Agilent Technologies 5988-7401EN manual Clock Sources, Measure Function Clock Source

Combining Parameters for Signal Generation Using the Agilent 81133A/81134A Pulse Generator

Clock Sources

The selected clock source defines the time base from which all other

timing parameters are derived. You can select between:

•Internal

The clock is derived from the internal YIG oscillator.

•External

•external 10 MHz reference (clock source); clock sources:external 10 MHz reference

Enable the external clock input (Clock In) to accept an external clock signal that forms the time base. The frequency is measured once by selecting the Measure function from the user interface or as a remote SCPI command (:MEASure:FREQuency?).

Measure Function

Clock Source

This value is then used to calculate frequency-dependent values, like the pulse width or the phase (available at the Channel page).

For more information about the Measure function, please refer to the Online Help.

•External 10 MHz Reference

•ext. direct (clock source); clock sources:ext. direct

Enables the external clock input (Clock In) to apply a 10 MHz reference clock. This clock is used as a reference for all timing parameters.

•Int. Direct/Ext. Direct

The direct modes allow changes of frequency without dropouts in the range of 1:2. They are used for applications (precise clock source) where dropouts would make a measurement impossible, for example, PLL frequency sweeps and microprocessor clock sweeps.

Agilent 81133A/81134A Pulse Generator User’s Guide, January 2005 73