Contents Chapter 1 Quick Start The Rear Panel at a Glance 3 The Front-Panel Menu at a Glance 4 To phase lock to an external clock signal 5 To phase lock multiple function generators 7 To set a zero phase reference 9 To phase lock using the triggered burst mode 10 To generate a phase unlock error 14 Chapter 2 Remote Interface Operation...
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• Phase offset control from the front panel or over the remote interface. • Simultaneous hardware triggering of multiple HP 33120As. Option 001 allows the HP 33120A to generate a trigger pulse from the Ext Trig terminal which can be routed to other instruments in a system.
The Rear Panel at a Glance The Phase-Lock assembly adds the Ref Out and Ext Ref In terminals to allow synchronization between multiple HP 33120As or to an external 10 MHz clock signal. 1 Internal 10 MHz reference output terminal...
Chapter 1 Quick Start The Front-Panel Menu at a Glance The Front-Panel Menu at a Glance The Phase-Lock assembly adds the Phase Menu to the front-panel menu. T he menu is organized in a top-down tree structure with three levels. G: PHASE MENU ...
Chapter 1 Quick Start To phase lock to an external clock signal To phase lock to an external clock signal The rear-panel Ext Ref In terminal allows you to synchronize one or more function generators with an external 10 MHz signal. The following steps show you how to configure a single instrument for synchronization with an external signal.
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Chapter 1 Quick Start To phase lock to an external clock signal Shift 2 Turn on the menu. Menu On/Off A: MOD MENU < 3 Move across to the choice on this level. PHASE MENU G:PHASE MENU ∨ 4 Move down a level to the command.
Chapter 1 Quick Start To phase lock multiple function generators To phase lock multiple function generators The rear-panel Ref Out and Ext Ref In terminals allow you to synchronize multiple function generators. The diagram below shows how to make connections for the “real-time” phase-lock mode. In the real-time mode, the phase offset relationship is random at first.
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Chapter 1 Quick Start To phase lock multiple function generators Shift 2 Turn on the menu. Menu On/Off A: MOD MENU < 3 Move across to the choice on this level. PHASE MENU G:PHASE MENU ∨ 4 Move down a level to the command.
Chapter 1 Quick Start To set a zero phase reference To set a zero phase reference After selecting the desired phase relationship as described on the previous pages, you can set a zero-phase point. The function generator then assumes that its present phase is zero and you can adjust the phase relative to this new “zero”.
Chapter 1 Quick Start To phase lock using the triggered burst mode To phase lock using the triggered burst mode The rear-panel Ref Out and Ext Ref In terminals allow you to synchronize multiple function generators. The diagram below shows how to make connections for the “triggered burst”...
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Chapter 1 Quick Start To phase lock using the triggered burst mode Shift Burst 2 Enable the burst mode on both instruments. Notice that the annunciator turns on. Burst Shift 3 Use the menu to set the burst count on both instruments. <...
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Chapter 1 Quick Start To phase lock using the triggered burst mode Shift 6 Go to the command in the BURST PHAS MOD MENU Menu On/Off 6:BURST PHAS ∨ 7 Move down a level and set the burst phase. You can set the starting phase of the burst to any value between -360 degrees and +360 degrees.
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Chapter 1 Quick Start To phase lock using the triggered burst mode Enter 11 Save the change and turn off the menu. The external trigger setting is stored in volatile memory; the external trigger state is disabled when power has been off or after a remote- interface reset.
Chapter 1 Quick Start To generate a phase unlock error To generate a phase unlock error You can configure the function generator to generate an error condition whenever phase lock is lost. The following steps show you how to enable an unlock error.
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This chapter gives an overview of the Phase-Lock commands available to program the function generator over the remote interface. Refer to chapter 4 in the HP 33120A User’s Guide for complete details on configuring the function generator for remote interface operation.
“An Introduction to the SCPI SCPI Language,” starting on page 211 in the HP 33120A User’s Guide. Throughout this manual, the following conventions are used for command syntax. SCPI • Square brackets ( [ ] ) indicate optional keywords or parameters.
This section describes the (Standard Commands for Programmable SCPI Instruments) commands available to program the Phase-Lock assembly. Refer to chapter 4 in the HP 33120A User’s Guide for details on the complete set of commands for the function generator. radians PHASe:ADJust {<...
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Chapter 2 Remote Interface Operation Phase-Lock Commands PHASe:UNLock:ERRor:STATe {OFF|ON} Disable or enable the function generator from generating an error if phase-lock is ever lost. If phase-lock is lost and the error is enabled, 580, “Phase-locked loop is unlocked” is generated. The default is OFF . [ Stored in non-volatile memory ] PHASe:UNLock:ERRor:STATe? Query the unlock error state.
Refer to chapter 6, “Application Programs,” in the HP 33120A User’s Guide for more details and examples. Also refer to the programming reference manual that came with your computer for details on outputting command strings and entering data.
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Chapter 2 Remote Interface Operation Simplified Programming Overview To Phase Lock Multiple Function Generators The rear-panel Ref Out and Ext Ref In terminals allow you to synchronize multiple function generators. The following statements show you how to synchronize two function generators at 10 kHz (send the commands to both function generators): Select sine function at 10 kHz "APPL:SIN 10E+3, 5.0"...
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Chapter 2 Remote Interface Operation Simplified Programming Overview To Phase Lock Using the Triggered Burst Mode In the triggered burst mode, you can synchronize phase-lock signals using an external trigger from the rear-panel Ext Trig terminal. The following statements show you how to synchronize two function generators in the triggered burst mode (send the commands to both function generators): Set both to the same frequency...
SCPI An example program is included in chapter 6, “Application Programs,” of the HP 33120A User’s Guide which shows the use of the status registers. You may find it useful to refer to the program after reading the following section in this chapter.
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Chapter 2 Remote Interface Operation The SCPI Status Registers SCPI Status System...
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Chapter 2 Remote Interface Operation The SCPI Status Registers The Questionable Data Register The Questionable Data register reports the present lock state on bit 6. The state of this bit can be reported in the Questionable Data summary bit through the enable register. To set the enable register mask, you must write a decimal value to the register using the STATus:QUEStionable:ENABle command.
Chapter 2 Remote Interface Operation Status Reporting Commands Status Reporting Commands STATus:QUEStionable:CONDition? Query the Questionable Data condition register and return the real-time value of all bits set. Returns “0” if phase is locked or “64” if phase is unlocked. enable value STATus:QUEStionable:ENABle <...
Phase-Lock Error Messages Phase-Lock Error Messages This section lists the two error messages that can be generated if the Phase-Lock option is installed. Refer to chapter 5 in the HP 33120A User’s Guide for a complete listing of error messages. -221 Settings conflict;...
The parts lists include a brief description of the part with applicable HP part number and manufacturer part number. See the HP 33120A Service Guide for complete details on the servicing and warranty policies of the HP 33120A. To Order Replaceable Parts...
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Chapter 4 Replaceable Parts and Schematics 33120-66503 – Phase-Lock PC Assembly 33120-66503 – Phase-Lock PC Assembly Reference HP Part Mfr. Mfr. Part Designator Number Part Description Code Number C101 0160-5945 CAP-FXD 0.01 uF 50 V 04222 08055C103KAT A C102 0160-5955...
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Chapter 4 Replaceable Parts and Schematics 33120-66503 – Phase-Lock PC Assembly Reference HP Part Mfr. Mfr. Part Designator Number Part Description Code Number R113 0699-1392 RESISTOR 11K +-1% .125W TKF TC=0+-100 19701 9C12063AFKR R114 0699-1372 RESISTOR 1.47K +-1% .125W TKF TC=0+-100...
25403 NV Philips Elcoma Eindhoven, Netherlands 02876 27014 National Semiconductor Corp Santa Clara, CA, U.S.A. 95052 28480 HP Div 01 San Jose Components San Jose, CA, U.S.A. 95131 80031 Mepco Electra Corp Morristown, NJ, U.S.A. 07960 91637 Vishay Electronic Components Columbus, NE, U.S.A.
Index If you have questions relating to the operation of the function generator, 1-800-452-4844 in the United States, or contact your nearest call Hewlett-Packard Sales Office. *OPT? command, 19 Phase Menu, 4 phase offset, 6, 8, 20 fanout (triggering), 30 accuracy, 30 frequency stability, 30 range, 30...
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Index safety information, inside front cover technical specifications, 30 schematic diagram, 37 timebase accuracy, 30 SCPI language triggered burst mode (phase lock), 10, 22 command format, 17 triggering command summary, 17 fanout, 30 programming overview, 20 - 22 from Ext Trig terminal, 13, 22 status registers, 23 - 25 pulse width, 30 syntax conventions, 17...
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Windows NT are regis- be returned to a service and exclusive remedies. tered trademarks of Printing History facility designated by HP. HP shall not be liable for Microsoft Corp. Edition 1, August 1994 any direct, indirect, special, For products returned to Safety...