Agilent Technologies E4406A manual Timebase Frequency, Test Setup, Purpose, Measurement Method

NOTE

NOTE

Making Measurements

Timebase Frequency

Timebase Frequency

Purpose

In the absence of a frequency counter, the measurement quickly determines the frequency difference between the instrument’s 10 MHz reference oscillator signal and an accurate, external 10 MHz frequency standard.

The timebase frequency check is not as accurate as a measurement of the 10 MHz Out signal (rear panel) using a frequency counter referenced to a frequency standard.

Measurement Method

The internal 10 MHz reference signal is compared with a reliable external 10 MHz signal which the user inputs into the front panel RF connector. The transmitter tester subtracts its 10 MHz reference from the input signal and displays the frequency difference.

Test Setup

An accurate external 10 MHz frequency signal, such as a house standard, is connected to an attenuator, which attenuates the signal to 0 dB. The attenuated 10 MHz signal is connected to the RF input of the transmitter tester. Pressing Mode, Service, Measure, Timebase Frequency will result in the display of data described below.

When setting up this test ensure that the reference is set to internal. To check this press System, Reference. The Freq Ref softkey allows you to toggle between Int (internal) and Ext (external). Make sure Int is underlined.

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