HP E4418A, Service Manual

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Adjustments
Power Reference Oscillator Level Adjustment
3-6 HP EPM-441A/442A Service Guide
Power Reference Oscillator Level Adjustment
Description
The power reference oscillator is factory adjusted to 1.0 mW
±
0.7%. This is
done using a special measurement system accurate to 0.5% traceable to
the National Institute of Standards and Technology (NIST) and allowing
for a 0.2% transfer error. To ensure maximum accuracy in re-adjusting the
power reference oscillator, the following procedure provides step-by-step
instructions for using specified Hewlett-Packard instruments of known
capability. If equivalent instruments are used, signal acquisition criteria
may vary and reference should be made to the manufacturer’s guidelines
for operating the equipment.
Note The power meter may be returned to the nearest HP office to have
the power reference oscillator checked and/or adjusted.
Figure 3-3: Adjustment Setup
Power Meter
HP 432A
Power Meter
V
RF
V
comp
HP 478A
Option H75
Digital
Multimeter
POWER
REF
INPUT
INPUT
+
4402serv.book Page 6 Monday, March 11, 2002 11:34 AM