Temperature Related Information - Keysight N9912A Service Manual

Theory of Operation

Temperature Related Information

Temperature Related Information
Five temperature sensors are in the analyzer: two on the A4 RF board, two on
the A5 system board, and one in the battery pack.
— RF1—NA Temp Sensor (on the A4 RF board near the NA circuitry)
— RF2—SA Temp Sensor (on the A4 RF board near the SA circuitry)
— SB1—on the A5 system board near the headphone jack
— SB2—on the A5 system board near the battery compartment
— Battery pack—inside the battery pack
The battery pack has its own internal temperature sensor. The battery pack will
shut itself down in the case of extreme temperatures.
See Chapter 8 for instructions on viewing temperature readings.
See the FieldFox User's Guide, "FieldFox High-Temperature Protection"
section, for information about operation at high temperature.
The temperature readings for sensor RF2 are stored as part of the adjustment
data for the Frequency Response Preamp On/Off adjustments.
During normal operation, as each SA measurement is taken, the current RF2
temperature reading is compared tot he temperature stored for the Frequency
Response adjustment. A delta temperature is calculated. Each SA
measurement is adjusted to compensated for the delta temperature.
The internal temperature of the unit is critical when executing the TME based
software for tests and adjustments. See the TME help for detailed information.
Under typical bench top (indoor) conditions, the internal temperature of the
unit will be about 20 ×C above ambient once the internal temperature has
stabilized. It will typically take 60 to 90 minutes for the internal temperature to
stabilize when a "cold" unit is turned on.
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