Tektronix 071-0590-00 user manual Generator Clock Section

Functional Overview

installed) when not in use—that is, when the Generator is driving single- ended inputs.

∙CLOCK/4 [output]: This is a clock signal at one quarter the frequency of CLOCK. This output may be useful when observing generator outputs using an oscilloscope that does not have the bandwidth to trigger on the CLOCK output.

∙PATTERN SYNC [output]: This is a pulse that occurs once per pattern frame. This output may be useful as a trigger signal when observing the Generator data output using an oscilloscope. The location of PATTERN SYNC is fixed. A pulse is generated at the start of the pattern frame.

Generator CLOCK Section

Controls in the CLOCK section of the Generator are used to select clock mode (internal or external) and to set up the instrument's internal clock. The CLOCK section also contains the input connector for an external clock source. These controls and input are introduced below.

FREQUENCY

STEP

RECALL SAVE

EXT

INPUT

(2)

50 Ohm 2 V Max

∙FREQUENCY: When this key is selected (LED on), the clock up/down keys may be used to adjust the frequency of the internal Generator clock up or down. Each press of the frequency up or down key will increment or decrement frequency by the current step size.

∙STEP: Select this key to adjust the frequency adjustment step size from 1 kHz to 100 MHz.

∙SAVE: Use this key to save the present frequency into one of 10 frequency memory locations.

∙RECALL: Use this key to recall a previously saved frequency.

∙EXT: Press this key to toggle between internal clock mode (LED off) and external clock mode (LED on).

∙INPUT : This is an input for an external clock source. A signal must be provided to this input when clock mode is set to external. However, when clock mode is internal, any signal appearing at this input will be ignored.

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