HP E42 manual Function of CONTROLS, INDICATORS, INPUTS, and Outputs

Model 5328A

Operation

3-25. FUNCTION OF CONTROLS, INDICATORS, INPUTS, AND OUTPUTS

3-26.The following paragraphs provide a detailed description of the function of controls, indi- cators, and connectors.

3-27.Display

3-28.The 5328A counter display consists of nine-digit, seven-segment LED display and annun- ciators for indicating the measurement units of Hz, s, as well as multiplier indicators (K, m, ~, n). These display units and multipliers are automatically displayed along with the correct deci- mal point location. Overflow (OVFL) indicates that left-most-significant digits have overflowed the display. Remote (RMT) indicates that the counter (HP-IB interface) is under remote program control. A GATE lamp indicates that the counter has been armed and that a measurement is in process.

3-29.Power (Line)

3-30.The LINE switch puts the counter in OPER (operate) or STBY (standby). The STBY position with STBY light on turns off some but not all the power supply voltages. This circuit arrangement allows the high stability oscillator to operate continuously. Therfore, the input to main power transformer (T1) plus the unregulated dc voltage to the oscillator oven is always energized whenever power is connected even with the line switch in STBY.

3-31.Reset

3–32.The RESET pushbutton resets the display and internal count to zero and also initiates single measurements when the SAMPLE RATE control is in the HOLD mode, The HP-IB interface, provides remote control capability, pushing the RESET button restores the counter to local con- trol (when not remotely locked out by the HP-IB Local Lockout universal command). Refer to programming in this section.

3-33.Sample Rate Control

3–34.The SAMPLE RATE control sets the minimum time between samples, The time is con- tinuously variable from less than 2 milliseconds between measurements to HOLD, which holds the display indefinitely.

NOTE

The counter will internally (self) arm (via the SAMPLE RATE control) only when ARMing is OFF and the FUNCTION selected is at other than FREQ A, FREQ C, and RATlO C/A.

3-35.Arming

3-36.The counter may be armed internally (i.e., made ready to start a measurement) by the SAMPLE RATE control, or externally by the input signal itself, (arming off) or by a signal not directly involved in the measurement (arming on). Table 3-7is an arming status table. A rear panel switch turns ARMing either ON or OFF. The counter is armed within 1 ps after the event at the B arming input and is armed within 10 ps after the event of the C arming input.

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