Fluke 96000 Series Service Manual page 98

96000 Series
Service Manual
The procedure makes use of an ac measurement standard, followed by a Power
Meter and sensors, and finally, a Spectrum Analyzer/Measuring Receiver. At
various points within the process values previously measured using one
reference device are required for subsequent use with another device. It is
recommended that users familiarize themselves with the entire absolute-level
accuracy test procedure before commencing.
Unwanted interference from signals at 10 MHz due to the frequency
reference outputs of equipment operating in the vicinity of the test
setup or the equipment used during the tests can cause erroneous
results. To avoid such problems, when test frequencies are from
10 MHz to 300 MHz, add a small offset (50 kHz) to the nominal
frequency if the test frequency is a multiple of 10 MHz.
1. Connect the UUT Microwave Output to the INPUT 1 connector on the ac
Use a common mode choke to obtain satisfactory noise performance
and accurate readings. Insert the common mode choke in series
between the feedthrough termination and the AC Measurement
Standard input, with the ground applied at the choke input. Keep the
ground connection as short as possible and set the AC
Measurement Standard to Internal Guard. A common mode choke of
250 µH is usually effective. A suitable choke is 6 turns of small-
diameter coaxial cable through a TDK toroid, manufacturer's part no.
H5C2-T28-13-16 (available as Fluke part no. 474908) Refer to the
5970A Operator Manual for additional explanation.
Measurements made on the 5790A 2.2 mV range (at levels
below -40 dBm) require correction for the 2.2 mV range linearity
error.
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measurement standard using a cable and precision 50 Ω feedthrough
termination located at the ac measurement standard input. (If a Type-N
feedthrough termination is not available, use a BNC 50 Ω feedthrough
termination and appropriate adapters. Ensure that BNC connector contact
resistance and repeatability does not significantly degrade measurement
uncertainty). Select INPUT 1. See Figure 3-15. Microwave Output Level
Accuracy Tests, Low Frequency Points Connections for equipment
connections.
Note
Note
Note