SRS Labs SR850 5-55, Setup Plotter

5-55

System Setup Menu

Define

Pens:

Return:

RS232 GPIB

Slow

Plot Speed

Baud Rate

Plot Mode

9600 bd

Fast

Setup Plotter The Setup Plotter submenu configures the SR850 plotter driver. Inter-

face, plot speed, and pen definitions are set in this submenu. To actually

start plotting, use the [PLOT] key to select the Plot menu.

Plot Mode The SR850 can drive either an RS232 or GPIB interface plotter. The plot-

ter must be HP-GL compatible. This function selects which interface to

use. The plotter connects to the RS232 or GPIB connector on the rear

panel.

Baud Rate If the Plot Mode is RS232, then the Baud Rate for the

plotter may be selected. The baud rate is adjusted using

the knob and must match the baud rate of the plotter.

Plotter Address

Return

Cursor Pen

Alpha Pen

Grid Pen

Trace Pen

Define Pens

Plot Speed

Baud Rate

Settings

Plot Mode

Plotter

RS232 GPIB

SYSTEM

SETUP

Baud Rate

9600 bd

Contents

Main MODEL SR850 DSP Lock-In Amplifier Stanford Research Systems Page TABLE OF CONTENTS 1-1 GENERAL INFORMATION GETTING STARTED Table of Contents 1-2 TESTING SERVICE CIRCUITRY SAFETY AND PREPARATION FOR USE WARNING 1-3 Page SR850 DSP LOCK-IN AMPLIFIER 1-5 SPECIFICATIONS SR850 DSP Lock-In Amplifier 1-6 1-7 COMMAND LIST 1-8 1-9 1-10 STATUS BYTE DEFINITIONS GETTING STARTED YOUR FIRST MEASUREMENTS Key Types Hardkeys Softkeys Page 2-3 THE BASIC LOCK-IN 2-4 2-5 2-6 2-7 DISPLAYS and TRACES 2-8 2-9 2-10 Page Page 2-13 OUTPUTS, OFFSETS and EXPANDS 2-14 2-15 2-16 2-17 SCANS and SWEEPS 2-18 2-19 2-20 2-21 2-22 2-23 USING THE DISK DRIVE STORING AND RECALLING DATA 2-24 2-25 2-26 2-27 2-28 2-29 STORING AND RECALLING SETTINGS 2-30 2-31 AUX OUTPUTS and INPUTS 2-32 2-33 Page 2-35 TRACE MATH 2-36 2-37 2-38 2-39 2-40 2-41 Page SR850 BASICS Why use a lock-in? What is phase-sensitive detection? WHAT IS A LOCK-IN AMPLIFIER? 3-1 3-2 Narrow band detection Where does the lock-in reference come from? All lock-in measurements require a reference signal. Magnitude and phase WHAT DOES A LOCK-IN MEASURE? RMS or Peak? Degrees or Radians? Page 3-5 THE FUNCTIONAL SR850 SR850 FUNCTIONAL BLOCK DIAGRAM Page 3-7 Reference Input Internal Oscillator REFERENCE CHANNEL Reference Oscillators and Phase Phase Jitter 3-8 Harmonic Detection THE PHASE SENSITIVE DETECTORS (PSD's) 3-9 Digital PSD vs Analog PSD Page 3-11 Time Constants Digital Filters vs Analog Filters TIME CONSTANTS and DC GAIN Synchronous Filters 3-12 Long Time Constants DC Output Gain What about resolution? DC OUTPUTS and SCALING 3-13 X and Y CH1 and CH2 X, Y, R and Output scales 3-14 Trace displays Trace output scaling 3-15 Page 3-17 What is dynamic reserve really? DYNAMIC RESERVE 3-18 Dynamic reserve in the SR850 Minimum dynamic reserve 3-19 Input noise SIGNAL INPUT AMPLIFIER and FILTERS Notch filters 3-20 Anti-aliasing filter Input Impedance 3-21 Single-Ended Voltage Connection (A) INPUT CONNECTIONS 3-22 Current Input (I) AC vs DC Coupling 3-23 Johnson noise INTRINSIC (RANDOM) NOISE SOURCES ( ) Page 3-25 Capacitive coupling Inductive coupling EXTERNAL NOISE SOURCES 3-26 Resistive coupling or ground loops Microphonics Thermocouple effects 3-27 NOISE MEASUREMENTS 3-28 R noise POWER BUTTON FRONT PANEL 4-1 4-2 Front Panel SOFT KEYS KEYPAD SPIN KNOB 4-3 Front Panel Page 4-5 X = 9.7284 mV Y =-1.2050 mV SCREEN DISPLAY 4-6 DATA TRACES 4-7 X = 9.7284 mV SINGLE and DUAL TRACE DISPLAYS Page 4-9 X = 9.7284 mV BAR GRAPHS 4-10 POLAR GRAPHS 4-11 STRIP CHARTS 4-12 4-13 TRACE SCANS, SWEEPS & ALIASING 4-14 4-15 SETTINGS & INPUT/OUTPUT MONITOR MENU DISPLAY 4-16 STATUS INDICATORS 4-17 Page KEYPAD 4-19 8 AUTO SRS 4-20 ADDITIONAL MENUS ENTRY KEYS [START/CONT] and [PAUSE/RESET] 4-21 [CURSOR] [ACTIVE DISPLAY] [MARK] 4-22 [CURSOR MAX/MIN] [AUTO RESERVE] [AUTO GAIN] [AUTO PHASE] 4-23 [PRINT] TO A PRINTER [PRINT] TO A DISK FILE [HELP] [LOCAL] Page 4-25 POWER ENTRY MODULE REAR PANEL 4-26 Rear Panel REAR PANEL BNC CONNECTORS AUX IN 1-4 (A/D Inputs) AUX OUT 1-4 (D/A Outputs) 4-27 Rear Panel TRIG IN TTL OUT PREAMP CONNECTOR Page SR850 MENUS 5-1 5-2 SR850 Menus DEFAULT SETTINGS REFERENCE AND PHASE MENU Reference and Phase 5-3 Reference Phase Auto Phase 5-4 Reference Source 5-5 5-6 Harmonic Sine Output INPUT AND FILTERS MENU Input and Filters 5-7 Source Current Gain 5-8 Input and Filters Menu Grounding Coupling Line Notches GAIN AND TIME CONSTANT MENU Gain and Time Cons 5-9 Sensitivity 5-10 Reserve 5-11 Man Reserve Auto Reserve Time Constant 5-12 Analog Outputs with Short Time Constants 5-13 Filter dB/oct Synchronous Note Page OUTPUT AND OFFSET MENU Output and Offset 5-15 Front Panel CH1 and CH2 5-16 Output and Offset Menu Output Offset and Expand TRACE AND SCAN MENU Trace and Scan 5-17 Trace 5-18 Trace and Scan Menu Sample Rate 5-19 Trace and Scan Menu Scan Length Page DISPLAY AND SCALE MENU Display and Scale 5-21 Format Monitor 5-22 Display and Scale Menu Page Page AUX OUTPUTS MENU Aux Outputs 5-25 Aux Outputs 5-26 Aux Outputs Menu Voltage Sweep Limits 5-27 Aux Outputs Menu Trigger Starts? Page Cursor Seek Cursor Setup CURSOR SETUP MENU 5-29 5-30 Cursor Setup Menu Cursor Width Vert Grid Divs Cursor Control EDIT MARK MENU 5-31 5-32 Edit Mark Menu Edit Mark Delete Mark Cursor to Next MATH MENU Math 5-33 Math Keys 5-34 Smooth 25 point 21 point 17 point 11 point 5 point 5-35 Fit Do Fit Type of Fit View Parameters 5-36 5-37 Left and Right Limit Return 5-38 Calc Do Calc Operation 5-39 Argument Type 5-40 Stats Do Stats Left and Right Limit Disk Keys DISK MENU Disk 5-41 5-42 Save Data 5-43 5-44 Recall Data 5-45 5-46 Save Settings 5-47 Recall Settings 5-48 Disk Utilities SYSTEM SETUP MENU 5-49 System Setup Setup Keys 5-50 Settings Keys Settings 5-51 Setup Communications Output to RS232/GPIB 5-52 Setup GPIB Setup RS232 5-53 View Queues 5-54 Setup Sound Key Click Alarms 5-55 Setup Plotter Plot Mode 5-56 Plot Speed Define Pens 5-57 Setup Printer Printer Type 5-58 Setup Screen Move Right Move Left Move Up Move Down 5-59 Setup Time Time Date Page 5-61 Plot All 5-61 Plot Trace Plot Cursor Plot Abort Return Plot Page 5-63 About the SR850 About SRS Operating Hints Command List Status Bytes Return Info Page 5-65 Keypad Test Keyboard Test Knob Test Test Hardware 5-66 Disk Drive Test RS-232 Test Memory Test Screen Test Printer Test REMOTE PROGRAMMING 6-1 6-2 INTERFACE READY AND STATUS GET (GROUP EXECUTE TRIGGER) 6-3 DETAILED COMMAND LIST correct interface at the beginning of every program. Remember! 6-4 REFERENCE and PHASE COMMANDS Page 6-6 INPUT and FILTER COMMANDS 6-7 GAIN and TIME CONSTANT COMMANDS Page 6-9 OUTPUT and OFFSET COMMANDS 6-10 TRACE and SCAN COMMANDS 6-11 DISPLAY and SCALE COMMANDS 6-12 6-13 CURSOR COMMANDS 6-14 MARK COMMANDS 6-15 AUX INPUT and OUTPUT COMMANDS 6-16 MATH COMMANDS 6-17 6-18 STORE AND RECALL FILE COMMANDS 6-19 SETUP COMMANDS Page Page 6-22 FRONT PANEL CONTROLS and AUTO FUNCTIONS 6-23 DATA TRANSFER COMMANDS 6-24 6-25 6-26 Page 6-28 INTERFACE COMMANDS 6-29 STATUS REPORTING COMMANDS 6-30 STATUS BYTE DEFINITIONS 6-31 6-32 6-33 EXAMPLE PROGRAM 1 Using Microsoft C (v5.1) with the National Instruments GPIB card on the IBM PC. 6-34 6-35 6-36 Page Page 6-39 6-40 6-41 6-42 PERFORMANCE TESTS Introduction [HARDKEYS] <Softkeys> 7-1 7-2 General Installation 7-3 Necessary Equipment Warm Up The Test Record If A Test Fails Page 7-5 1. Self Tests Page 7-7 2. DC Offset Page 7-9 3. Common Mode Rejection Page 7-11 4. Amplitude Accuracy and Flatness 7-12 7-13 5. Amplitude Linearity 7-14 6. Frequency Accuracy Page 7-17 7. Phase Accuracy Page 7-19 8. Sine Output Amplitude Accuracy and Flatness Page 7-21 9. DC Outputs and Inputs 7-22 10. Input Noise Page SR850 Performance Test Record 1. Self Tests 2. DC Offset Page SR850 Performance Test Record 9. DC Outputs and Inputs (continued) 7-27 SR850 Performance Test Record 9. DC Outputs and Inputs (continued) 10. Input Noise 7-28 SR850 SERVICE 8-1 CAUTION CIRCUIT BOARDS Page 8-3 Adjusting the DC Offset and Common Mode Rejection 8-4 8-5 8-6 Adjusting the Notch Filters 8-7 Page CIRCUIT DESCRIPTION CAUTION VIDEO DRIVER AND CRT CIRCUIT BOARDS 9-1 Page CPU BOARD 9-3 9-4 POWER SUPPLY BOARD 9-5 Page DSP LOGIC BOARD 9-7 9-8 ANALOG INPUT BOARD 9-9 9-10 9-11 9-12 9-13 DSP Logic Board Parts List 9-14 9-15 9-16 9-17 9-18 9-19 9-20 Analog Input Board Parts List 9-21 9-22 9-23 9-24 9-25 9-26 9-27 CPU Board Parts List 9-28 9-29 9-30 9-31 9-32 Chassis Assembly Parts List 9-33 9-34 9-35 Miscellaneous Parts List