Boonton 4530 Series, Руководство по обслуживанию и калибровке

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BOONTON ELECTRONICS a WIRELESS TELECOM GROUP COMPANY
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Construct the calibration setup as shown below. The use of a second 4530 (“reference powermeter”) to
make the calibration measurements is the preferred method, but is not strictly necessary. Since all
readings are relative to the
test calibrator’s output, there is no requirement that the reference powermeter
have high absolute measurement accuracy.
When reference powermeter is operated in relative mode, sensor and powermeter calibration
uncertainties cancel out, and the only significant uncertainty with this method is the difference between the
two paths through the switch. Every effort should be taken to ensure that the two paths from the switch to
the calibrator outputs are the electrically identical. This differences between the two paths can be easily
measured (S21) and can usually be kept very small (>0.01dB) at 50MHz.
Boonton 4530 UUT Boonton 2520 Upside down
DC PS
HP8761A
2 M toM Type N
4 M to F Type N 90
Boonton 51075
CW Sensor
Coaxial Switch
Control Ckt.
Boonton 4530
(Optional)
Test Setup
The switch should be wired so the output of the reference calibrator (Boonton Model 2520) is routed
through an adapter to input “A” of the HP8761A Coaxial Switch, and the output of the UUT’s calibrator is
routed through an identical adapter to input “B” of the switch. The reference powermeter’s sensor is
connected to the switch common.
It is possible to connect the HP8761A Switch and a sensor to the same UUT at the same time by
orientating the adapters and instruments such that the sensor port is not obstructed. RF cables
(electrically identical and short in length) can be used in place of the adapters.
Covers should be installed on all instruments, and the temperature of the test area should be stable to
within one degree Celsius for the duration of the procedure.
Test Terminology
Since the reference 4530 is optional, The term
UUT will be used here to refer to the 4530 containing the
calibrator being calibrated, and Meas4530 will refer to the reference powermeter making the
measurement. If the same instrument that contains the calibrator being calibrated is also used to
measure the power ratios, all commands are
sent to that instrument.
[Select UUT] means set the coaxial switch to the test calibrator’s output, and [Select 2520] means set the
coaxial switch to the output of the reference 2520 calibrator
Scans by ArtekMedia => 2009