Instruction/ maintenance manual of the product Lock-In Amplifier SRS Labs
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MODEL SR530 LOCK-IN AMPLIFIER 1290-D R eamwood Ave nue Sunnyvale, C A 9408 9 U.S.A. Phone: (4 08) 744-9 040 • Fax: (408) 74 4-9049 Email: info@th inkSRS.com • www.thinkSRS.com Copyright © 1997, 2 001 Stanford Res ear ch Systems, Inc. All Rights Rese rved R ev.
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i Table of Contents Condensed Information SAFET Y and Preparati on for us e 1 Symbols 2 Specific ations 3 Front Pane l Sum mary 5 Abridge d Command List 7 Status By te Def inition 8 Configurat ion S w.
ii Circuit D escription Introduct ion 34 Si gnal Am pli fie r 34 Current Ampli fier 34 Notch Filter s 34 Bandpass Filter 34 Reference Oscill ator 35 PSD, L P Filters an d DC Amp lifier 35 Analog O utp.
1 Safety and Preparation for Use ***CAUTION** * : This instrum ent may b e dama ged if oper ated with the LIN E VO LTAGE SELECTO R set for the wrong a pplie d ac inp ut-sourc e voltage or if th e wrong fus e is i nstalle d.
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3 SR530 Specificatio n Summary Genera l Power 100, 120, 22 0, 240 VAC (50/ 60 Hz); 3 5 Watts M ax Mechanic al 17" x 17 " x 5.25 " (Rac k Mount Inc luded) 16 lbs .
4 Acquis ition Time 25 Sec at 1 Hz 6 Sec at 1 0 Hz 2 Sec at 1 0 kHz Slew Rat e 1 decade per 10 S at 1 kH z Phase Contr ol 90° shifts Fine shifts in 0.
5 Front Panel Sum mary Signal In puts Single E nded (A), T rue Di fferential ( A-B), or Curr ent (I) Signal F ilters Bandpas s: Q-of-5 Aut o-track ing filter (In or O ut) Line Notch : Q-of-10 Notc h F.
6 Phase Contr ols Adjust phas e in smo othly accelera ting 0. 025° ste ps, or by 90° steps . Press b oth 90° buttons to zero th e phase. Reference LCD Display reference phase s etting or referenc e frequenc y Time Consta nts Pre-filter h as time c onstants fr om 1 mS to 100 S (6 dB /Octave) Post-filter has ti me constants of 0, 0.
7 Abridged Comma nd List AX Auto offset X AY Auto offset Y AR Auto offset R AP Auto ph ase B Return Ba ndpas s Filter Sta tus B0 Take out the Bandp as s Filter B1 Put in the Bandp ass Filter C Return .
8 Status Byte Definition Bit Meaning 0 Magnitude too small to calculate phase 1 Command Parameter is out-of-range 2 No detectable reference input 3 PLL is not locked to the reference 4 Signal Overload.
9 SR510 Guide to Operation Front Panel The front pa nel has been des ign ed to be al most self-expl anatory . The effec t of eac h keypres s is usually r eflected in the ch ange of a nearby LED indicator or by a c hange in the qu antity shown on a digital disp lay.
10 Dynamic R eserv e Sensitivity Rang e LOW 1 µ V through 5 00 mV NORM 100 nV t hrough 5 0 mV HIGH 100 nV thr ough 5 mV Dynamic Reserve The dyna mic reserv e (DR) is set usi ng the key s in the DYN AMI C RE S ERV E se ction. The reserve i s display ed by the three in dic at or LED's , HIGH , NORM , LOW .
11 display CH1 X setting output expand? offset? (RCOSØ ) X X+X ofst yes yes X+X ofst XOFST X ofst yes yes X ofst R R+R ofst yes yes X+X ofst R OFST R ofst yes yes X+X ofst XNOISE X noise yes yes X+X ofst (enbw) X5 X5 no adjust X+X ofst The EXPAND and OFFSET conditions for each display are retained when t he DISPLAY is changed.
12 to ON ) sets the offset to t he pr eviously entered value. If an attempt is m ade to adv ance the offset va lue beyond fu ll scal e, the ON LED will bl ink. An offset up to 1.024 t imes the full sc ale sens itivity may be entered. When the EXPAND is on , this is 10X t he full scale output.
13 possible. I f R is less than 0. 5% of fu ll sca le, the phase outp ut defa ults to zer o degrees . The Phase O utput may not b e expand ed and the OFFSET keys do not offs et the Phase Outp ut. However, the Phase Outp ut can be offset us ing the Referenc e Phas e shift.
14 down, the offs et adva nces in larger and lar ger increme nts, the lar gest inc rement b eing 10% o f full scale. When the of fset is t urned OFF the appli ed offset ret urns to zer o but the offset va lue is n ot lost. The n ext pres s of the u pper offs et key (ret urn to ON ) sets the offset to t he pr eviously entered value.
15 going tra nsitions of the refer ence i nput. Th is mode trig gers on a negat ive puls e train or on th e falling e dges o f a TTL ty pe pulse train (remember ing th at the inpu t is ac co upled).
16 should be allowed t o appr oach a s teady v alue before a rea ding is taken. For the 1 Hz EN BW, this time is on the order of 15 to 30 s econds ; for the 10 Hz E NBW, the output s tabiliz es muc h faster. Th e nois e outp ut will v ary slig htly si nce there wil l always be noise v ariati ons that are s low compared to the ban dwidth.
17 SR530 Guide to Operation Rear Panel AC Power The ac lin e voltage select or car d, line fuse, and line cor d rece ptacle are locat ed in t he fuse ho lder at the left s ide of th e rear pa nel.
18 the REF OUTPUT on the r ear pane l to the REF INPUT on t he front p anel. T he REF OUTPUT is a 1 Vrms si ne wave. T he SINE OUTPUT may be used as t he stimu lus to the ex perimen t. The SINE OUTPUT can be set to three amp lit udes, 1 V, 100 mV, and 10 mV (rms) using the amp li tud e switch.
19 SR530 Guide to Programming The SR53 0 Lock- in Am plifier is re motely programmab le via b oth RS2 32 and G PIB interfac es. It may b e used with labora tory computer s or simp ly with a termina l. All fr ont panel f eatures (ex cept s ignal in put selec tion and power) may be contr olled an d read via the computer interfac es.
20 The REM LED is on whe never th e SR530 is programmed to be in the rem ote state. RS232 Echo and No Echo Operation In order to a llow the SR530 to be oper ated from a terminal, an echo feature has been i ncluded which causes the unit to echo bac k commands rece ived over the R S232 por t.
21 SR530 Command Lis t The lead ing letter s in each comm and sequ ence specify the comm and. The r est of the s equenc e consists of parame ters. M ultip le param eters ar e separated by a comm a. Thos e parame ters shown in {} are optional whi le those wit hout {} are required.
22 23 200 mV 24 500 mV Note that se nsit ivity sett ings bel ow 100 n V are allowed on ly when a pre-am plifier is con nected. H The H comma nd reads the pre-a mplifier status . If a pre- amplifier is c onnected, a "1" is retur ned, otherwis e, a "0" is retur ned.
23 If n is inc luded, t hen v may be sent also. v is th e offset va lue up to plus or minus fu ll scal e in u nits of volts. For exam ple, to offs et ha lf of full s cale o n the 100 µ V s ensitiv ity, v s houl d be "50. 0E-6 " or an equivale nt va lue.
24 X n {,v} n designa tes one of the 6 ge neral pur pose analo g ports located on t he rear panel. If n is 1,2, 3, or 4, the X com mand wi ll return the volta ge on t he designate d analog input p ort (X1-X 4) in v olts. If n is 5 or 6 , then v m ay also be sent.
25 character s again. Reset The Z com mand res ets the u nit to its defau lt state. The defau lt front p anel sett ings are listed in the DEFAULTS sectio n of the Gu ide to O peration s .
26 6) Answers are co ming bac k from t he SR530 too slowly d ue to th e W6 d efault se tting for the charact er inter val tim e. Use the W command t o speed u p the trans miss ion from the S R530. Th is can ca use problems for the G PIB inter face if t he ec ho mode is o n (switc h 6 of S W1).
27 DC1 Devi ce Cle a r capa bilit y RL0 REN,L LO , GTL not imp lemen ted. 'I' command sets Remo te-Local. SR530 Resp onse to G PIB C ommands Mnemon ic Command Response DCL Device Clear Same .
28 The Lock-in Technique The Lock-in techniqu e is u sed to detect and measure very small ac signals. A Lock-in amplifier can make accurate measurements of small sig nal s even when the signals a re obscured by noise sources whic h may b e a thousand times larger.
29 Vpsd1 = V s cos(w r t) cos(w s t+ Ø ) = 1/2 V s cos[(w r + w s )t + Ø ] + 1/2 V s cos[(w r - w s )t+ Ø ] Vpsd2 = Vs sin(w r t) cos(w s t+ Ø ) = 1/2 V s sin[(w r + w s )t+ Ø ] + 1/2 V s sin[(w .
30 In the first method, the lock - in uses the A input in a 'quasi-d ifferential' mode. Her e, the lock-in d etects the signa l as the v oltage b etween t he cent er and outer con ductors of the A input.
31 attenuated by 6 d B/octave mor e. You may wish to use the ba ndpass filter an d selec t a low dynamic reserv e setting i n order to ac hieve a better o utput stability .
32 SR530 Block Diagram Severa l new concep ts are us ed to s implify the design of SR530 loc k -in amp lif ier. In additi on to implement ing recent adv anc es in li near int egr ate d circuit tec hnology , the ins trument w as desi gned to take full advantag e of its micropr ocess or contro ller to improve perform ance and t o reduc e cost.
33 The Signal Channel The instr ument has both cur rent and v oltage inputs. T he cur rent inp ut is a v irtual ground, a nd the 100 M Ω v oltage inputs c an be used as single- ended or tru e differe ntial inputs. There are three s ignal fi lters. Each of th ese filters may be sw itched 'in' or 'out' by th e user.
34 Circuit Description Introduction The SR53 0 Lock- in ampl ifier is an integr ated instrum ent combi ning stat e of the ar t analog design with advanc ed mic roproces sor base d contro l and interfac es. This discus sion is i ntende d to aid th e advanced user in ga ining a better unders tanding of the instrum ent.
35 U204, and U2 05 are analog s witches which s elect the feed back capac itors for the 5 decades of operation . The two halves of U202 are matc hed transconduc tance a mplif iers op erating as programmab le, volt age co ntrolled, c urrent so urces which tak e the plac e of the n ormal, freq uency setting, r esistors .
36 U419. Anal og switc h U418 se lects th e time co nstant and gain. T he full scale output of U4 18 is 5 volts. The quadrat ure d emodulator and low pass amplif iers are ident ical to t hat des cribe d above. Th e quadratur e detect or output is provi ded by U1119.
37 or, generates the gate puls e during which r eference pulses are count ed. I/O address es are dec oded by U705, U 706, an d U707. The micropr ocess or controls the lock-in functions thr ough I/O ports U 714-U721. U713 generates an inter rupt to t he CPU ev ery 4 msec to keep the m icroproc essor ex ecuting in re al time.
38 Calibration and Repair This section details calib ration of the instrument. Calibration should be done only by a qualified electronics technicia n. ********* WARNING ****** *** The calibration procedure requires adju sting the instrument with power applied and so there is a risk of personal injury or death by electric shock.
39 The CMRR is adjusted by the sin gle turn potentiometer located at A1 under the single hole at the front of the signal shield. (The shield is the aluminum box on the left side of the main board). Using a small screwdri ver, carefully adjust the potentiometer to minimize the 100 Hz output on the scope.
40 Appendi x A: Noise Sources a nd Cures Noise, rando m and uncor rel ated fl uc tuat ions of electron ic sig nals, fin ds its w ay int o exper iments in a var iety of ways .
41 Capacitive Co upling . A volta ge on a nearby piece of a pparatus (or op erator) can coup le to a detector vi a a stray c apacita nce. Although C stray may be very s mall, th e couple d in no ise may stil l be larger than a weak ex perime ntal signal.
42 Resistive Coupling (or 'Ground Loops') . Currents thr ough co mmon con nections can give rise to n oise vo ltages. Resistive C oupli ng Here, the d etector is meas uring th e volt age across the exper iment, plus the vo ltage d ue to the noise c urrent p assing t hrough th e finite resistanc e of the gr ound bus.
43 Appendi x B: Introductio n to the RS23 2 The 'RS232' is a st andard for bit ser ial asynchr onous data c ommunicat ion. Th e standard defines t he format for data transmiss ion, the e lectric al speci ficat ions for the signal lev els, and the mec ha nic a l dim ens io ns of connectors .
44 baud.) The typical data string 5.1 270<cr> has 7 characters, requiring 4 msec to be sent. Stop Bits Generally, selection of 2 stop bits will result in fewer data transmission errors. Parity The Parity bit provides a check against faulty data transfer.
45 Appendi x C: Introductio n to the GPIB The IEE E-488 St andard s pecifies t he vo ltage levels, handshak e requir ements , timing, hardware det ails, p inout a nd connec tor dimensio ns for a 16 line, bit para ll el bus. Many instrum ents may be c onnecte d in ser ies to communic ate over the same cable.
46 Appendi x D: Program Examples All of the progra m exampl es whic h follow d o the same thin g, only th e com puter, la nguage , or interfac e is cha nged. T he programs read t he Channel 1 a nd 2 Outp uts and wr ite th e results to the comput er sc reen.
47 Program Example 2: IBM PC, Microsoft Fortra n v3.3, via RS232 Machine language r outines to int erface to th e COM1: RS2 32 port ar e provid ed in t he file RS232.OBJ f ound o n the SR 575 disk . Thes e routines allow for simple i nterfac ing to t he SR530 at 19.
48 call rxstr(str2) [ convert string variable into real variable v1 and v2 read (str1,1000) v1 read (str2,1000) v2 1000 format (bn,f10.0) [ print results to screen write(*,2000) v1, v2 2000 format( ′ Channel 1 = ′ ,G 1 0.3,3x, ′ Channel 2= ′ ,G 1 0.
49 Program Example 3: IBM PC, Microsoft C v 3.0, via RS232 Machine language r outines to int erface to th e COM1: RS2 32 port ar e provid ed in t he file RS232.OBJ f ound o n the SR 575 disk . Thes e routines allow for simple i nterfac ing to t he SR530 at 19.
50 txstr ( ″ q2$ ″ ); /* read channel 2 output */ rxstr (str2); /* into str2 */ sscanf (str2, ″ %f ″ , &v2); /* scan str2 for a float variable */ x += 0.
51 Program Example 4: IBM PC,Microsoft Basic, via GPIB This progr am req uires t he Cap ital Equi pment Corporation GPIB c ard for the IBM PC or XT. It has firm ware in RO M to inter face h igh level languages to the G PIB. Subrouti ne calls in Mic rosoft BA SIC are d one to memory locations s pecifi ed by the name of the subroutine.
52 390 ′ 400 PRINT “CH1 = ″ ;V1; ″ CH2 = ″ ;V2 410 ′ 420 X = X + .0025 ′ INCREMENT X6 OUTPUT BY 2.5 MV 430 IF X>10 THEN X 0 ′ RESET RAMP 440 X$ = X6$ + STR$(X) + ″′ 1 3 ″′ M.
53 Program Example 5: HP85 via GPIB This progr am prov ides a n examp le of an HP85 progr am usin g the G PIB int erface wh ich co uld be used to control t he lock in ampl ifier. In this ex ample, the SR530 s hould be addr essed as device #16 by s etting the switch ba nk SW1 per the i nstruc tions Pa ge 7.
54 Documentation This section contains the parts lists an d schematics for the SR530 lock-in amplifi er. The first digit of any part number can b e use d to locate the schematic diagram for the part. For example, R415 is located on sh eet 4 of the schematic diagrams.
SR530 COMPONENT P ARTS LIST 55 Oscillator Bo ard Parts List REF. SRS part # VALUE DESCRIPTION C 1 5-00023-52 9 .1U Cap, Monolythic Ceramic , 50V, 20% , Z5U C 2 5-00023-52 9 .1U Cap, Monolythic Ceramic , 50V, 20% , Z5U C 3 5-00102-51 7 4.7U Capacitor, T antalum, 35V, 2 0%, Rad C 4 5-00054-51 2 .
SR530 COMPONENT P ARTS LIST 56 Main Board Part s List REF. SRS part # VALUE DESCRIPTION BR1 3-00062- 340 KBP20 1G/BR-81D Integrated Circuit ( Thru-ho le Pkg) BR2 3-00062- 340 KBP20 1G/BR-81D Integrated Circuit ( Thru-ho le Pkg) BT1 6- 00001-61 2 BR- 2/3A 2PIN PC Batt ery C 101 5- 00069-51 3 .
SR530 COMPONENT P ARTS LIST 57 REF. SRS part # VALUE DESCRIPTION C 214 5- 00059-51 2 .47U Cap, Stack ed Meta l Film 5 0V 5% -40/ +85c C 215 5- 00060-51 2 1.
SR530 COMPONENT P ARTS LIST 58 REF. SRS part # VALUE DESCRIPTION C 410 5- 00056-51 2 .1U Cap, Stac ked Met al Film 5 0V 5% - 40/+85c C 411 5- 00056-51 2 .1U Cap, Stac ked Met al Film 5 0V 5% - 40/+85c C 412 5- 00056-51 2 .1U Cap, Stac ked Met al Film 5 0V 5% - 40/+85c C 413 5- 00049-56 6 .
SR530 COMPONENT P ARTS LIST 59 REF. SRS part # VALUE DESCRIPTION C 802 5- 00012-50 1 330P Capaci tor, Ceramic Disc , 50V, 10%, SL C 803 5- 00012-50 1 330P Capaci tor, Ceramic Disc , 50V, 10%, SL C 804 5- 00052-51 2 .01U Cap, Stack ed Meta l Film 5 0V 5% -40/ +85c C 805 5- 00052-51 2 .
SR530 COMPONENT P ARTS LIST 60 REF. SRS part # VALUE DESCRIPTION CY1 6-00010- 620 4.000 MHZ Crystal D 101 3- 00004-30 1 1N41 48 Diode D 102 3- 00004-30 1 1N41 48 Diode D 103 3- 00004-30 1 1N41 48 Diod.
SR530 COMPONENT P ARTS LIST 61 REF. SRS part # VALUE DESCRIPTION R 102 4- 00033-40 4 100M Resistor, Car bon Com p, 1/4W, 5% R 103 4- 00030-40 1 10 Resistor, Car bon F ilm, 1/4W, 5% R 104 4- 00031-40 1 100 Resistor , Carbon F ilm, 1/4W , 5% R 105 4- 00031-40 1 100 Resistor , Carbon F ilm, 1/4W , 5% R 108 4- 00130-40 7 1.
SR530 COMPONENT P ARTS LIST 62 REF. SRS part # VALUE DESCRIPTION R 162 4- 00188-40 7 4.99K Resistor, Meta l Film, 1/8W, 1 %, 50PPM R 163 4- 00035-40 1 10M Resistor , Carbon F ilm, 1/4W , 5% R 165 4- 0.
SR530 COMPONENT P ARTS LIST 63 REF. SRS part # VALUE DESCRIPTION R 307 4- 00040-40 1 13K Resis tor, Carbon F ilm, 1 /4W, 5% R 308 4- 00193-40 7 499 Resistor, Meta l Film, 1/8W, 1%, 5 0PPM R 309 4- 00073-40 1 330K Resis tor, Carbon F ilm, 1 /4W, 5% R 310 4- 00021-40 1 1.
SR530 COMPONENT P ARTS LIST 64 REF. SRS part # VALUE DESCRIPTION R 359 4- 00045-40 1 2.0K R esistor, Car bon F ilm, 1/4W, 5% R 360 4- 00032-40 1 100K Resis tor, Carbon F ilm, 1 /4W, 5% R 361 4- 00084-40 1 5.1K R esistor, Car bon F ilm, 1/4W, 5% R 362 4- 00181-40 7 32.
SR530 COMPONENT P ARTS LIST 65 REF. SRS part # VALUE DESCRIPTION R 433 4- 00021-40 1 1.0K R esistor, Car bon F ilm, 1/4W, 5% R 501 4- 00022-40 1 1.0M Resis tor, Carbon F ilm, 1 /4W, 5% R 502 4- 00022-40 1 1.0M Resis tor, Carbon F ilm, 1 /4W, 5% R 503 4- 00022-40 1 1.
SR530 COMPONENT P ARTS LIST 66 REF. SRS part # VALUE DESCRIPTION R 703 4- 00027-40 1 1.5K R esistor, Car bon F ilm, 1/4W, 5% R 705 4- 00021-40 1 1.0K R esistor, Car bon F ilm, 1/4W, 5% R 706 4- 00034-.
SR530 COMPONENT P ARTS LIST 67 REF. SRS part # VALUE DESCRIPTION U 118 3- 00130-34 0 5532A Integrated Cir cuit (T hru-hole Pk g) U 201 3- 00087-34 0 LF347 Integrated Circuit ( Thru-ho le Pkg) U 202 3-.
SR530 COMPONENT P ARTS LIST 68 REF. SRS part # VALUE DESCRIPTION U 415 3- 00126-33 5 51A05 Relay U 416 3- 00084-34 0 ICL7650 Integrated Circ uit (Thru- hole Pk g) U 417 3- 00126-33 5 51A05 Relay U 418.
SR530 COMPONENT P ARTS LIST 69 REF. SRS part # VALUE DESCRIPTION U 807 3- 00110-34 0 MC1489 Integrated Circ uit (Thru- hole Pk g) U 808 3- 00078-34 0 DS75160 A Integrated Circui t (Thru- hole Pk g) U .
SR530 COMPONENT P ARTS LIST 70 REF. SRS part # VALUE DESCRIPTION Z 0 0-0025 7-00 0 HANDL E3 Hardware, Misc . Z 0 0- 00371-02 6 4-40X3/1 6PF Scr ew, Black, All Ty pes Z 0 0- 00500-00 0 5548 08-1 Hardware, Misc.
SR530 COMPONENT P ARTS LIST 71 REF. SRS part # VALUE DESCRIPTION DS611 3-00012-30 6 G REEN LED, Rec tan gu lar DS612 3-00012-30 6 G REEN LED, Rec tan gu lar DS613 3-00012-30 6 G REEN LED, Rec tan gu l.
SR530 COMPONENT P ARTS LIST 72 REF. SRS part # VALUE DESCRIPTION DS662 3-00012-30 6 G REEN LED, Rec tan gu lar DS663 3-00012-30 6 G REEN LED, Rec tan gu lar DS664 3-00012-30 6 G REEN LED, Rec tan gu l.
SR530 COMPONENT P ARTS LIST 73 REF. SRS part # VALUE DESCRIPTION RN603 4-00226-42 5 150X9 Resistor Net work SI P 1/4W 2% ( Common) RN604 4-00222-42 5 150X7 Resistor Net work SI P 1/4W 2% ( Common) U 6.
SR530 COMPONENT P ARTS LIST 74 REF. SRS part # VALUE DESCRIPTION C 1006 5-0005 8-51 2 .33U Cap, Stacked Metal F ilm 50V 5% -40/ +85c C 1007 5-0004 9-566 .
SR530 COMPONENT P ARTS LIST 75 REF. SRS part # VALUE DESCRIPTION P 1103 4-00016- 445 10K Pot, Multi- Turn , Side A djust P 1104 4-00016- 445 10K Pot, Multi- Turn , Side A djust P 1201 4-00016- 445 10K.
SR530 COMPONENT P ARTS LIST 76 REF. SRS part # VALUE DESCRIPTION R 1109 4-0002 2-401 1.0M Resistor, Carbon F ilm, 1/ 4W, 5% R 1110 4-0021 7-40 8 1.00 0K Resistor , Metal F ilm, 1/8 W, 0.1%, 25ppm R 1111 4-0019 3-407 499 Resistor , Metal F ilm, 1/8 W, 1%, 5 0PPM R 1112 4-0021 7-40 8 1.
SR530 COMPONENT P ARTS LIST 77 REF. SRS part # VALUE DESCRIPTION U 1102 3-0009 1-34 0 LF 412 Integrated Circ uit (Thr u-hole Pk g) U 1103 3-0009 0-34 0 LF 411 Integrated Circ uit (Thr u-hole Pk g) U 1.
SR530 COMPONENT P ARTS LIST 78.
An important point after buying a device SRS Labs Lock-In Amplifier (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought SRS Labs Lock-In Amplifier yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data SRS Labs Lock-In Amplifier - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, SRS Labs Lock-In Amplifier you will learn all the available features of the product, as well as information on its operation. The information that you get SRS Labs Lock-In Amplifier will certainly help you make a decision on the purchase.
If you already are a holder of SRS Labs Lock-In Amplifier, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime SRS Labs Lock-In Amplifier.
However, one of the most important roles played by the user manual is to help in solving problems with SRS Labs Lock-In Amplifier. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device SRS Labs Lock-In Amplifier along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center