Stanford Research Systems SR844 User Manual Download Page 38

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2-8

SR844 Basics

SR844 RF Lock-In Amplifier

The Functional SR844

The functional block diagram of the SR844 RF Lock-In Amplifier is shown below. A
short description of each block follows .

X Ref

Signal Input

1 M

Ω

PreAmp

200 MHz

LPF

Ω

20 dB

Attenuator

20 kHz

HPF

20 dB Gain

SR844 Block Diagram

Mixer

180 kHz

LPF

Variable IF

Gain

Anti-alias

Filter

A to D

Converter

DSP

D to A

Converter

Front Panel

Outputs

CH1

CH2

X-IF

Y-IF

20 MHz XTAL

Reference

Auto-threshold

Comparator

External

Reference

Input

Ω

Synthesizer

Phase

Comparator

Loop Filter

Error

Amplifier

200-400 MHz

VCO

Divider Chain

Int Ref

Ext Ref

Y Ref

I. F. Section

RF Signal Path

Reference Channel

Ref

IF Chop

Summary of Contents for SR844

Page 1: ...RF Lock In Amplifier 1290 D Reamwood Avenue Sunnyvale California 94089 Phone 408 744 9040 Fax 408 744 9049 email infor thinkSRS com www thinkSRS com Copyright 1997 2007 2013 by SRS Inc All Rights Rese...

Page 2: ...d against defects in materials and workmanship for a period of one 1 year from the date of shipment Service For warranty service or repair this product must be returned to a Stanford Research Systems...

Page 3: ...the fuse holder Line Fuse Verify that the correct line fuse is installed before connecting the line cord For 100V 120V use a 1 Amp fuse and for 220V 240V use a 1 2 Amp fuse Line Cord The SR844 has a d...

Page 4: ...mbols that may be found on SRS products Symbol Description Alternating current Caution risk of electric shock Frame or chassis terminal Caution refer to accompanying documents Earth ground terminal Ba...

Page 5: ...SR844 2 8 RF Signal Input Path 2 9 Reference Channel 2 10 I F Section 2 11 Inside the DSP 2 12 Analog Outputs and Scaling 2 15 What is Dynamic Reserve 2 17 Sources of Error 2 19 Using the SR844 as a...

Page 6: ...e Program 4 34 Chapter 5 Testing Getting Ready 5 3 Self Test 5 5 Amplitude Response 5 7 Phase Response 5 9 Frequency Accuracy 5 11 Ref Out Amplitude 5 13 DC Outputs and Inputs 5 15 Input Noise 5 17 SR...

Page 7: ...x Input Noise 1 M Input 25 kHz f 200 MHz 5 nV Hz typical 8 nV Hz max Dynamic Reserve 60 dB expand off Reference External Reference Input 25 kHz to 200 MHz Impedance 50 or 10 k 40 pF Level 0 7 Vpp digi...

Page 8: ...c Other Harmonics and Sub harmonics 40 dBc Spurious Responses 10 dBc Ref 2 IF 23 dBc Ref 4 IF 30 dBc otherwise Displays Channel 1 Channel 2 Reference Type 4 digit LED 4 digit LED 4 digit LED Displayed...

Page 9: ...lution 1 3 mV Bandwidth 3 kHz Outputs 2 Range 10V Resolution 1 mV Environmental Conditions Operating Temperature 10 C to 40 C Specifications apply over 18 C to 28 C Relative Humidity 90 Non condensing...

Page 10: ...viii SR844 RF Lock In Amplifier...

Page 11: ...For all of the tutorials it is expected that you have installed the instrument with the line voltage setting appropriate to the AC power available If you have not done so please see the section Line...

Page 12: ...1 2 Getting Started SR844 RF Lock In Amplifier...

Page 13: ...e processor RAM BATT TEST PASS refers to a test of the battery backed up memory PROG TEST PASS follows a test of the instrument program ROM DSP TEST PASS refers to the Digital Signal Processor DSP RCA...

Page 14: ...ghly 50 meters of BNC cable Your BNC cable is probably a lot shorter than this so the signal input is close to being in phase with the reference 6 Check the readings on the front panel displays Press...

Page 15: ...tory preset configuration is Internal Reference mode shown by the INTERNAL LED at 1 00 MHz shown on the Reference display The time constant is 100 ms shown by the time constant indicators 1 100 and ms...

Page 16: ...ly less than R amplitude 4 Press Shift then Phase to perform AutoPhase This adjusts the reference phase inside the instrument The phase at which the signal is detected changes but Ref Out remains unch...

Page 17: ...Sensitivity This adjusts the sensitivity so that the measured magnitude R is a sizable percentage of full scale The instrument should end up on the 1 V scale and the displays showing their previous va...

Page 18: ...filter rolloff can be 6 12 18 or 24 dB oct With 24 dB oct rolloff it takes about 12 time constants to get within 1 of the final reading Remember both the time constant and filter slope affect the out...

Page 19: ...ecall PRESET to restore factory presets The factory preset configuration is 1 Vrms sensitivity 100 ms 12 dB oct time constant Internal Reference at 1 00 MHz Signal Input 50 3 Use the knob to adjust th...

Page 20: ...isplay on CH1 should read within a few dB of 0 dBm 0 224 Vrms depending upon the amplitude setting of the signal generator 11 Adjust the signal generator amplitude to half the original amplitude 100 m...

Page 21: ...ay need to adjust the SR844 sensitivity so that the signal amplitude R is a sizable fraction of the full scale range If the REF IN signal is noisy or too small the SR844 may not be able to lock The re...

Page 22: ...rence at 1 00 MHz Signal Input 50 3 Connect REF OUT on the front panel to the SIGNAL IN with the BNC cable The SR844 reference output 1 0 Vpp nominal square wave into 50 is within the unit s measureme...

Page 23: ...eft of the CH1 OUTPUT connector X Y and R may all be offset and expanded independently Since Channel 1 is displaying X the Offset On Off Auto and Modify and Expand keys below the Channel 1 Display set...

Page 24: ...set Yoffset and the signal input Since the vector Xoffset Yoffset is used to cancel a real signal at the input Xoffset and Yoffset are always turned on and off together Turning either X or Y offset on...

Page 25: ...ll scale The Expand indicator turns on at the bottom of the Channel 1 display to indicate that the displayed quantity has been expanded The output voltage should now be 0 54 V 1 0 V 0 44 10 10V 10 V o...

Page 26: ...ed by XY offsets At the present time Y is offset to zero and X is offset to 100 mV The resultant R is 100 mV and the CH1 display should read about 0 1 V Expand is off since the display quantity R has...

Page 27: ...he CH1 ROffs indicator turns off and the displayed R returns to 0 1 V The XYOffs indicator remains on because XY offsets are still on 17 Press Display four times to return to X display The CH1 display...

Page 28: ...b selects the setup number shown in the CH2 display 5 Press Save again The second time Save is pressed completes the operation The message DONE is appears briefly in the Reference display Any other ke...

Page 29: ...X OUT 1 on the Reference display The default value is 0 000 V 4 Use the knob to adjust the level to 10 000 V Change the output to 10 V The DVM should read very close to 10 000 V 5 Use the knob to adju...

Page 30: ...000V AUX IN 2 prior to time constant filtering Ratio mode is fully explained in Chapter 3 CH 1 Display and Output Another application of the AUX IN voltages is to provide a second demodulation someti...

Page 31: ...Filter 2 11 Gain Stages 2 11 Anti Aliasing Filter 2 11 16 Bit ADC 2 11 Inside the DSP 2 12 Inputs 2 12 Demodulators 2 12 Phase Adjust 2 12 Offsets 2 13 Ratio 2 13 Time Constant Filters 2 13 R dBm Comp...

Page 32: ...2 2 SR844 Basics SR844 RF Lock In Amplifier...

Page 33: ...the patience to wait for several time constants Using a 1 Hz detection bandwidth the output noise will be only 3 V 3 nV Hz 1 Hz 1000 which is considerable less than the amplified signal of 1 mV The si...

Page 34: ...VM2 FILT VM1 FILT 2 8 In Phase Component X R cos R I 2 9 Quadrature Component Y R sin R I 2 10 Units RMS or Peak Lock in amplifiers as a general rule measure the input signal in Volts rms When the SR8...

Page 35: ...ays the case for the signal of interest in a lock in measurement However there is always noise and often times spurious signals at other frequencies It is instructive to follow such a signal through a...

Page 36: ...put is at the chop frequency and not at DC While its amplitude may still be small the post mixer amplifier can now be AC coupled eliminating problems of DC offset and drift completely The chop frequen...

Page 37: ...ce It is not necessary to provide an external reference to the SR844 The SR844 contains a digital frequency synthesizer that may be used as an internal reference source This is a convenient feature in...

Page 38: ...ttenuator 20 kHz HPF 20 dB Gain SR844 Block Diagram Mixer 180 kHz LPF Variable IF Gain Anti alias Filter A to D Converter DSP D to A Converter Front Panel Outputs CH1 CH2 X IF Y IF 20 MHz XTAL Referen...

Page 39: ...enuated at the input and not measured accurately by the SR844 Even a 50 source impedance forms a 106 MHz filter at the 1 M input 200 MHz Low Pass Filter This passive filter removes signal components a...

Page 40: ...49 kHz by 3 4 12 or 16 The chopping frequency is between 2 3 kHz for time constants of 1 ms and above and between 8 12 kHz for 100 and 300 s time constants as well as No Filter 20 MHz Reference Synth...

Page 41: ...k signals The instrument sets the variable gain appropriate to the IF close dynamic reserve mode and overall sensitivity Anti Aliasing Filter Digital sampling causes aliasing where analog signals at h...

Page 42: ...waveform which converts the X IF and Y IF signals back to DC The advantage of demodulating inside the DSP is to eliminate the DC output errors of analog mixers Phase Adjust The two demodulated signals...

Page 43: ...Turning either offset on or off turns on or off both offsets Auto offsetting either X or Y performs auto offset on both quantities These statements are true even if only one of the quantities X or Y...

Page 44: ...and Y is between 48 and 96 kHz for time constant filter slopes of 6 and 12 dB oct as well as No Filter The X and Y update rate for 18 and 24 dB oct filtering is 4 times slower or 12 24 kHz The update...

Page 45: ...the gain distribution while keeping the overall gain constant The SR844 considers 10 Vdc to be full scale for any output proportional to simply X Y or R Values of X Y and R are always rms values Noise...

Page 46: ...anded output scales are 2 dB V and 0 2 dB V for x10 and x100 expands The phase output may also be expanded on CH2 The expanded output scales are 1 8 V and 0 18 V for x10 and x100 expands The phase out...

Page 47: ...ies 1 gain and 2 bandwidth narrowing to the input signal and it does so in several stages Depending on their frequency different interfering signals are rejected at different points An interfering sig...

Page 48: ...IF gain and the best output signal to noise Normal is once again somewhere in between The maximum allowable IF gain is proportional to sensitivity x RF gain 1 up to a maximum of 50 dB Choosing the Wid...

Page 49: ...frequency These outputs are indistinguishable from the output due to a signal at the reference frequency Square Wave Response The first class of spurious responses are harmonics of the reference frequ...

Page 50: ...t ideal and signals at frequencies other than the reference can cause DC outputs from the final chopping operation The spurious responses are typically 10 dB at a frequency offset of 2fC dropping to 3...

Page 51: ...V A A A A A A 300 nV A A A A A A 100 nV A A A A A A Clearly the Low Noise reserve setting should be used whenever possible For sensitive measurements the Low Noise reserve can provide 60 dB or more of...

Page 52: ...a by AUX IN 1 and then low pass filtering the result If AUX IN 1 is 1 V the DSP is effectively demodulating the 100 Hz output and averaging it In order to get accurate measurements of the 100 Hz modul...

Page 53: ...measured noise Therefore the SR844 uses a simplified algorithm to estimate the X or Y noise The moving average of X is computed over some past history and subtracted from the present value X to get th...

Page 54: ...2 24 SR844 Basics SR844 RF Lock In Amplifier settling time is required If the sensitivity or other measurement parameter is changed then the noise estimate will need to settle to the correct value...

Page 55: ...E rms 0 91 nV ENBW Shot Noise Electric current has noise due to the finite nature of the charge carriers There is always some non uniformity in the electron flow which generates noise in the current T...

Page 56: ...which noise sources are coupled into the signal path Capacitive coupling An RF or AC voltage from a nearby piece of apparatus can couple to a detector via a stray capacitance Although CSTRAY may be v...

Page 57: ...nging current in a nearby circuit gives rise to a changing magnetic field which induces an EMF d B dt in the loop connecting the detector to the experiment This is like a transformer with the experime...

Page 58: ...xperiment or cables due to vibrations for example can result in electrical noise at the lower end of the SR844 s operating frequency range For example consider a coaxial cable connecting a detector to...

Page 59: ...ront Panel Connectors 3 5 Rear Panel Connectors 3 6 Factory Preset Values 3 7 Signal Input 3 8 Time Constants 3 11 Sensitivity 3 13 CH1 Display and Output 3 15 CH2 Display and Output 3 21 Reference Se...

Page 60: ...3 2 Operation SR844 RF Lock In Amplifier...

Page 61: ...HASE AxOut1 FREQ AxOut2 Offs REFERENCE OVLD XY Offs Offset Ratio V mV DEG V dBm nV pV Expand OVLD XY Offs R Offs V mV V dBm nV pV Expand 1 V rms 5 V DC AC MAX UNDERFLOW REL 1m 10m 100m 1 127 107 87 67...

Page 62: ...ously to toggle the key click on and off Keypad Test To test the keypad press the Ref Z In Source keys together The CH1 and CH2 displays will read Pad Code and a number of LED indicators will be turne...

Page 63: ...lay Press any key other than Phase 90 or Zero to exit this test mode Display Off Operation Enter the Display Test mode as explained above Press Phase until no LED s are lit The SR844 is still operatin...

Page 64: ...nd fuse RS 232 The RS 232 connector is configured as a DCE transmit on pin 3 receive on pin 2 The baud rate and parity are set with the Setup key To connect the SR844 to a standard PC compatible seria...

Page 65: ...either remote interface The factory preset values are Reference Phase Scan Rel Reference Source Internal Scan Start 100 kHz Internal Frequency 1 00 MHz Scan Stop 100 MHz Input Impedance 50 Number of...

Page 66: ...n stages to the mixers Important The 1 M input should only be used if the source impedance is much greater than 50 The bandwidth of the 1 M input is limited by its 30 pF input capacitance and the sour...

Page 67: ...e manual changes The AUTO indicator is on while this function executes RF OVLD The RF OVLD indicator shows that the RF input is overloaded This overload occurs in the RF signal path before the mixers...

Page 68: ...4 RF Lock In Amplifier Sig Z In 50 1 M Wide Reserve HIGH NORMAL LOW NOISE HIGH NORMAL LOW NOISE 1 V 20 dB 20 dB 20 dB 20 dB 20 dB 20 dB 300 nV 20 dB 20 dB 20 dB 20 dB 20 dB 20 dB 100 nV 20 dB 20 dB 20...

Page 69: ...d s ms s ks Filter Slope 0 to 4 stages of output low pass filtering may be selected These provide up to 24 dB octave of attenuation for AC signals at the output Each filter stage contributes 6 dB octa...

Page 70: ...e 1 response time of the instrument is approximately 2 sample periods or about 20 s best case The update rate for R and remains 12 24 kHz even in the No Filter mode In addition to the update rate the...

Page 71: ...the 1 M input AUTO Shift SensUp This key sequence automatically adjusts the sensitivity based on the detected signal magnitude the instrument reserve settings and any overload conditions This functio...

Page 72: ...best possible output signal to noise and should be used whenever possible AUTO Shift Close Reserve This key sequence automatically selects the Close Dynamic Reserve mode This function will execute onc...

Page 73: ...n phase with the reference The reference phase may be adjusted see the section on Reference Phase later in this chapter for more information R V This is the magnitude of the input signal measured in V...

Page 74: ...re details The X output updates 4 times slower when 18 and 24 dB oct filtering is used The digital display is always updated at a 2 Hz rate The bar graphs are updated at 64 Hz Display quantities may b...

Page 75: ...e displayed quantity is affected by X and Y offsets Xoffset and Yoffset are applied before R and are calculated Thus the XYOffs indicator will be on if the display is showing R and XY offsets are on R...

Page 76: ...Off The instrument has a single ratio mode which applies to both X and Y The CH2 AUX IN 1 and AUX IN 2 indicators follow the CH1 indicators In Ratio Mode the non ratioed quantities are not available...

Page 77: ...ify variations of the measured quantity about a nominal value Remember in order to expand a quantity it must be less than 10 10 or 1 100 of full scale Example Suppose the X component of the input is 1...

Page 78: ...indicator above the CH1 OUTPUT BNC indicates that the analog output is overloaded greater than 10 5 V The OVLD indicator within the CH1 display indicates that the display has overloaded The normal ran...

Page 79: ...currently displayed quantity Quantity Description Y This is the component of the input signal in quadrature with the reference The reference phase may be adjusted see the section on Reference Phase l...

Page 80: ...gn is unchanged by the ratio The phase will change by 180 if the ratio input is negative Note 3 The detection phase may be modified by adjusting the Reference Phase this can be used to adjust or null...

Page 81: ...statements are true even if only one of the quantities X or Y is currently being displayed Use the Reference Phase controls to adjust the measured and displayed phase of the input signal This is discu...

Page 82: ...rmitted The SR844 has a single ratio mode that is common to both channels The control for the ratio mode is the Ratio key in the Channel 1 Display section The instrument s ratio mode will be applied t...

Page 83: ...xpanding Y will not affect R and Expand is applied after offsets and ratios The typical use of the Expand function is in conjunction with the Offset function to magnify variations of the measured quan...

Page 84: ...display and Y analog out OVLD There are 2 overload indicators for CH2 The OVLD indicator above the CH2 OUTPUT BNC indicates that the analog output is overloaded greater than 10 5 V The OVLD indicator...

Page 85: ...ection frequency PRECISE FREQ Precise Reference Frequency Only in Internal Reference Mode Displays the reference frequency on the Channel 2 and Reference Displays with extra precision I F IF Frequency...

Page 86: ...n internal mode may be slightly different within 1 in the 4th digit I F Shift AuxOut This key sequence shows the IF frequency on the Reference Display See Chapter 2 Sources of Error for more informati...

Page 87: ...a measured phase of the input signal that is close to zero Note that if the measured phase of the input signal is not settled or is noisy at the time Shift Phase is pressed the measured phase will not...

Page 88: ...ocking The SR844 will lock to other amplitudes with possible degradation in phase accuracy and jitter OUT OF RANGE This indicator is on whenever the External Reference input is out of the operating fr...

Page 89: ...where n is the last used setup buffer Another setup buffer 1 9 may be selected using the knob The Reference display shows YES if buffer n is in use and NO is it is empty A second press of the Recall...

Page 90: ...e knob to select either GPIB or R232 for the output interface ADDRESS Use the knob to select a GPIB address for the SR844 BAUD Use the knob to select a RS232 baud rate from 300 to 19200 baud PARITY Us...

Page 91: ...ors since the REMOTE indicator is on in both cases If the Local key does not return the unit to the Local state the unit is probably in the Local Lockout state There are three ways to get out of the L...

Page 92: ...nterpolated frequencies are rounded to the resolution of the internal frequency source The SCAN MODE indicator is on while a scan is in progress Use the Scan Set key to setup a scan Scan setup is not...

Page 93: ...ct are still applied to the measurement Use the CLEAR ALL key Shift Rel Mode to clear all stored Rel Configurations and Values and CLEAR ONE Shift Start Step to clear the Rels at the current scan freq...

Page 94: ...er keypress exits the Scan Mode while remaining at the Stop frequency The SCAN MODE and SCAN DONE indicators both turn off N 2nd The next keypress begins another scan just like the 1st keypress above...

Page 95: ...ed Rel Values and Configuration once again Changing frequency scan parameters clears all stored Rel Values Use the CLEAR ALL key Shift Rel Mode to clear all stored Rel Configurations and Values and CL...

Page 96: ...is applied as the R dBm offset The stored Rel Value is applied as the Reference Phase there is no phase offset Offset indicators within the CH1 and CH2 displays are turned on as appropriate as well a...

Page 97: ...erminated to the input of the DUT The DUT output should be connected to the SIGNAL IN of the SR844 Now by pass the DUT leave as much of the apparatus in place as possible It is important to use the sa...

Page 98: ...y does not have any stored Rel Values as indicated by XY READY or R dBm the current configuration and offsets remain in effect The REL indicator is off in this case The stored XY Rel Values are applie...

Page 99: ...t signal In the case of a substantial signal change it may be necessary to perform the Auto Sensitivity function again or adjust the sensitivity reserve manually Auto Sensitivity takes more time to co...

Page 100: ...y range in octave bands Users can check the IF frequency to determine whether the instrument is at the high end of an octave band or the low end of the next band At the high end of an octave the IF fr...

Page 101: ...ation which differs from the current one The R dBm indicator turns on indicating that R Rel Values are stored for this scan frequency 2F Mode Shift Source This key sequence toggles 2F harmonic detecti...

Page 102: ...3 44 Shift Functions SR844 RF Lock In Amplifier...

Page 103: ...ommands 4 11 Signal Input Commands 4 12 Gain and Time Constant Commands 4 13 Display and Output Commands 4 15 Aux Input and Output Commands 4 17 Setup Commands 4 18 Auto Functions 4 20 Scan and Rel Fu...

Page 104: ...r of Hz PHAS x 4 11 Set Query the Reference Phase to x degrees APHS 4 20 Perform AutoPhase function REFZ i 4 11 Set Query the Reference Input impedance to 50 0 or 10 k 1 Signal Input WRSV i 4 12 Set Q...

Page 105: ...Remote mode to Off 0 or On 1 KCLK i 4 18 Set Query the Keyclick to Off 0 or On 1 ALRM i 4 18 Set Query the Alarms to Off 0 or On 1 SSET i 4 18 Save current settings to Buffer i 1 9 RSET i 4 18 Recall...

Page 106: ...bin j 0 from Display ch 1 2 buffer in non normalized binary floating point FAST i 4 28 Set Query Fast Data Transfer mode to Off 0 or On 1 Fast mode will transfer binary X and Y every sample during a...

Page 107: ...M RAM memory test failed 3 LIA Enabled bit in LIA status set 3 FPG FPGA test failed 4 MAV Interface output buffer not empty 4 ROM ROM memory test failed 5 ESB Enabled bit in Standard Event status set...

Page 108: ...4 6 Index of Commands SR844 RF Lock In Amplifier...

Page 109: ...l pin 5 is an output indicating that the SR844 is ready while the DTR signal pin 20 is an input that is used to control the SR844 s data transmission If desired the handshake pins may be ignored and a...

Page 110: ...e it If either buffer overflows both buffers are cleared and an error reported The present value of a particular parameter may be determined by querying the SR844 for its value A query is formed by ap...

Page 111: ...s in progress After the IFC bit becomes set signaling the completion of the command then the ERR or ESB bits may be checked to verify successful completion of the command If the RS232 interface is use...

Page 112: ...y including the question mark after the command mnemonic and omitting the queried parameter from the command The query parameters shown in are NOT sent with a query The query returns the value of thes...

Page 113: ...sets the frequency of the internal reference oscillator This command is allowed only if the Reference Mode is Internal The parameter f is a real number that specifies the frequency in Hz The value of...

Page 114: ...0 Normal i 1 or Low Noise minimum wide reserve i 2 AWRS The AWRS command performs the Auto Wide Reserve function This command is the same as pressing Shift WideReserveDown AWRS automatically sets the...

Page 115: ...unction does nothing if the time constant is greater than 1 s Check the Interface Ready bit bit 1 in the Serial Poll Status to determine when the command is finished CRSV i The CRSV command sets or qu...

Page 116: ...mand resets the Elapsed Time counter to zero while the SETL query returns the Elapsed Time as a real number in units of the current Time Constant since either the last SETL command or since the Settle...

Page 117: ...aling is applied before the Time Constant filters and applies to X Y R Xnoise and Ynoise The DRAT i command sets the ratio mode as listed below i Ratio 0 none 1 AUX IN 1 2 AUX IN 2 FPOP ch i The FPOP...

Page 118: ...return zero AOFF ch q The AOFF ch q command automatically offsets the chosen quantity to zero The quantity is specified by its display channel ch and quantity q as per the table above Both parameters...

Page 119: ...lects an Aux Input and is required The Aux Input voltages are returned in units of Volts The resolution is 1 3 mV This is a query only command AUXO i x The AUXO command sets or queries the Aux Output...

Page 120: ...g buffer i 1 i 9 The setting buffers are retained when the power is turned off RSET i The RSET i command recalls the instrument setup from setting buffer i 1 i 9 Interface parameters are not changed w...

Page 121: ...ase 16 CH1 Display 44 90 17 Ratio 45 Phase Zero 18 CH1 Expand 48 Shift 19 CH1 Output 49 Freq 20 CH1 Offset On Off 50 Ref Z In 21 CH1 Offset Auto 51 Ref Source 24 CH2 Display 57 Aux Out 26 CH2 Expand 5...

Page 122: ...nt is long This function does nothing if the time constant is greater than one second Check the Interface Ready bit bit 1 in the Serial Poll Status to determine when the command is finished APHS The A...

Page 123: ...ot be set while a scan is in progress SMOD i The SMOD command sets and queries the current scan point SMOD i moves to point i 1 i N in the scan where N Number of Scan Points Use SMOD to move from scan...

Page 124: ...w often points are added to the storage buffer Both displays are sampled at the same rate and at the same times In addition to the internal sample rates sampling can be triggered by a remote TRIG comm...

Page 125: ...fer data Aliasing Effects In any sampled data stream it is possible to sample a high frequency signal such that it will appear to be a much lower frequency This is called aliasing Aliasing occurs when...

Page 126: ...SRAT14 then receipt of this command causes data to be sampled and stored to both the Channel 1 and Channel 2 buffers within 2 ms actually on the next 512 Hz clock tick The command is ignored if the Da...

Page 127: ...applied just like the display SNAP i j k l m n The SNAP command returns the values of up to six parameters at a single instant For example SNAP is a way to query values of X and Y or R and recorded a...

Page 128: ...k The TRCA command queries the points stored in the Display ch buffer The values are returned as ASCII floating point numbers in the units of the display Multiple points are separated by commas and th...

Page 129: ...urned in non normalized floating point format in the units of the trace There are four bytes per point Multiple points are not separated by any delimiter The bytes cannot be read directly into a float...

Page 130: ...nsfers 512 Hz maximum It is important that the receiving interface be able to keep up with the transfers Offsets Ratios and Expands are included in the values of X and Y The values of X and Y are tran...

Page 131: ...te command execution and keyboard input are allowed In the Remote state remote command execution is allowed but the keyboard and knob are locked out except for the Local key which returns the SR844 to...

Page 132: ...the Standard Event Enable register The ESE i command queries the value 0 or 1 of bit i PSC i The PSC command sets the value of the Power On Status Clear bit If i 1 the power on status clear bit is se...

Page 133: ...egister has been set 3 LIA An enabled bit in the LIA status register has been set 4 MAV The interface output buffer is not empty 5 ESB An enabled bit in the Standard Event status register has been set...

Page 134: ...has failed 2 RAM The RAM memory test failed 3 FPG FPGA test failed 4 ROM The ROM memory test failed 5 GPB GPIB Fast Data Transfer mode is aborted 6 DSP The DSP test failed 7 MTH An internal math erro...

Page 135: ...ice request from the same status bit is desired the requesting status bit must first be cleared In the case of ERR LIA and ESB bits this means clearing the enabled bits in the ERR LIA and ESB status r...

Page 136: ...n your computer The software interface uses a header file and a link library There is no initialization required for the drivers Use the TEST488 program to test the card installation Use TRTEST to com...

Page 137: ...iaBuf 1600 LIA float buffer ch1 2 ints per point int pLiaBuf 1600 LIA float buffer ch2 2 ints per point float rfBuf 800 IEEE binary buffer ch1 1 float per point float pfBuf 800 IEEE binary buffer ch2...

Page 138: ...0 SEND0 Set sample rate 64 Hz stop at end TxSr844 DDEF1 0 DDEF2 0 Buffers store CH1 X and CH2 Y displays printf Initialization done Change settings here if desired GetSpace Pause to change setup Read...

Page 139: ...0 i 10 i get 64 points 256 bytes 10 times rarray char FastBuf 128 i 64 4 nCount status rarray receives bytes from the interface and puts them into the FastBuf array Each transfer moves 64 points 64 4...

Page 140: ...2 start at bin 0 all points TxGpib sr844 cmd Send cmd and don t wait for IFC ready transmit MLA TALK 8 status Make sr844 the talker rarray char pfBuf nPts 4 nCount status Read directly into a FLOAT ar...

Page 141: ...ASCII IEEE LIA n for i 0 i 10 i printf 3d 14s 14 6E 14 6E n i rAscBuf i rfBuf i xLIA 1 i xLIA translates LIA float format into IEEE floating point Data in rfBuf is already IEEE floats for Ch2 printf C...

Page 142: ...tb do spoll sr844 stb status while stb 2 spoll is the CEC serial poll routine The value of the Serial Poll register is stored in stb Test bit 1 IFC until set if stb 32 If ESB bit set bit 5 in Serial P...

Page 143: ...to voltage y y fscale sens by multiplying by full scale input voltage switch quant case 1 return sqrt x x y y Compute R from X and Y case 2 return atan2 y x 57 2958 Compute theta from X and Y case 3...

Page 144: ...4 42 Example Program SR844 RF Lock In Amplifier...

Page 145: ...Revision 5 3 Preset 5 3 Warm Up 5 3 Test Record 5 3 Necessary Equipment 5 3 Front Panel Display Test 5 4 Keypad Test 5 4 If A Test Fails 5 4 1 Self Tests 5 5 2 Amplitude Response 5 7 3 Phase Response...

Page 146: ...5 2 Performance Tests SR844 RF Lock In Amplifier...

Page 147: ...e To do this press Shift then Recall Warm Up The lock in should be turned on and allowed to warm up for at least an hour before any tests are performed The self test does not require any warm up perio...

Page 148: ...l read Pad Code and a number of LED indicators will be turned on The LED s indicate which keys have not yet been pressed Press all of the keys on the front panel one at a time As each key is pressed t...

Page 149: ...on while holding down the Setup key Check the results of the DATA BATT PROG and DSP tests DATA Performs a read write test to the processor RAM BATT The nonvolatile backup memory is tested Instrument...

Page 150: ...5 6 Performance Tests SR844 RF Lock In Amplifier...

Page 151: ...equivalent One to SIGNAL IN through a feed through 3 dB attenuator Mini Circuits CAT 3 or equivalent We will need 2 feed through 20 dB attenuators Mini Circuits CAT 20 or equivalent for portions of th...

Page 152: ...the SR844 UNLOCK indicator to turn off 3 3 Wait for the CH1 reading to stabilize Record the CH1 reading dBm 4 Add one 20 dB attenuator at the SIGNAL IN The total attenuation at the SIGNAL IN is now 23...

Page 153: ...NAL IN through a feed through 3 dB attenuator Mini Circuits CAT 3 or equivalent Set the RF synthesizer to Frequency 100 0 kHz Amplitude 9 0 dBm Modulation OFF The synthesizer output 9 0 dBm the splitt...

Page 154: ...n the table below perform steps 3 1 through 3 2 Test Frequencies 100 kHz 300 kHz 1 MHz 3 MHz 10 MHz 30 MHz 100 MHz 3 1 Set the RF synthesizer to the frequency in the table 3 2 Wait for the SR844 UNLOC...

Page 155: ...Press the keys in the following sequence Source Switch to EXTERNAL Reference mode Shift then Freq Precise Freq Display the Precise Frequency on the CH2 and Reference displays 3 For each frequency in t...

Page 156: ...5 12 Performance Tests SR844 RF Lock In Amplifier...

Page 157: ...ies Procedure 1 Press Shift then Recall to restore the factory preset instrument settings 2 Press the keys in the following sequence CH1 Display twice Set the CH1 display to R dBm 3 REF OUT amplitude...

Page 158: ...5 14 Performance Tests SR844 RF Lock In Amplifier...

Page 159: ...H1 or CH2 output to the DVM Set the DVM to the 20 Vdc range 2 2 Press CH1 or CH2 Offset On Off to turn XYOffs on 2 3 Press CH1 or CH2 Offset Modify to see the offset in the Reference display 2 4 For e...

Page 160: ...epeat steps 5 1 through 5 3 5 1 Connect AUX OUT 1 to AUX IN 1 or AUX IN 2 5 2 Press CH1 or CH2 Display until the display shows AUX IN 1 or AUX IN 2 5 3 For the same table of voltages as in 3 3 above r...

Page 161: ...y preset instrument settings 2 Press the keys in the following sequence Sensitivity Down until the sensitivity is 300 nV CH1 Display three times Set the CH1 display to Xnoise Close Reserve once until...

Page 162: ...5 18 Performance Tests SR844 RF Lock In Amplifier...

Page 163: ...2 0 dBm 100 MHz 2 25 dBm 2 25 dBm 200 MHz 2 25 dBm 2 25 dBm Sensitivity Frequency Lower Limit CH1 Reading dBm Upper Limit 30 mV 100 kHz 22 5 dBm 17 5 dBm 300 kHz 22 5 dBm 17 5 dBm 1 MHz 22 5 dBm 17 5...

Page 164: ...tude Accuracy and Flatness Frequency Lower Limit CH1 Reading dBm Upper Limit 100 kHz 5 6 dBm 9 6 dBm 300 kHz 5 6 dBm 9 6 dBm 1 MHz 5 6 dBm 9 6 dBm 3 MHz 4 6 dBm 8 6 dBm 10 MHz 3 6 dBm 7 6 dBm 30 MHz 2...

Page 165: ...V 5 000 V 5 010 V 4 990 V 0 000 V 0 005 V 0 005 V 5 000 V 4 990 V 5 010 V 10 000 V 9 990 V 10 010 V Input Voltage Lower Limit CH1 Reading V Upper Limit AUX IN 1 10 000 V 10 200 V 9 800 V 5 000 V 5 20...

Page 166: ...5 22 SR844 Test Record SR844 RF Lock In Amplifier...

Page 167: ...Chop and Mix Board 6 13 84IFN I F and Noise Board 6 15 84XRF External Reference Board 6 17 84DVC Divider Chain Board 6 20 84DSP Digital Signal Processing Board 6 22 Parts Lists 6 25 CPU and Power Supp...

Page 168: ...6 2 Circuitry Parts Lists and Schematics SR844 RF Lock In Amplifier...

Page 169: ...serviced by qualified personnel only There are no user serviceable parts inside Check the LED at the front right corner of the CPU and power supply board The unit is safe only if the LED is off If th...

Page 170: ...nd power supply The Keypad board 844K holds the front panel indicators and keypad The Display board 844S holds the digital readout displays The Rear Panel board 844RTO holds the rear panel BNC connect...

Page 171: ...ing and gain includes ADC Reference 84XRF external reference input and PLL Divider 84DVC reference frequency divider chain Digital Signal Processor 84DSP processing and DC analog inputs and outputs Th...

Page 172: ...t are then downloaded to the DSP doing offset and phase calculations and also computing miscellaneous functions such as Xnoise and Ynoise U201 U203 are latches for the 186 address lines U204 U205 are...

Page 173: ...terrupt and at the same time read the knobs The speaker is controlled by signals TIMER1 from the 186 which is a square wave that sets the frequency of sound to be produced and SPKR_EN which turns the...

Page 174: ...k of the board and the taller LEDs on the front of the board Document Number Sheet Schematic 844S1 1 Display Drivers 844S2 2 Display LEDs Data lines control signals and power all come from the CPU Pow...

Page 175: ...e knob is an optical encoder that is read directly by the host 186 processor It requires no support circuitry on 844S Connectors J1 and J2 distribute the strobe LED row and Key row signals to the 844K...

Page 176: ...and the rest of the instrument b the Synthesizer used in internal reference mode c the Range Select circuitry Document Number Sheet Schematic MBDMAIN 1 84MBD Main MBDXRF 2 84XRF Power Connectors MBDD...

Page 177: ...he signal control bits are in U810 the I F control bits are in U812 and the rest of the control bits are distributed among the registers The digital outputs go through resistors for isolation Many out...

Page 178: ...e clock pulse too soon this delay ensures that the clock to U849 is not a runt pulse U848 also writes the loop filter bits to 84XRF these bits are determined by internal logic from the range bits when...

Page 179: ...pensation at low and high frequencies respectively Relay S150 switches the signal between a straight through path and one containing 20 dB gain U150 The components R150 151 and C150 provide impedance...

Page 180: ...OR ed by U708 when the chop A input is low the Q output of U708 is equal to the reference frequency B input When the chop A input is high the Q output is the inverse of the B input Thus the output of...

Page 181: ...amplifier is biased to of the supply voltage by R769 and R770 and the capacitors Z769 E769 hold the common node stable R768 controls the operating current of the mixer The amplified mixer output is fi...

Page 182: ...er on the front panel The AAF is always connected to U403B but the unfiltered line is disconnected by switch U405A when not in use in order to eliminate cross talk U410A is a summing amplifier that su...

Page 183: ...592 allow the inputs to be shifted to this level NOI CLK is a short TTL pulse also at FS coming from the DSP board U477A synchronizes the edges of 24K the comparator output to the NOI CLK pulse The o...

Page 184: ...be the same voltages as are on the raw input signal The other half of U216 U216B is an operational transconductance amplifier OTA that operates as a difference amplifier The voltage at U216 8 is propo...

Page 185: ...s are selected depending on the control bits LF1 0 as shown below LF1 LF0 Comparison Frequency Range Upper Input Arm Upper Feedback Arm Lower Input Arm Lower Feedback Arm 0 0 25kHz 100kHz N342C D C352...

Page 186: ...all instrument operations are clocked by signals derived from the reference frequency The divider chain takes the VCO output 200 400 MHz and uses flip flops and counters to generate clock signals at 1...

Page 187: ...erence frequency in normal mode and is twice the reference frequency in 2F mode Range 2 3 4 5 6 7 8 9 10 11 12 13 14 RANG0 0 0 0 0 0 0 1 1 1 1 1 1 1 RANG1 0 0 1 1 1 1 0 0 0 0 1 1 1 RANG2 1 1 0 0 1 1 0...

Page 188: ...quired both by the Chop circuit on 84CMX and by the FPGA on 84DSP The latter is used to generate all the clocks and control signals required for data sampling which occurs at 49 98 kHz 84DSP Digital S...

Page 189: ...ncy no hysteresis is required 2 49K is a synchronous clock which defines the instrument sampling rate it is recovered from low level inputs 49K98D also from 84DVC by comparator U938 R938 provides hyst...

Page 190: ...The FPGA converts the parallel data to serial and sends the serial data to dual D to A converter U920 along with the appropriate control signals R928 and Z923 filter the Channel 2 Y output with a 4 7...

Page 191: ...arts Lists 6 25 SR844 RF Lock In Amplifier Parts Lists Parts lists for all of the circuit boards are listed in the following sections Schematic diagrams follow the parts lists at the end of this manua...

Page 192: ...524 2 2U Capacitor Tantalum 50V 20 Rad C 34 5 00193 542 2 2U MIN Cap Mini Electrolytic 50V 20 Radial C 36 5 00127 524 2 2U Capacitor Tantalum 50V 20 Rad C 101 5 00177 501 30P Capacitor Ceramic Disc 5...

Page 193: ...50V 80 20 Z5U AX C 1044 5 00225 548 1U AXIAL Capacitor Ceramic 50V 80 20 Z5U AX C 1047 5 00225 548 1U AXIAL Capacitor Ceramic 50V 80 20 Z5U AX D 2 3 00391 301 MBR360 Diode D 3 3 00391 301 MBR360 Diod...

Page 194: ...35 4 00067 401 3 9K Resistor Carbon Film 1 4W 5 R 36 4 00067 401 3 9K Resistor Carbon Film 1 4W 5 R 37 4 00034 401 10K Resistor Carbon Film 1 4W 5 R 38 4 00034 401 10K Resistor Carbon Film 1 4W 5 R 39...

Page 195: ...kg U 210 3 00537 340 74HC373 Integrated Circuit Thru hole Pkg U 211 3 00045 340 74HC32 Integrated Circuit Thru hole Pkg U 212 3 00045 340 74HC32 Integrated Circuit Thru hole Pkg U 213 3 00038 340 74HC...

Page 196: ...1 043 4 SHOULDER Washer nylon Z 0 0 00246 043 8 X 1 16 Washer nylon Z 0 0 00316 003 PLTFM 28 Insulators Z 0 0 00477 021 8 32X1 2 Screw Panhead Phillips Z 0 0 00772 000 1 5 WIRE Hardware Misc Z 0 1 000...

Page 197: ...Z5U C 8 5 00219 529 01U Cap Monolythic Ceramic 50V 20 Z5U C 9 5 00219 529 01U Cap Monolythic Ceramic 50V 20 Z5U C 10 5 00219 529 01U Cap Monolythic Ceramic 50V 20 Z5U C 11 5 00219 529 01U Cap Monolyth...

Page 198: ...0547 310 RED COATED LED Coated Rectangular D 52 3 00547 310 RED COATED LED Coated Rectangular D 53 3 00547 310 RED COATED LED Coated Rectangular D 54 3 00547 310 RED COATED LED Coated Rectangular D 55...

Page 199: ...MINI LED Subminiature D 419 3 00575 311 GREEN MINI LED Subminiature D 420 3 00575 311 GREEN MINI LED Subminiature D 421 3 00575 311 GREEN MINI LED Subminiature D 422 3 00575 311 GREEN MINI LED Submin...

Page 200: ...or Female J 4 1 00203 131 12 PIN SI SOCK Connector Female J 5 1 00203 131 12 PIN SI SOCK Connector Female J 6 1 00204 130 36 PIN SI Connector Male J 7 1 00204 130 36 PIN SI Connector Male J 8 1 00205...

Page 201: ...CA3081 Integrated Circuit Thru hole Pkg U 6 3 00064 340 CA3081 Integrated Circuit Thru hole Pkg U 7 3 00548 340 74HCT574 Integrated Circuit Thru hole Pkg U 8 3 00548 340 74HCT574 Integrated Circuit T...

Page 202: ...0 00386 003 BNC BUSHING Insulators Z 0 0 00418 000 CLIP CABLE Hardware Misc Z 0 0 00481 000 BUMPER CORD WRP Hardware Misc Z 0 0 00483 000 FAN GUARD III Hardware Misc Z 0 0 00485 057 GROMMET Grommet Z...

Page 203: ...1 Fabricated Part Z 0 7 00707 709 SR844 2 Lexan Overlay Z 0 7 00709 740 SR844 5 Keypad Conductive Rubber Z 0 7 00790 720 SR844 10 Fabricated Part Z 0 7 00791 709 SR844 12 Lexan Overlay Z 0 7 00798 720...

Page 204: ...00260 544 470U Cap Mini Electrolytic 25V 20 Radial E 67 5 00260 544 470U Cap Mini Electrolytic 25V 20 Radial E 826 5 00260 544 470U Cap Mini Electrolytic 25V 20 Radial F 3 5 00318 569 2 2U T35 Cap Ta...

Page 205: ...p Tantalum SMT all case sizes F 95 5 00318 569 2 2U T35 Cap Tantalum SMT all case sizes F 96 5 00318 569 2 2U T35 Cap Tantalum SMT all case sizes F 97 5 00318 569 2 2U T35 Cap Tantalum SMT all case si...

Page 206: ...d SMT L 2 6 00237 631 FR95 Ferrite bead SMT L 3 6 00237 631 FR95 Ferrite bead SMT L 4 6 00237 631 FR95 Ferrite bead SMT L 7 6 00237 631 FR95 Ferrite bead SMT L 8 6 00237 631 FR95 Ferrite bead SMT L 10...

Page 207: ...esistor network SMT Leadless N 842 4 00911 463 4 7KX4D Resistor network SMT Leadless N 852 4 00910 463 1 0KX4D Resistor network SMT Leadless N 853 4 00910 463 1 0KX4D Resistor network SMT Leadless N 8...

Page 208: ...01407 461 1 Thick Film 5 200 ppm Chip Resistor R 81 4 01407 461 1 Thick Film 5 200 ppm Chip Resistor R 82 4 01053 462 215 Thin Film 1 50 ppm MELF Resistor R 83 4 01053 462 215 Thin Film 1 50 ppm MELF...

Page 209: ...Reg TO 220 TAB Package U 43 3 00715 329 79M05 Voltage Reg TO 220 TAB Package U 48 3 00112 329 7805 Voltage Reg TO 220 TAB Package U 49 3 00764 329 7905 2 Voltage Reg TO 220 TAB Package U 54 3 00112 3...

Page 210: ...pm Chip Resistor V 36 4 01461 461 180 Thick Film 5 200 ppm Chip Resistor V 37 4 01461 461 180 Thick Film 5 200 ppm Chip Resistor Z 0 0 00043 011 4 40 KEP Nut Kep Z 0 0 00104 043 4 NYLON Washer nylon Z...

Page 211: ...Capacitor Ceramic SMT1206 50V 20 Z5U Z 58 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 59 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 63 5 00315 527 1UF Capacitor Ceramic SMT1206...

Page 212: ...V 20 Z5U Z 821 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 822 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 823 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 824 5 00315...

Page 213: ...m 50V 5 40 85c C 164 5 00468 512 056U Cap Stacked Metal Film 50V 5 40 85c C 170 5 00374 552 82P Capacitor Chip SMT1206 50V 5 NPO C 171 5 00374 552 82P Capacitor Chip SMT1206 50V 5 NPO C 172 5 00363 55...

Page 214: ...Board Q 101 3 00601 360 MMBT3904LT1 Integrated Circuit Surface Mount Pkg Q 102 3 00601 360 MMBT3904LT1 Integrated Circuit Surface Mount Pkg Q 103 3 00601 360 MMBT3904LT1 Integrated Circuit Surface Mou...

Page 215: ...4 01575 461 10M Thick Film 5 200 ppm Chip Resistor R 180 4 01117 462 1 00K Thin Film 1 50 ppm MELF Resistor R 184 4 01059 462 249 Thin Film 1 50 ppm MELF Resistor R 185 4 00960 462 23 2 Thin Film 1 5...

Page 216: ...V 20 Z5U Z 164 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 170 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 180 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 186 5 00315...

Page 217: ...trolytic 16V 20 Rad E 749 5 00030 520 2200U Capacitor Electrolytic 16V 20 Rad E 767 5 00041 509 220U Capacitor Electrolytic 50V 20 Rad E 768 5 00030 520 2200U Capacitor Electrolytic 16V 20 Rad E 769 5...

Page 218: ...hick Film 5 200 ppm Chip Resistor R 744 4 01059 462 249 Thin Film 1 50 ppm MELF Resistor R 745 4 01059 462 249 Thin Film 1 50 ppm MELF Resistor R 746 4 01084 462 453 Thin Film 1 50 ppm MELF Resistor R...

Page 219: ...F Resistor X 702 4 00993 462 51 1 Thin Film 1 50 ppm MELF Resistor X 703 4 00993 462 51 1 Thin Film 1 50 ppm MELF Resistor X 704 4 00993 462 51 1 Thin Film 1 50 ppm MELF Resistor X 705 4 00993 462 51...

Page 220: ...5 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 728 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 729 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 730 5 00315 527 1UF Capacitor Cer...

Page 221: ...apacitor Monolythic Ceramic COG 1 C 421 5 00149 545 01U Capacitor Monolythic Ceramic COG 1 C 422 5 00149 545 01U Capacitor Monolythic Ceramic COG 1 C 423 5 00389 552 1500P Capacitor Chip SMT1206 50V 5...

Page 222: ...ll case sizes F 423 5 00318 569 2 2U T35 Cap Tantalum SMT all case sizes F 424 5 00318 569 2 2U T35 Cap Tantalum SMT all case sizes F 425 5 00318 569 2 2U T35 Cap Tantalum SMT all case sizes F 426 5 0...

Page 223: ...ase sizes F 537 5 00318 569 2 2U T35 Cap Tantalum SMT all case sizes J 15 1 00301 131 4 PIN DIF CES Connector Female J 40 1 00290 130 8 PIN DI TSW 07 Connector Male J 41 1 00290 130 8 PIN DI TSW 07 Co...

Page 224: ...01053 462 215 Thin Film 1 50 ppm MELF Resistor R 438 4 01059 462 249 Thin Film 1 50 ppm MELF Resistor R 439 4 00993 462 51 1 Thin Film 1 50 ppm MELF Resistor R 440 4 01133 462 1 47K Thin Film 1 50 ppm...

Page 225: ...1141 462 1 78K Thin Film 1 50 ppm MELF Resistor R 497 4 01175 462 4 02K Thin Film 1 50 ppm MELF Resistor R 498 4 01305 462 90 9K Thin Film 1 50 ppm MELF Resistor R 500 4 01001 462 61 9 Thin Film 1 50...

Page 226: ...62 215 Thin Film 1 50 ppm MELF Resistor R 548 4 01124 462 1 18K Thin Film 1 50 ppm MELF Resistor R 549 4 01124 462 1 18K Thin Film 1 50 ppm MELF Resistor R 550 4 01124 462 1 18K Thin Film 1 50 ppm MEL...

Page 227: ...tegrated Circuit Surface Mount Pkg U 475 3 00724 360 LF353 Integrated Circuit Surface Mount Pkg U 476 3 00753 360 4053 Integrated Circuit Surface Mount Pkg U 477 3 00742 360 74HC74 Integrated Circuit...

Page 228: ...k Film 5 200 ppm Chip Resistor V 527 4 01461 461 180 Thick Film 5 200 ppm Chip Resistor V 530 4 01461 461 180 Thick Film 5 200 ppm Chip Resistor V 531 4 01461 461 180 Thick Film 5 200 ppm Chip Resisto...

Page 229: ...V 20 Z5U Z 491 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 492 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 493 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 494 5 00315...

Page 230: ...206 50V 5 NPO C 316 5 00387 552 1000P Capacitor Chip SMT1206 50V 5 NPO C 317 5 00387 552 1000P Capacitor Chip SMT1206 50V 5 NPO C 340 5 00298 568 01U Cap Ceramic 50V SMT 1206 10 X7R C 341 5 00298 568...

Page 231: ...antalum SMT all case sizes F 322 5 00470 569 2 2U T16 Cap Tantalum SMT all case sizes F 330 5 00470 569 2 2U T16 Cap Tantalum SMT all case sizes F 331 5 00318 569 2 2U T35 Cap Tantalum SMT all case si...

Page 232: ...ppm MELF Resistor R 215 4 01167 462 3 32K Thin Film 1 50 ppm MELF Resistor R 216 4 01461 461 180 Thick Film 5 200 ppm Chip Resistor R 217 4 01167 462 3 32K Thin Film 1 50 ppm MELF Resistor R 218 4 011...

Page 233: ...64K Thin Film 1 50 ppm MELF Resistor R 371 4 01181 462 4 64K Thin Film 1 50 ppm MELF Resistor R 372 4 01150 462 2 21K Thin Film 1 50 ppm MELF Resistor R 373 4 01150 462 2 21K Thin Film 1 50 ppm MELF...

Page 234: ...st Jack Z 201 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 203 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 206 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 207 5 00315 5...

Page 235: ...Capacitor Ceramic SMT1206 50V 20 Z5U Z 342 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 343 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 349 5 00315 527 1UF Capacitor Ceramic SMT12...

Page 236: ...6 50V 5 NPO C 674 5 00387 552 1000P Capacitor Chip SMT1206 50V 5 NPO C 675 5 00387 552 1000P Capacitor Chip SMT1206 50V 5 NPO C 676 5 00387 552 1000P Capacitor Chip SMT1206 50V 5 NPO C 677 5 00387 552...

Page 237: ...62 2 21K Thin Film 1 50 ppm MELF Resistor R 604 4 01181 462 4 64K Thin Film 1 50 ppm MELF Resistor R 605 4 00978 462 35 7 Thin Film 1 50 ppm MELF Resistor R 606 4 00978 462 35 7 Thin Film 1 50 ppm MEL...

Page 238: ...687 4 01162 462 2 94K Thin Film 1 50 ppm MELF Resistor R 688 4 01162 462 2 94K Thin Film 1 50 ppm MELF Resistor R 689 4 01162 462 2 94K Thin Film 1 50 ppm MELF Resistor R 690 4 01162 462 2 94K Thin Fi...

Page 239: ...n Film 1 50 ppm MELF Resistor W 606 4 01024 462 107 Thin Film 1 50 ppm MELF Resistor W 607 4 01024 462 107 Thin Film 1 50 ppm MELF Resistor W 608 4 01024 462 107 Thin Film 1 50 ppm MELF Resistor W 609...

Page 240: ...1 00143 101 TEST JACK Vertical Test Jack Z 600 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 601 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 602 5 00315 527 1UF Capacitor Ceramic S...

Page 241: ...0V 20 Z5U Z 665 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 666 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 667 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 668 5 00315...

Page 242: ...ase sizes F 951 5 00471 569 10U T16 Cap Tantalum SMT all case sizes F 952 5 00471 569 10U T16 Cap Tantalum SMT all case sizes F 953 5 00471 569 10U T16 Cap Tantalum SMT all case sizes F 954 5 00471 56...

Page 243: ...50 ppm MELF Resistor R 931 4 01455 461 100 Thick Film 5 200 ppm Chip Resistor R 932 4 01175 462 4 02K Thin Film 1 50 ppm MELF Resistor R 933 4 01133 462 1 47K Thin Film 1 50 ppm MELF Resistor R 934 4...

Page 244: ...206 50V 20 Z5U Z 934 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 935 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 936 5 00315 527 1UF Capacitor Ceramic SMT1206 50V 20 Z5U Z 937 5...

Page 245: ...c Z 0 0 00180 000 LEFT FOOT Hardware Misc Z 0 0 00185 021 6 32X3 8PP Screw Panhead Phillips Z 0 0 00187 021 4 40X1 4PP Screw Panhead Phillips Z 0 0 00204 000 REAR FOOT Hardware Misc Z 0 0 00241 021 4...

Page 246: ...Parts Lists SR844 RF Lock In Amplifier 6 80 Schematic Diagrams...

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