Giga-tronics Series 12000A, Руководство по эксплуатации

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Performance Verification
Publication 31231, Rev. J, October 2003 4-7
4.2.5 RF Output Power Tests
4.2.5.1 Description
Although it is possible to make the following measurements manually, it is extremely tedious. It is
recommended that an automated system be set up to take and record the data. Three tests are run. The
first measures the maximum available output with the level control loop disabled. The second verifies
the accuracy and flatness across the operating frequency range at a fixed output (0 dBm). The remaining
test checks the step attenuator accuracy at a number of frequencies. This section outlines the general
procedure followed by the automated system, a similar measurement could be done manually.
4.2.5.2 Equipment Required
UUT
²
Local Oscillator
²
Measuring Receiver & Sensor
²
Downconverter
²
Plotter
²
Computer & Programs
4.2.5.3 Procedure (Output Power)
1. Connect the power sensor to the 12000A. Disable the leveling system of the 12000A. Step the
frequency across the particular instrument operating range in 50 MHz increments. At each
point measure the power, apply the appropriate sensor correction factor, and plot the result.
2. Using the above setup, set the 12000A to 0 dBm with the leveling enabled. Again, step the
frequency across the operating range; measure, correct, and plot the power.
3. Repeat this procedure for the remaining test frequencies.
Figure 4-4: RF Output Power Test
NOTE:
When measuring the flatness and accuracy of the model 12000A,
consideration must be given to the various measurement uncertainties in the test
system. These include, but are not limited to, VSWR, Cal Factor uncertainty and
calibration.
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