Connectors

Connectors

EXT REF IN

This connector allows you to input an external reference. The reference frequency is selected using the Ext Ref In field on the INSTRUMENT CONFIGURE screen.

Operating Considerations

Input frequency = 1, 2, 5, 10, or 15 MHz; 1x, 2x, 4x, 8x, or 16x chip

Input level >0.15 V rms

Input impedance approximately 50Ω .

When a valid signal is applied to the EXT REF IN port, the Test Set automatically switches from internal to external reference if the Ref Select field is set to Auto.

This signal is used as a reference for, and directly affects, these functions:

RF Generator Frequency (including the Tracking Generator)

RF Frequency Counter

AF Frequency Counter

RF Analyzer Tune Frequency

Spectrum Analyzer Center Frequency

CDMA Generator Frequency

CDMA Analyzer Frequency

 

AF generators 1 and 2 are not affected using an external reference; they use their own

 

reference.

 

 

NOTE

The reference output frequency is always 10 MHz, independent of the selected input

 

reference frequency.

 

Electrostatic discharges to the EXT REF IN port of 0.5 kV or above may cause

 

degradation of performance requiring operator intervention.

Chapter 9

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Agilent Technologies 8935 series e6380a manual Ext Ref