HP 8924E, Assembly

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Chapter 4, Periodic Adjustments
Introduction
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Calibration Equipment
The manual 10 MHz Oven Timebase Adjustment requires a frequency counter that
matches or exceeds the required accuracy for the tests performed by the Test Set.
The automated Voltmeter References adjustment requires a DC voltmeter with
±0.015% accuracy.
10 MHz Oven Timebase Adjustment
The timebase frequency is adjusted from the rear panel; it is not necessary to
remove any instrument covers.
1. Turn the Test Set on and let it warm up for at least 15 minutes.
2. Remove the factory-supplied jumper between the rear-panel 10MHz OVEN OUT and
REF INPUT connectors.
3. Connect the frequency counter to the 10 MHz OVEN OUT connector.
4. Use a screwdriver to turn the TIMEBASE ADJUST screw until a stable
10,000,000.0 Hz is measured by the frequency counter.
5. Replace the jumper between the 10MHz OVEN OUT and REF INPUT connectors.