6 dBm and -7 dBm when the PSA is tuned to 2 GHz and placed in Zero Span.
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This adjustment should only be performed if the 2nd LO power measured at A20J6 is not between -6 dBm and -7 dBm when the PSA is tuned to 2 GHz and placed in Zero Span. |
To perform this adjustment the instrument cover and top shield must be removed to access the LO Test Port, but it is not necessary to put PC assemblies on extenders.
This adjustment measures the 3.6 GHz 2nd LO Power at the A20 Lowband 2nd LO Test Port, A20J6, with a power meter. The power is controlled by a DAC on the A13 Front End Driver. The 2nd LO power is adjusted for a target power of -6.8 dBm. When the target power is achieved the 2nd LO Power Detector ADC voltage is read. The 2nd LO ADC reading is then stored on the Front End Driver board. When a PSA internal alignment is performed, the 2nd LO power is internally adjusted until the 2nd LO ADC reading matches the value stored on the Front End Driver board, thus insuring the Second Mixer is being driven with the correct LO power.
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This adjustment saves an output file which lists the corrections that were stored in the instrument. The output file is saved at this location:
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Test Equipment |
Model Number |
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Power Meter |
N1914B |
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Power Sensor |
N8481A |
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Type-N (f) to 3.5 mm (m) adapter |
1250-1750 |
